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Aurora

Serge — Fri, 18 Dec 2009 05:57:37 GMT

For those in the high Northern Hemisphere, (and not only):

...

"The Sun produced a number of flares yesterday (Wednesday), and at least one Earth-directed coronal mass ejection was observed. It is possible that we will see some Northern Lights later tonight, although I'd say tomorrow night (Friday night) is more likely. With the new moon, the skies are good and dark too. So keep looking up, and call everyone you know if you spot some aurorae!"

...

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As the World Churns

Serge — Wed, 23 Dec 2009 03:55:45 GMT

Feature, Dec. 22, 2009

The full version of this story with accompanying images is at: http://www.jpl.nasa.gov/news/features.cfm?feature=2420

Story Highlights:

Study confirms theories that Earth's liquid outer core is slowly "stirred" in a series of regularly occurring waves of motion that last for decades.
Measurements of Earth's magnetic field from observatory stations on land and ships at sea were combined with satellite data to determine common patterns of movement within Earth's core.
The findings give scientists new insights into Earth's internal structure, the mechanisms that generate its magnetic field, and its geology.
Earth's magnetic field shields us from harmful solar radiation and has many practical applications, ranging from navigation to archaeology.

"Terra firma." It's Latin for "solid Earth." Most of the time, at least from our perspective here on the ground, Earth seems to be just that: solid. Yet the Earth beneath our feet is actually in constant motion. It moves through time and space, of course, along with the other objects in the universe, but it moves internally as well. The powerful forces of wind, water and ice constantly erode its surface, redistributing Earth's mass in the process. Within Earth's solid crust, faulting literally creates and then moves mountains. Hydrological changes, such as the pumping of groundwater for use by humans, cause the ground beneath us to undulate. Volcanic processes deform our planet and create new land. Landslides morph and scar the terrain. Entire continents can even rise up, rebounding from the weight of massive glaciers that blanketed the land thousands of years ago.

Indeed, the outermost layers of the celestial blue onion that is Earth-its crust and upper mantle-aren't very solid at all. But what happens if we peel back the layers and examine what's going on deep within Earth, at its very core?

Obviously, Earth's core is too deep for humans to observe directly. But scientists can use indirect methods to deduce what's going on down there. A new study in the journal Geophysical Research Letters, by Jean Dickey of NASA's Jet Propulsion Laboratory, Pasadena, Calif. and co-author Olivier deViron of the Institut de Physique du Globe de Paris, University Paris Diderot, Centre National de la Recherche Scientifique, Paris, has confirmed previous theoretical predictions that the churning cauldron of molten metals that make up Earth's liquid outer core is slowly being stirred by a very complex but predictable series of periodic oscillations. The findings give scientists unique insights into Earth's internal structure, the strength of the mechanisms responsible for generating Earth's magnetic field and its geology.

Peeling Back the Onion

In order to better understand what's going on inside our planet, it helps to first get a lay of the land, so to speak.

Earth has several distinct layers, each with its own properties. At the outermost layer of our planet is the crust, which comprises the continents and ocean basins. Earth's crust varies in thickness from 35 to 70 kilometers (22 to 44 miles) in the continents and 5 to 10 kilometers (3 to 6 miles) in the ocean basins. The crust is mainly composed of alumino-silicates.

Next comes the mantle. The mantle is roughly solid, though very slow motion can be observed inside of it. It is about 2,900 kilometers (1,800 miles) thick, and is separated into an upper and lower mantle. It is here where most of Earth's internal heat is located. Large convective cells in the mantle circulate heat and drive the movements of Earth's tectonic plates, upon which our continents ride. The mantle is mainly composed of ferro-magnesium silicates.

Earth's innermost layer is the core, which is separated into a liquid outer core and a solid inner core. The outer core is 2,300 kilometers (1,429 miles) thick, while the inner core is 1,200 kilometers (746 miles) thick. The outer core is mainly composed of a nickel-iron alloy (liquid iron), while the inner core is almost entirely composed of a pure solid iron body.

Earth's "Magnetic" Personality

Scientists believe Earth's magnetic field results from movements of molten iron and nickel within its liquid outer core. These flows, which are caused by interactions between Earth's core and its mantle, are neither even, nor evenly distributed. The electrical currents generated by these flows result in a magnetic field, which is similarly uneven, moves around in location and varies in strength over time. Earth's magnetic field is also slightly tilted with respect to Earth's axis. This causes Earth's geographic north and south poles to not line up with its magnetic north and south poles--they currently differ by about 11 degrees.

In just the last 200 million years alone, Earth's magnetic poles have actually reversed hundreds of times, with the most recent reversal taking place about 790,000 years ago. Scientists are able to reconstruct the chronology of these magnetic pole reversals by studying data on the spreading of the seafloor at Earth's mid-oceanic ridges. Unlike the doomsday scenario popularized by Hollywood in the movie "2012," however, such reversals don't occur over days, but rather on geologic timescales spanning hundreds to thousands of years-very short in geologic time but comparatively long in human time. The time span between pole reversals is even longer, ranging from 100,000 to several million years.

Earth's magnetic field is essential for life on Earth. Extending thousands of kilometers into space, it serves as a shield, deflecting the constant bombardment of charged particles and radiation known as the solar wind away from Earth. These solar winds would otherwise be fatal to life on Earth. At Earth's poles, the perpendicular angle of the magnetic field to Earth there allows some of these particles to make it into our atmosphere. This results in the Northern Lights in the northern hemisphere and the Southern Lights in the southern hemisphere.

Here on the ground, Earth's magnetic field has many practical applications to our everyday lives. It allows people to successfully navigate on land and at sea, making it a critical tool for commerce. Hikers use it to find their way. Archaeologists use it to deduce the age of ancient artifacts such as pottery, which, when fired, assumes the magnetic field properties that were present at the time of its creation. Similarly, the field of paleomagnetism uses magnetism to give scientists glimpses into Earth's remote past. In addition, geophysicists and geologists use geomagnetism as a tool to investigate Earth's structure and changes taking place in the Earth.

Getting to the Core of the Matter

Since Earth's liquid core is the primary source of Earth's magnetic field, scientists can use observations of the magnetic field at Earth's surface and its variability over time to mathematically calculate and isolate the approximate motions taking place within the core.

That's what Dickey and deViron did. They combined measurements of Earth's magnetic field taken by observatory stations on land and ships at sea dating back to 1840 with those of the Danish Oersted and German CHAMP geomagnetic satellite missions, both of which were supported by NASA investments. These measurements were then used as inputs for a complex model that employs statistical time series analyses to determine how fast liquid iron is flowing within Earth's core.

"Although we do not observe the core directly, it's amazing how much we can learn about Earth's interior using magnetic field observations," said Dickey.

In order to approximate the flow of liquid in the core, the scientists visualized its motion as a set of 20 rigid cylinders, each rotating about a common point that represents Earth's axis. "Imagine that each cylinder is slowly rotating at a different speed, and you'll get a sense of the complex churning that's taking place within Earth's core," Dickey said.

The scientists analyzed the data to identify common patterns of movement among the different cylinders. These patterns represent how momentum and energy are transferred from the liquid core-mantle interface inward through the liquid core toward the inner core with diminishing amplitudes.

Their analyses isolated six slow-moving oscillations, or waves of motion, occurring within the liquid core. The oscillations originated at the boundary between Earth's core and its mantle and traveled inward toward the inner core with decreasing strength. Four of these oscillations were robust, occurring at periods of 85, 50, 35 and 28 years. Since the scientist's data set goes back to 1840, the recurrence period of the longest oscillation (85 years) is less well determined than the other oscillations. The last two oscillations identified were weaker and will require further study.

The 85- and 50-year oscillations are consistent with a 1997 study by researchers Stephen Zatman and Jeremy Bloxham of Harvard University, Cambridge, Mass., who used a different analysis technique. A later purely theoretical study by Harvard researcher Jon Mound and Bruce Buffett of the University of Chicago in 2006 showed that there should be several oscillations of this type; their predicted periods agree with the first four modes identified in Dickey and deViron's study.

"Our satellite-based results are in excellent agreement with the previous theoretical and other studies in this field, providing a strong confirmation of the existence of these oscillations," said Dickey. "These results will give scientists confidence in using satellite measurements in the future to deduce long-term changes taking place deep within our restless planet."results are in excellent agreement with the previous theoretical and other studies in this field, providing a strong confirmation of the existence of these oscillations," said Dickey. "These results will give scientists confidence in using satellite measurements in the future to deduce long-term changes taking place deep within our restless planet."

Media Contact:

Alan Buis 818-354-0474
Jet Propulsion Laboratory, Pasadena, Calif.
Alan.buis@jpl.nasa.gov

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"JPL on the Go!"

Serge — Wed, 23 Dec 2009 03:58:37 GMT

"JPL on the Go!": From Earth to Space in a Matter of Seconds

The next time Spirit moves an inch or scientists find a new ring on Saturn, don't be the last one to know. A newly enhanced, mobile-friendly Web site from NASA's Jet Propulsion Laboratory makes it easier for you to discover what's happening across the solar system and beyond no matter where you are.

"JPL on the Go!" takes all your favorite content from our standard Web site (news, videos and educational activities) and formats it for friendly browsing using your smartphone -- no zooming in, moving around pages or lengthy scrolling required. Even users of non-smartphone mobiles can get in on the action with our text-based site, which offers streamlined text-only news and feature content.

Getting there is as simple as typing in our standard URL, jpl.nasa.gov, into your phone's browser. You'll automatically be connected to the specially optimized site so you can start reading stories or watching videos in a matter of seconds. Bookmark the site, and you'll get there even faster the next time.

Visit www.jpl.nasa.gov/onthego/ to learn more about JPL's mobile initiatives and how you can optimize your mobile experience.

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Eyes in the Sky II Seeks Grade 9 to 12 Science Teachers

Serge — Wed, 23 Dec 2009 03:53:00 GMT

Eyes in the Sky II is a long-term professional development program that prepares high school science teachers to use NASA data and visualizations along with other geospatial information technologies. Throughout the program, teachers and students investigate both global and local environmental issues. The program includes four parts:

1) A 12-week online Web course, consisting of three 4-week modules
2) A 7-day face-to-face summer workshop held onsite at a NASA research center
3) One year of classroom implementation, ending with a virtual student showcase
4) An ambassador program for providing professional development for other teachers in participants' schools or districts.

Grade 9 to 12 science teachers will benefit from this program. Through participating, teachers will:

1) Become proficient using NASA data and geospatial analysis tools
2) Receive a $1000 stipend for completing the online course and the 7-day summer workshop
3) Receive an additional $1000 stipend as compensation for delivering professional development as an Eyes in the Sky II Ambassador
4) Equip their students with geospatial technology skills that are in increasing demand in the workplace
5) Obtain optional graduate credit through Northern Arizona University.

For more information about the Eyes in the Sky II program, including the online application visit http://serc.carleton.edu/eyesinthesky2/index.html . Applications are due by January 15, 2010. We expect this will be a popular program. As there are a limited number of openings available, first consideration will be given to early applicants. If you have further questions, please contact Carla McAuliffe ( Carla_McAuliffe@terc.edu ) or Erin Bardar ( Erin_Bardar@terc.edu ).

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East Coast Blizzard 2009

idea1407 — Mon, 21 Dec 2009 23:48:56 GMT

http://www.wired.com/wiredscience/2009/12/east-coast-blizzard-from-space?npu=1&mbid=yhp

>"East Coast Blizzard Seen From Space

The snowstorm that blanketed the East Coast this weekend was so big, it is even impressive from space. NASA’s Aqua satellite took this image centered on Washington, D.C., on Sunday with its MODIS instrument.

The blizzard shut down the federal government, stranded travelers, left hundreds of thousands without power and crushed the hopes of many retailers hoping for big sales during the weekend before Christmas.

The image covers 300 miles lengthwise. The two big rivers near the center are the Susquehanna (to the north) and Potomac rivers, which run into Chesapeake Bay. Washington, D.C., sits alongside the Potomac, just north of the river’s hook-shaped curve. The inlet to the north is Delaware Bay."<

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Glint of Sunlight Confirms Liquid in Northern Lake District of Titan

Serge — Fri, 18 Dec 2009 23:49:51 GMT

Jia-Rui C. Cook 818-354-0850
Jet Propulsion Laboratory, Pasadena, Calif.
jia-rui.c.cook@jpl.nasa.gov

Image advisory: 2009-199 Dec. 17, 2009

The full version of this story with accompanying images is at: http://www.jpl.nasa.gov/news/news.cfm?release=2009-199&cid=kintera_advisory_2009-199

PASADENA, Calif. -- NASA's Cassini Spacecraft has captured the first flash of sunlight reflected off a lake on Saturn's moon Titan, confirming the presence of liquid on the part of the moon dotted with many large, lake-shaped basins.

Cassini scientists had been looking for the glint, also known as a specular reflection, since the spacecraft began orbiting Saturn in 2004. But Saturn's northern hemisphere, which has more lakes than the southern hemisphere, has been veiled in winter darkness. The sun only began to directly illuminate the northern lakes recently as it approached the equinox of August 2008, the start of spring in the northern hemisphere. Titan's hazy atmosphere also blocked out reflections of sunlight in most wavelengths. This serendipitous image was captured on July 8, 2009, using Cassini's visual and infrared mapping spectrometer.

The new infrared image is available online at: http://www.nasa.gov/cassini , http://saturn.jpl.nasa.gov and http://wwwvims.lpl.arizona.edu .

This image will be presented Friday, Dec. 18, at the fall meeting of the American Geophysical Union in San Francisco.

"This one image communicates so much about Titan -- thick atmosphere, surface lakes and an otherworldliness," said Bob Pappalardo, Cassini project scientist, based at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "It's an unsettling combination of strangeness yet similarity to Earth. This picture is one of Cassini's iconic images."

Titan, Saturn's largest moon, has captivated scientists because of its many similarities to Earth. Scientists have theorized for 20 years that Titan's cold surface hosts seas or lakes of liquid hydrocarbons, making it the only other planetary body besides Earth believed to harbor liquid on its surface. While data from Cassini have not indicated any vast seas, they have revealed large lakes near Titan's north and south poles.

In 2008, Cassini scientists using infrared data confirmed the presence of liquid in Ontario Lacus, the largest lake in Titan's southern hemisphere. But they were still looking for the smoking gun to confirm liquid in the northern hemisphere, where lakes are also larger.

Katrin Stephan, of the German Aerospace Center (DLR) in Berlin, an associate member of the Cassini visual and infrared mapping spectrometer team, was processing the initial image and was the first to see the glint on July 10th.

"I was instantly excited because the glint reminded me of an image of our own planet taken from orbit around Earth, showing a reflection of sunlight on an ocean," Stephan said. "But we also had to do more work to make sure the glint we were seeing wasn't lightning or an erupting volcano."

Team members at the University of Arizona, Tucson, processed the image further, and scientists were able to compare the new image to radar and near-infrared-light images acquired from 2006 to 2008.

They were able to correlate the reflection to the southern shoreline of a lake called Kraken Mare. The sprawling Kraken Mare covers about 400,000 square kilometers (150,000 square miles), an area larger than the Caspian Sea, the largest lake on Earth. It is located around 71 degrees north latitude and 337 degrees west latitude.

The finding shows that the shoreline of Kraken Mare has been stable over the last three years and that Titan has an ongoing hydrological cycle that brings liquids to the surface, said Ralf Jaumann, a visual and infrared mapping spectrometer team member who leads the scientists at the DLR who work on Cassini. Of course, in this case, the liquid in the hydrological cycle is methane rather than water, as it is on Earth.

"These results remind us how unique Titan is in the solar system," Jaumann said. "But they also show us that liquid has a universal power to shape geological surfaces in the same way, no matter what the liquid is."

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The visual and infrared mapping spectrometer team is based at the University of Arizona, Tucson.

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The Virtual Planet Lab...

Frozenstars — Thu, 17 Dec 2009 18:07:15 GMT

See so yourself...

http://vpl.astro.washington.edu/

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Hubble Finds Smallest Kuiper Belt Object Ever Seen

idea1407 — Wed, 16 Dec 2009 21:53:20 GMT

http://hubblesite.org/newscenter/archive/releases/2009/33/full/

>"NASA's Hubble Space Telescope has discovered the smallest object ever seen in visible light in the Kuiper Belt, a vast ring of icy debris that is encircling the outer rim of the solar system just beyond Neptune.

The needle-in-a-haystack object found by Hubble is only 3,200 feet across and a whopping 4.2 billion miles away. The smallest Kuiper Belt Object (KBO) seen previously in reflected light is roughly 30 miles across, or 50 times larger.

This is the first observational evidence for a population of comet-sized bodies in the Kuiper Belt that are being ground down through collisions. The Kuiper Belt is therefore collisionally evolving, meaning that the region's icy content has been modified over the past 4.5 billion years.

The object detected by Hubble is so faint — at 35th magnitude — it is 100 times dimmer than what Hubble can see directly.

So then how did the space telescope uncover such a small body?

In a paper published in the December 17th issue of the journal Nature, Hilke Schlichting of the California Institute of Technology in Pasadena, Calif., and her collaborators are reporting that the telltale signature of the small vagabond was extracted from Hubble's pointing data, not by direct imaging.

Hubble has three optical instruments called Fine Guidance Sensors (FGS). The FGSs provide high-precision navigational information to the space observatory's attitude control systems by looking at select guide stars for pointing. The sensors exploit the wavelike nature of light to make precise measurement of the location of stars.

Schlichting and her co-investigators determined that the FGS instruments are so good that they can see the effects of a small object passing in front of a star. This would cause a brief occultation and diffraction signature in the FGS data as the light from the background guide star was bent around the intervening foreground KBO.

They selected 4.5 years of FGS observations for analysis. Hubble spent a total of 12,000 hours during this period looking along a strip of sky within 20 degrees of the solar system's ecliptic plane, where the majority of KBOs should dwell. The team analyzed the FGS observations of 50,000 guide stars in total.

Scouring the huge database, Schlichting and her team found a single 0.3-second-long occultation event. This was only possible because the FGS instruments sample changes in starlight 40 times a second. The duration of the occultation was short largely because of the Earth's orbital motion around the Sun.

They assumed the KBO was in a circular orbit and inclined 14 degrees to the ecliptic. The KBO's distance was estimated from the duration of the occultation, and the amount of dimming was used to calculate the size of the object. "I was very thrilled to find this in the data," says Schlichting.

Hubble observations of nearby stars show that a number of them have Kuiper Belt–like disks of icy debris encircling them. These disks are the remnants of planetary formation. The prediction is that over billions of years the debris should collide, grinding the KBO-type objects down to ever smaller pieces that were not part of the original Kuiper Belt population.

The finding is a powerful illustration of the capability of archived Hubble data to produce important new discoveries. In an effort to uncover additional small KBOs, the team plans to analyze the remaining FGS data for nearly the full duration of Hubble operations since its launch in 1990."<

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Water Found on Earth-Like Planet?

Hummingbird — Wed, 16 Dec 2009 22:18:46 GMT

http://cosmiclog.msnbc.msn.com/archive/2009/12/16/2152989.aspx

"Astronomers say they have detected a planet just six and a half times as massive as Earth - at a distance so close its atmosphere could be studied, and with a density so low it's almost certain to have abundant water."

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NASA's WISE Eye on the Universe Begins All-Sky Survey Mission

Serge — Mon, 14 Dec 2009 19:50:57 GMT

Whitney Clavin 818-354-4673/818-354-5011
Jet Propulsion Laboratory, Pasadena, Calif.
whitney.clavin@jpl.nasa.gov

J.D. Harrington 202-358-5241
NASA Headquarters, Washington
j.d.harrington@nasa.gov

News release: 2009-193 Dec. 14, 2009

The full version of this story with accompanying images is at: http://www.jpl.nasa.gov/news/news.cfm?release=2009-193&cid=kintera_release_2009-193

VANDENBERG AIR FORCE BASE, Calif. -- NASA's Wide-field Infrared Survey Explorer, or WISE, lifted off over the Pacific Ocean this morning on its way to map the entire sky in infrared light.

A Delta II rocket carrying the spacecraft launched at 6:09 a.m. PST (9:09 a.m. EST) from Vandenberg Air Force Base in California. The rocket deposited WISE into a polar orbit 326 miles above Earth.

"WISE thundered overhead, lighting up the pre-dawn skies," said William Irace, the mission's project manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "All systems are looking good, and we are on our way to seeing the entire infrared sky better than ever before."

Engineers acquired a signal from the spacecraft via NASA's Tracking and Data Relay Satellite System just 10 seconds after the spacecraft separated from the rocket. Approximately three minutes later, WISE re-oriented itself with its solar panels facing the sun to generate its own power. The next major event occurred about 17 minutes later. Valves on the cryostat, a chamber of super-cold hydrogen ice that cools the WISE instrument, opened. Because the instrument sees the infrared, or heat, signatures of objects, it must be kept at chilly temperatures. Its coldest detectors are less than minus 447 degrees Fahrenheit.

"WISE needs to be colder than the objects it's observing," said Ned Wright of UCLA, the mission's principal investigator. "Now we're ready to see the infrared glow from hundreds of thousands of asteroids, and hundreds of millions of stars and galaxies."

With the spacecraft stable, cold and communicating with mission controllers at JPL, a month-long checkout and calibration is underway.

WISE will see the infrared colors of the whole sky with sensitivity and resolution far better than the last infrared sky survey, performed 26 years ago. The space telescope will spend nine months scanning the sky once, then one-half the sky a second time. The primary mission will end when WISE's frozen hydrogen runs out, about 10 months after launch.

Just about everything in the universe glows in infrared, which means the mission will catalog a variety of astronomical targets. Near-Earth asteroids, stars, planet-forming disks and distant galaxies all will be easy for the mission to see. Hundreds of millions of objects will populate the WISE atlas, providing astronomers and other space missions, such as NASA's planned James Webb Space Telescope, with a long-lasting infrared roadmap.

JPL manages the Wide-field Infrared Survey Explorer for NASA's Science Mission Directorate in Washington. The mission was competitively selected under the Explorers Program, managed by NASA's Goddard Space Flight Center in Greenbelt, Md. The science instrument was built by the Space Dynamics Laboratory in Logan, Utah, and the spacecraft was built by Ball Aerospace & Technologies Corp. in Boulder, Colo. Science operations and data processing take place at the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena. NASA's Launch Services Program at NASA's Kennedy Space Center, Fla., managed the payload integration and the launch service.

More information about the WISE mission is available online at: http://www.nasa.gov/wise , http://wise.astro.ucla.edu and http://www.jpl.nasa.gov/wise .

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Vista telescope comes online

idea1407 — Sun, 13 Dec 2009 20:34:01 GMT

http://www.space.com/scienceastronomy/091211-vista-images.html

>"First Photos by VISTA Telescope Are Stunning
By SPACE.com Staff

posted: 11 December 2009
04:51 pm ET

When a new telescope comes online, astronomers are excited to see the first images. In the case of the VISTA observatory, they have every right to be excited.

The first images from VISTA (the Visible and Infrared Survey Telescope for Astronomy) rival the most striking photos of the cosmos taken from any observatory. A new view of the Flame Nebula is the most stunning, and a detailed look at stars and dust toward the middle of the Milky Way ain't half bad, either.

The new telescope is part of the European Southern Observatory's Paranal Observatory in the Atacama Desert of northern Chile.

"VISTA is a unique addition to ESO's observatory on Cerro Paranal. It will play a pioneering role in surveying the southern sky at infrared wavelengths and will find many interesting targets for further study by the Very Large Telescope, ALMA and the future European Extremely Large Telescope," said Tim de Zeeuw, the ESO Director General.

At the heart of VISTA is a 3-ton camera containing 16 special detectors sensitive to infrared light, with a combined total of 67 million pixels, ESO officials explained in a statement Friday. Observing at wavelengths longer than those visible with the human eye allows VISTA to study objects that are otherwise impossible to see in visible light because they are either too cool, obscured by dust clouds or because they are so far away that their light has been stretched beyond the visible range by the expansion of the universe.

Because VISTA is a large telescope that also has a large field of view it can both detect faint sources and also cover wide areas of sky quickly.

Each VISTA image captures a section of sky covering about ten times the area of the full moon and it will be able to detect and catalogue objects over the whole southern sky with a sensitivity that is 40 times greater than that achieved with earlier infrared sky surveys. This is comparable to the step in sensitivity from the unaided eye to Galileo's first telescope, officials said, and VISTA is expected to "reveal vast numbers of new objects and allow the creation of far more complete inventories of rare and exotic objects in the southern sky."
"<

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Gaia to be launched - another toy this Christmas

idea1407 — Wed, 16 Dec 2009 20:46:49 GMT

http://www.esa.int/esaCP/SEMOVL9K73G_index_0.html

>"Gaia to lift off from Europe’s Spaceport on a Soyuz launcher

16 December 2009
Gaia, ESA’s next-generation star mapper, will be carried into space by a Soyuz-STB/Fregat launch vehicle from Europe’s Spaceport in French Guiana. David Southwood, ESA’s Director of Science and Robotic Exploration, signed the contract for the launch with Jean-Yves LeGall, Chairman and CEO of Arianespace, at ESA Headquarters in Paris yesterday.

The mission builds upon the heritage of precision stellar mapping exemplified by ESA's now- completed Hipparcos mission. Gaia will map 1000 million stars at unprecedented levels of precision, with the objective to use its census of stars to clarify the history and origins of our Galaxy. "<

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NASA Data Reveal Major Groundwater Loss in California's Heartland

Serge — Mon, 14 Dec 2009 19:52:24 GMT

Alan Buis 818-354-0474
Jet Propulsion Laboratory, Pasadena, Calif.
Alan.buis@jpl.nasa.gov

News release: 2009-194 Dec. 14, 2009

The full version of this story with accompanying images is at: http://www.jpl.nasa.gov/news/news.cfm?release=2009-194&cid=kintera_release_2009-194

PASADENA, Calif. - New space observations reveal that since October 2003, the aquifers for California's primary agricultural region -- the Central Valley -- and its major mountain water source -- the Sierra Nevadas -- have lost nearly enough water combined to fill Lake Mead, America's largest reservoir. The findings, based on data from the NASA/German Aerospace Center Gravity Recovery and Climate Experiment (Grace), reflect California's extended drought and increased rates of groundwater being pumped for human uses, such as irrigation.

In research being presented this week at the American Geophysical Union meeting in San Francisco, scientists from NASA and the University of California, Irvine, detailed California's groundwater changes and outlined Grace-based research on other global aquifers. The twin Grace satellites monitor tiny month-to-month changes in Earth's gravity field primarily caused by the movement of water in Earth's land, ocean, ice and atmosphere reservoirs. Grace's ability to directly 'weigh' changes in water content provides new insights into how Earth's water cycle may be changing.

Combined, California's Sacramento and San Joaquin drainage basins have shed more than 30 cubic kilometers of water since late 2003, said professor Jay Famiglietti of the University of California, Irvine. A cubic kilometer is about 264.2 billion gallons, enough to fill 400,000 Olympic-size pools. The bulk of the loss occurred in California's agricultural Central Valley. The Central Valley receives its irrigation from a combination of groundwater pumped from wells and surface water diverted from elsewhere.

"Grace data reveal groundwater in these basins is being pumped for irrigation at rates that are not sustainable if current trends continue," Famiglietti said. "This is leading to declining water tables, water shortages, decreasing crop sizes and continued land subsidence. The findings have major implications for the U.S. economy, as California's Central Valley is home to one sixth of all U.S. irrigated land, and the state leads the nation in agricultural production and exports."

"By providing data on large-scale groundwater depletion rates, Grace can help California water managers make informed decisions about allocating water resources," said Grace Project Scientist Michael Watkins of NASA's Jet Propulsion Laboratory, Pasadena, Calif., which manages the mission for NASA's Science Mission Directorate, Washington.

Preliminary studies show most of the water loss is coming from the more southerly located San Joaquin basin, which gets less precipitation than the Sacramento River basin farther north. Initial results suggest the Sacramento River basin is losing about 2 cubic kilometers of water a year. Surface water losses account for half of this, while groundwater losses in the northern Central Valley add another 0.6 cubic kilometers annually. The San Joaquin Basin is losing 3.5 cubic kilometers a year. Of this, more than 75 percent is the result of groundwater pumping in the southern Central Valley, primarily to irrigate crops.

Famiglietti said recent California legislation decreasing the allocation of surface waters to the San Joaquin Basin is likely to further increase the region's reliance on groundwater for irrigation. "This suggests the decreasing groundwater storage trends seen by Grace will continue for the foreseeable future," he said.

The California results come just months after a team of hydrologists led by Matt Rodell of NASA's Goddard Space Flight Center, Greenbelt, Md., found groundwater levels in northwest India have declined by 17.7 cubic kilometers per year over the past decade, a loss due almost entirely to pumping and consumption of groundwater by humans.

"California and India are just two of many regions around the world where Grace data are being used to study droughts, which can have devastating impacts on societies and cost the U.S. economy $6 to $8 billion annually," said Rodell. Other regions under study include Australia, the Middle East - North Africa region and the southeastern United States, where Grace clearly captured the evolution of an extended drought that ended this spring. In the Middle East - North Africa region, Rodell is leading an effort to use Grace and other data to systematically map water- and weather-related variables to help assess regional water resources. Rodell added Grace may also help predict droughts, since it can identify pre-existing conditions favorable to the start of a drought, such as a deficit of water deep below the ground.

NASA is working with the National Oceanic and Atmospheric Administration and the University of Nebraska-Lincoln to incorporate Grace data into NOAA's U.S. and North American Drought Monitors, premier tools used to minimize drought impacts. The tools rely heavily on precipitation observations, but are limited by inadequate large-scale observations of soil moisture and groundwater levels. "Grace is the only satellite system that provides information on these deeper stores of water that are key indicators of long-term drought," Rodell said.

Grace is a partnership of NASA and the German Aerospace Center (DLR). The University of Texas Center for Space Research, Austin, has overall mission responsibility. JPL developed the satellites. DLR provided the launch, and GeoForschungsZentrum Potsdam, Germany, operates the mission. For more on Grace, see http://www.csr.utexas.edu/grace/ and http://grace.jpl.nasa.gov/ . Other media contacts: Margaret Baguio, University of Texas Center for Space Research, 512-471-6922; Jennifer Fitzenberger, University of California, Irvine, 949-824-3969.

JPL is managed for NASA by the California Institute of Technology in Pasadena.

- end -

posted in Astronomy - 1 reply

New Star in Big Dipper

idea1407 — Thu, 10 Dec 2009 18:16:48 GMT

http://www.space.com/scienceastronomy/091209-big-dipper-new-star.html

>"New Star Found in Big Dipper
By SPACE.com Staff

posted: 09 December 2009
09:16 pm ET

The Big Dipper has a new star.

One of the stars that makes the bend in the ladle's handle, Alcor, has a smaller red dwarf companion, new observations have revealed.

Alcor is a relatively young star twice the mass of the Sun. Stars this massive are relatively rare (less than a few percent of all stars), short-lived, and bright.

Alcor and its cousins in the Big Dipper formed from the same cloud of matter about 500 million years ago, something unusual for a constellation since most of these patterns in the sky are composed of unrelated stars.

Alcor looks to be in the same position in the Big Dipper with another star, Mizar from the perspective of a viewer on Earth. In fact, both stars were used as a common test of eyesight — being able to distinguish "the rider from the horse" (as the two stars are unofficially known) — for ancient Arab, Roman and English warriors. (Mizar is the brighter of the two stars and can still be seen with the naked eye, while Alcor, a little fainter, would take relatively dark skies to see.)

One of Galileo's colleagues observed that Mizar itself is actually a double, the first binary star system resolved by a telescope. Many years later, the two components Mizar A and B were themselves determined each to be tightly orbiting binaries, altogether forming a quadruple system.

Now, Alcor, which is about 3 light-years away from the four stars of the Mizar system, also has a companion.

Watching for movement

In March, a group of astronomers attached a coronograph and adaptive optics to the 200-inch Hale Telescope at the Palomar Observatory in California and pointed it to Alcor. (Adaptive optics counteract interference from Earth's atmosphere by making swift, real-time changes in the shape of a telescope's mirror during observations.)

"Right away I spotted a faint point of light next to the star," said Neil Zimmerman, a graduate student who is working on his Ph.D. with the American Museum of Natural History in New York. "No one had reported this object before, and it was very close to Alcor, so we realized it was probably an unknown companion star."

A few months later, the team looked at the star again, hoping to prove that the two stars were companions by mapping the tiny movement of both in relation to very distant background stars as the Earth moves around the Sun, or parallactic motion. If the proposed companion were just a background star, it wouldn't move along with Alcor.

"We went back 103 days later and found the companion had the same motion as Alcor," said Ben R. Oppenheimer, Curator and Professor in the Department of Astrophysics at AMNH.

Alcor and its newly found, smaller companion, Alcor B, are both about 80 light-years away from Earth and orbit each other every 90 years or more.

Color and size

The team was also able to determine the color, brightness and even rough composition of Alcor B because the novel method of observation they use records images at many different colors simultaneously. The team determined that Alcor B is a common type of M-dwarf star or red dwarf that is about 250 times the mass of Jupiter, or roughly a quarter of the mass of our Sun. The companion is much smaller and cooler than Alcor A.

"Red dwarfs are not commonly reported around the brighter higher mass type of star that Alcor is, but we have a hunch that they are actually fairly common," Oppenheimer said. "This discovery shows that even the brightest and most familiar stars in the sky hold secrets we have yet to reveal."

The new observations are detailed in the Astrophysical Journal.

Oppenheimer and his team hope to use the same technique of looking for parallactic motion in the search for exoplanets.

"We hope to use the same technique to check that other objects we find like exoplanets are truly bound their host stars," Zimmerman said. "In fact, we anticipate other research groups hunting for exoplanets will also use this technique to speed up the discovery process.""<

posted in Astronomy - 2 replies

Any Guess about the "Norway Spiral?"

Hummingbird — Wed, 09 Dec 2009 17:55:33 GMT

http://www.universetoday.com/2009/12/09/weird-giant-spiral-seen-in-sky-over-norway/

It consisted initially of a green beam of light similar in colour to the aurora with a mysterious rotating spiral at one end," said another eyewitness, Nick Banbury of Harstad, quoted on Spaceweather.com. "This spiral then got bigger and bigger until it turned into a huge halo in the sky with the green beam extending down to the earth. According to the press, this could be seen all over northern norway and must therefore have been very high up in the atmosphere to be seen hundreds of km apart

posted in Astronomy - 5 replies

MRO ressurected

idea1407 — Thu, 10 Dec 2009 18:08:41 GMT

http://www.space.com/missionlaunches/091209-mro-glitch-update.html

>"NASA Finally Resurrects Sick Mars Orbiter
By SPACE.com Staff

posted: 09 December 2009
12:22 pm ET

NASA has finally revived its most powerful Mars orbiter from its months-long slumber due to a computer glitch.

The spacecraft, NASA's Mars Reconnaissance Orbiter, slipped into a protective "safe mode" in late August, stalling its science observations but safeguarding the $720 million probe from further damage. Instead of rousing the orbiter within a few days, as in past glitches, NASA engineers spent months trying to find the source of the probe's inexplicable computer rebooting malfunctions.

"The patient is out of danger, but more steps have to be taken to get it back on its feet," said Jim Erickson, the spacecraft's project manager at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif.

JPL engineers beamed the 4-year-old orbiter a vital software upgrade last week to patch a potentially mission-killing scenario in the spacecraft's onboard computer. That scenario, the unlikely occurrence of back-to-back computer reboots, could have sent the powerful Mars orbiter offline for good, mission managers said.

The satellite's resurrection began Nov. 30 with the software update, and new commands are being sent this week to check the spacecraft's science operations. Actual science observations may resume in earnest next week, mission managers said.

Computer glitches have plagued the Mars Reconnaissance Orbiter this year. In addition to the latest computer reboot in August, the probe suffered similar malfunctions in February and June. Engineers initially thought they were caused by cosmic rays or solar particles interfering with the probe's electronics. In August, the orbiter also unexpectedly switched to a backup computer, a different kind of malfunction, for a short while.

The Mars Reconnaissance Orbiter is NASA's youngest spacecraft orbiting the red planet and the most powerful probe ever to observe the Martian surface. The orbiter launched in 2005 and arrived at Mars in 2006. Since then, it has beamed more data and images of the planet to Earth than all other Mars missions in history combined.

The spacecraft completed its primary mission in late 2008 and is currently in the middle of an extended mission that runs through mid-2010.

It is not the only Mars probe to encounter difficulties this year. NASA's Mars rover Spirit has been stuck wheels-deep in Martian sand since April. Engineers at JPL have been trying several methods of extricating it, but have been waylaid by wheel stall and tilt issues."<

posted in Astronomy - 1 reply

Junk is in the air....er...orbit

idea1407 — Thu, 10 Dec 2009 17:51:21 GMT

http://www.space.com/news/091208-space-junk-cleanup-meeting.html

>" NASA, DARPA Host Space Junk Wake-Up Call
By Leonard David
SPACE.com’s Space Insider Columnist
posted: 08 December 2009
11:24 am ET

Outer space has become Earth's largest junkyard.

It is an international dumping ground for derelict spacecraft, wreckage from colliding satellites, remains from mischievous anti-satellite testing, spent rocket stages, discarded lens caps and clamp bands, paint chips and, yes, at one point, even a lost-to-space tool bag.

All that riff-raff might be out of sight, but it is far from being out of mind. This week, experts from around the world are attending a wake-up call type of meeting.

NASA and the Defense Advanced Research Projects Agency (DARPA) have teamed up to take a hard look at the issues and challenges of de-cluttering space of human-made orbital debris. The result: A first-of-its-kind International Conference on Orbital Debris Removal is being held today through Dec. 10 in Chantilly, Va.

Wanted: innovative solutions

Understanding the space debris problem is one thing. Hammering out viable operational concepts to eliminate the rubbish is another. Then toss in legal and economic issues, as well as incentives. And for good measure add to the brew international policy and cooperation requirements.

For many years NASA has considered means to "remediate" the near-Earth space environment, that is, removing human-made flotsam from Earth orbit – at both low and high altitudes, said Nicholas Johnson, chief scientist of NASA's Orbital Debris Program Office at Johnson Space Center in Houston, Texas.

"We have also evaluated the feasibility of numerous concepts proposed by other U.S. government organizations, the aerospace industry, academia, and the general public," Johnson told SPACE.com. "To date, none of the techniques examined have proven entirely practical due to technical and/or economic reasons."

Johnson said that, earlier this year NASA and DARPA – which is renowned for its innovative solutions to exceptionally difficult problems – agreed to host this week's international conference devoted solely to the subject of orbital debris removal.

More than 50 presentations from the United States, Russia, France, Germany, and Japan will be offered to address not only the technical and economic challenges, but also the legal and policy issues associated with orbital debris removal.

To promote the reliable operation of space systems in the near term, the removal of small orbital debris is of principal interest.

"To preserve the near-Earth space environment for the farther term, the removal of large debris...derelict spacecraft and launch vehicle stages, is required," Johnson observed. "Consequently, a variety of orbital debris removal techniques will likely be necessary to handle the entire spectrum of orbital debris sizes at all altitudes."

Tragedy of the commons

Indeed, over the years various schemes have been aired to deal with the untidiness of orbital debris, be it huge aerogel-laden puff balls to snare debris, various types of galloping gotcha tethers, even vacuum cleaner-type contraptions.

"This is a tragedy of the commons kind of thing," said Jerome Pearson, President of Star Technology and Research, Inc. in Mount Pleasant, S.C. "No one country is responsible for cleaning up space."

Pearson is a strong advocate for a roving space vehicle based on his work to fashion a propellant-less electrodynamic thruster system. This ElectroDynamic Debris Eliminator (EDDE) vehicle, he said, is the only viable method known for the plucking from space of large debris.

EDDE would be maneuverable, flying from place to place in low Earth orbit. This concept is reusable with each vehicle capable of removing many targets by simple debris capture, utilizing lightweight nets or a grappler.

Pearson, however, flags a knotty issue.

"You can't just go up there and move somebody's stuff without permission," Pearson said. "Anything that can go up and grab a piece of debris and bring it down...well, it can also grab somebody's operational satellite and bring it down. That's a space weapon," he cautioned.

What's needed is some kind of international agreement, Pearson said. "There's a lot to be done there. I think it may be more political...more diplomatic than technical," he added.

Umbrella of technologies

One proposal to be aired at the conference is a revisit of Project Orion – an idea that received a NASA technical look in the 1990s.

The scheme uses rapid-fire laser pulses to blow off a micro-thin surface layer of targeted debris. That tiny bit of blow-off acts as a miniature rocket motor. It's enough oomph to tease the object's perigee – low point of its orbit – to where the Earth's atmospheric drag takes hold of the object, reentering the refuse to a fiery finale.

The concept of orbital debris removal via laser – whether by ground-based equipment, an airborne facility, or a space-based system – has greatly advanced over the years, said Jonathan Campbell, a physicist at NASA's Marshall Space Flight Center in Huntsville, Ala.

Campbell said that one of the principle findings from the earlier Project Orion appraisal that he managed was that ground-based laser removal was feasible and affordable in the context of spaceflight budgets. At a cost of only a couple of thousand dollars per object removed, this remains true, he added.

Thanks to the continued progress in laser and associated sensor technologies, Campbell's view is that the ground-based laser approach should be even more effective and affordable than in the 1990's.

Campbell said that, while all technologies have their niche as partial solutions to the orbital debris problem, there's a sizeable load of lethal objects in low Earth orbit. That being the case, he said, only laser technologies offer any hope of removing hundreds of thousands of objects economically in a reasonable timeframe.

"There are some 300,000 objects larger than one centimeter...and they are all moving at hyper-velocity. The only way to address this huge population is with laser technology," Campbell noted. "Orbital debris removal is a complex problem, one that will require an umbrella of technologies to do a complete solution," he stated.

Tough conundrum

At this week's meeting, space law specialist, James Dunstan, along with Bob Werb of the Space Frontier Foundation are set to call for an Orbital Debris Removal and Recycling Fund.

It's the belief of Werb and Dunstan that the current legal regime creates perverse economic incentives that are greatly aggravating the problem of orbital debris. The quickest and surest path to resolving the problem, they contend, is to establish a legal and economic environment that places a high price on anyone generating new debris while simultaneously creating adequate rewards for anyone who mitigates debris.

"From the predictions I've seen of how the space debris population will grow in the coming years, it looks like the space community will need to take active measures soon to clean up at least some of the existing debris, or the problem could get away from us," said Robert Hoyt, leader of Tethers Unlimited, Inc. of Bothell, Wash.

Hoyt is bringing to the DARPA/NASA event his notion tagged "RUSTLER", short for Round Up Space Trash Low Earth orbit Remediation. It too makes use of a propellant-less electrodynamic tether, he said, along with two other unconventional technologies to enable safe and cost-effective removal of defunct satellites, spent upper stages, and other debris from orbit.

"The question has always been who is going to pay to clean up the mess? Nobody really wants to get stuck with that bill," Hoyt said. How you distribute the cost fairly among the many nations and commercial entities that utilize space is a tough conundrum to address, he admitted.

"It's the communities that agree to share the cost of keeping their cities and environment clean that are able to prosper," Hoyt suggested. "The international space community is going to have to come to that same sort of agreement if it is going to prosper in the long term."

Paradigm shift

An upshot of this week's confab of gab by experts is bound to be what next?

For one, there's likely to be a multiple-choice of technologies that appear worth further study. Actual in-space testing of debris removal ideas also seems to be in the cards. Also, what space debris targets are good candidates?

All this means money.

"The conference is what I consider a paradigm shift. We're moving from defining the problem to looking for real solutions," said Campbell.

Given this paradigm shift, Campbell said he was hopeful of seeing increased funding in this area as time goes along. "There's a need to turn this trend around in the growth of space debris. It's going to take some time to do it. But we seem to be heading in the right direction now," he concluded.

* Video - The Expanding Danger of Space Junk
* Video - When Satellites Collide
* Some of the Worst Space Debris Moments"<

posted in Astronomy - 1 reply

Saturn's Mysterious Hexagon Emerges from Winter Darkness

Serge — Wed, 09 Dec 2009 20:16:50 GMT

Jia-Rui C. Cook, 818-354-0850
Jet Propulsion Laboratory, Pasadena, Calif.
jia-rui.c.cook@jpl.nasa.gov

Joe Mason, 720-974-5859
Space Science Institute, Boulder, Colo.
jmason@ciclops.org

Image/Video Advisory:2009-187 December 9, 2009

The full version of this story with accompanying images is at: http://www.jpl.nasa.gov/news/news.cfm?release=2009-187&cid=advisory_2009-187

After waiting years for the sun to illuminate Saturn's north pole again, cameras aboard NASA's Cassini spacecraft have captured the most detailed images yet of the intriguing hexagon shape crowning the planet.

The new images of the hexagon, whose shape is the path of a jet stream flowing around the north pole, reveal concentric circles, curlicues, walls and streamers not seen in previous images. Images and the three-frame animation are available at http://www.nasa.gov/cassini , http://saturn.jpl.nasa.gov and http://ciclops.org .

The last visible-light images of the entire hexagon were captured by NASA's Voyager spacecraft nearly 30 years ago, the last time spring began on Saturn. After the sunlight faded, darkness shrouded the north pole for 15 years. Much to the delight and bafflement of Cassini scientists, the location and shape of the hexagon in the latest images match up with what they saw in the Voyager pictures.

"The longevity of the hexagon makes this something special, given that weather on Earth lasts on the order of weeks," said Kunio Sayanagi, a Cassini imaging team associate at the California Institute of Technology. "It's a mystery on par with the strange weather conditions that give rise to the long-lived Great Red Spot of Jupiter."

The hexagon was originally discovered in images taken by the Voyager spacecraft in the early 1980s. It encircles Saturn at about 77 degrees north latitude and has been estimated to have a diameter wider than two Earths. The jet stream is believed to whip along the hexagon at around 100 meters per second (220 miles per hour).

Early hexagon images from Voyager and ground-based telescopes suffered from poor viewing perspectives. Cassini, which has been orbiting Saturn since 2004, has a better angle for viewing the north pole. But the long darkness of Saturnian winter hid the hexagon from Cassini's visible-light cameras for years. Infrared instruments, however, were able to obtain images by using heat patterns. Those images showed the hexagon is nearly stationary and extends deep into the atmosphere. They also discovered a hotspot and cyclone in the same region.

The visible-light cameras of Cassini's imaging science subsystem, which have higher resolution than the infrared instruments and the Voyager cameras, got their long-awaited glimpse of the hexagon in January, as the planet approached equinox. Imaging team scientists calibrated and stitched together 55 images to create a mosaic and three-frame movie. The mosaics do not show the region directly around the north pole because it had not yet fully emerged from winter night at that time.

Scientists are still trying to figure out what causes the hexagon, where it gets and expels its energy and how it has stayed so organized for so long. They plan to search the new images for clues, taking an especially close look at the newly identified waves that radiate from the corners of the hexagon -- where the jet takes its hardest turns -- and the multi-walled structure that extends to the top of Saturn's cloud layer in each of the hexagon's six sides. Scientists are also particularly intrigued by a large dark spot that appeared in a different position in a previous infrared image from Cassini. In the latest images, the spot appears in the 2 o'clock position.

Because Saturn does not have land masses or oceans on its surface to complicate weather the way Earth does, its conditions should give scientists a more elementary model to study the physics of circulation patterns and atmosphere, said Kevin Baines, an atmospheric scientist at NASA's Jet Propulsion Laboratory, Pasadena, Calif., who has studied the hexagon with Cassini's visual and infrared mapping spectrometer.

"Now that we can see undulations and circular features instead of blobs in the hexagon, we can start trying to solve some of the unanswered questions about one of the most bizarre things we've ever seen in the solar system," Baines said. "Solving these unanswered questions about the hexagon will help us answer basic questions about weather that we're still asking about our own planet."

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of Caltech, manages the Cassini mission for NASA's Science Mission Directorate, Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo.

- end -

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posted in Astronomy - 2 replies

Instant galaxy, just beam it!

idea1407 — Tue, 01 Dec 2009 19:06:09 GMT

http://www.space.com/scienceastronomy/091130-black-hole-galaxies.html

>"Presto! Black Hole Creates a Galaxy
By Clara Moskowitz
Staff Writer
posted: 30 November 2009
04:47 pm ET

Astronomers have long wondered which came first, the black hole or the galaxy around it. The leading theory holds that the two co-evolve, starting small and building over time.

But colossal black holes may zap galaxies into existence from scratch, new observations suggest.

Astronomers recently observed a peculiar large black hole that did not belong to a surrounding galaxy as expected. Until now, scientists thought that this black hole's host galaxy was merely shrouded in dust and rendered invisible to us.

The black hole, designated HE0450-2958, is located about 5 billion light-years away from Earth. It is a type of supermassive black hole known as a quasar, which releases extremely bright jets of high-energy light.

Researchers used the European Southern Observatory's Very Large Telescope to capture new observations of the quasar targeted to search for dust in long-wavelength infrared light.

"Observing at these wavelengths would allow us to trace dust that might hide the host galaxy," said Knud Jahnke of the Max Planck Institute for Astronomy in Heidelberg, Germany, who led the observations. "However, we did not find any. Instead we discovered that an apparently unrelated galaxy in the quasar's immediate neighborhood is producing stars at a frantic rate."

The astronomers think the black hole is powering star formation in the nearby galaxy by spraying its jets of high-energy particles toward it. In fact, the quasar could have triggered the galaxy's formation in the first place when its energetic jets hit nearby clouds of gas. And as time goes on, the neighboring galaxy will likely grow to encompass the black hole at last.

"The two objects are bound to merge in the future: The quasar is moving at a speed of only a few tens of thousands of kilometers per hour with respect to the companion galaxy, and their separation is only about 22,000 light-years," said researcher David Elbaz of the Service d'Astrophysique, CEA Saclay in France. "Although the quasar is still 'naked,' it will eventually be 'dressed' when it merges with its star-rich companion. It will then finally reside inside a host galaxy like all other quasars."

The astronomers detailed their findings in a paper published recently in the journal Astronomy & Astrophysics and an upcoming paper in the Astrophysical Journal."<

Did the Universe read sci-fi, cause this is so right out of Star Trek or something of the kind.

posted in Astronomy - 1 reply

Scientists Explain Puzzling Lake Asymmetry on Titan

Serge — Mon, 30 Nov 2009 23:22:48 GMT

Jia-Rui C. Cook 818-354-0850
Jet Propulsion Laboratory, Pasadena, Calif.
jia-rui.c.cook@jpl.nasa.gov

Stephen Cole 202-657-2194
Headquarters, Washington
stephen.e.cole@nasa.gov

News release: 2009-180 Nov. 30, 2009

The full version of this story with accompanying images is at: http://www.jpl.nasa.gov/news/news.cfm?release=2009-180&cid=release_2009-180

PASADENA, Calif. -- Researchers at the California Institute of Technology, NASA's Jet Propulsion Laboratory, and other institutions suggest that the eccentricity of Saturn's orbit around the sun may be responsible for the unusually uneven distribution of lakes over the northern and southern polar regions of the planet's largest moon, Titan. A paper describing the theory appears in the Nov. 29 advance online edition of Nature Geoscience.

Saturn's oblong orbit around the sun exposes different parts of Titan to different amounts of sunlight, which affect cycles of precipitation and evaporation in those areas. Similar variations in Earth's orbit also drive long-term ice-age cycles on our planet.

As revealed by Synthetic Aperture Radar imaging data from NASA's Cassini spacecraft, liquid methane and ethane lakes in Titan's northern high latitudes cover 20 times more area than lakes in the southern high latitudes. The Cassini data also show there are significantly more partially filled and now-empty lakes in the north. (In the radar data, smooth features -- like the surfaces of lakes -- appear as dark areas, while rougher features -- such as the bottom of an empty lake-appear bright.) The asymmetry is not likely to be a statistical fluke because of the large amount of data collected by Cassini in its five years surveying Saturn and its moons.

Scientists initially considered the idea that "there is something inherently different about the northern polar region versus the south in terms of topography, such that liquid rains, drains or infiltrates the ground more in one hemisphere," said Oded Aharonson of Caltech, lead author of the Nature Geoscience paper.

However, Aharonson notes that there are no substantial known differences between the north and south regions to support this possibility. Alternatively, the mechanism responsible for this regional dichotomy may be seasonal. One year on Titan lasts 29.5 Earth years. Every 15 Earth years, the seasons of Titan reverse, so that it becomes summer in one hemisphere and winter in the other. According to this seasonal variation hypothesis, methane rainfall and evaporation vary in different seasons -- recently filling lakes in the north while drying lakes in the south.

The problem with this idea, Aharonson said, is that it accounts for decreases of about one meter per year in the depths of lakes in the summer hemisphere. But Titan's lakes are a few hundred meters deep on average, and wouldn't drain (or fill) in just 15 years. In addition, seasonal variation can't account for the disparity between the hemispheres in the number of empty lakes. The north polar region has roughly three times as many dried-up lake basins as the south and seven times as many partially filled ones.

"How do you move the hole in the ground?" Aharonson asked. "The seasonal mechanism may be responsible for part of the global transport of liquid methane, but it's not the whole story." A more plausible explanation, say Aharonson and his colleagues, is related to the eccentricity of the orbit of Saturn -- and hence of Titan, its satellite -- around the sun.

Like Earth and other planets, Saturn's orbit is not perfectly circular, but is instead somewhat elliptical and oblique. Because of this, during its southern summer, Titan is about 12 percent closer to the sun than during the northern summer. As a result, northern summers are long and subdued; southern summers are short and intense.

"We propose that, in this orbital configuration, the difference between evaporation and precipitation is not equal in opposite seasons, which means there is a net transport of methane from south to north," said Aharonson. This imbalance would lead to an accumulation of methane -- and hence the formation of many more lakes -- in the northern hemisphere.

This situation is only true right now, however. Over very long time scales of tens of thousands of years, Saturn's orbital parameters vary, at times causing Titan to be closer to the sun during its northern summer and farther away in southern summers, and producing a reverse in the net transport of methane. This should lead to a buildup of hydrocarbon -- and an abundance of lakes -- in the southern hemisphere.

"Like Earth, Titan has tens-of-thousands-of-year variations in climate driven by orbital motions," Aharonson said. On Earth, these variations, known as Milankovitch cycles, are linked to changes in solar radiation, which affect global redistribution of water in the form of glaciers, and are believed to be responsible for ice-age cycles. "On Titan, there are long-term climate cycles in the global movement of methane that make lakes and carve lake basins. In both cases we find a record of the process embedded in the geology," he added.

"We may have found an example of long-term climate change, analogous to Milankovitch climate cycles on Earth, on another object in the solar system," he said.

The paper's co-authors are Caltech graduate student Alexander G. Hayes; Jonathan I. Lunine, Lunar and Planetary Laboratory, Tucson, Ariz.; Ralph D. Lorenz, Applied Physics Laboratory at the Johns Hopkins University, Laurel, Md.; Michael D. Allison, NASA Goddard Institute for Space Studies, New York; and Charles Elachi, director of JPL. The work was partially funded by the Cassini Project.

For more information about the Cassini-Huygens mission, visit: http://www.nasa.gov/cassini or http://saturn.jpl.nasa.gov/index.cfm . The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate in Washington, D.C.

- end -

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posted in Astronomy - 1 reply

Solar Tsunamis

idea1407 — Thu, 26 Nov 2009 23:46:20 GMT

http://www.space.com/scienceastronomy/091125-solar-tsunami.html

>"Solar Tsunamis Are Real, NASA Says
By SPACE.com staff

posted: 25 November 2009
11:18 am ET

Incredibly powerful waves of plasma rippling across the surface of the sun and dubbed "solar tsunamis" were first observed years ago, but were thought to be an optical illusion. Scientists have now confirmed, though, that they are really real.

When scientists first saw the phenomenon, it was hard to believe that a towering wave of hot plasma was actually racing along the sun's surface. One of the waves rose up higher than the diameter of Earth and rippled out from a central point in a circular pattern millions of miles wide, like a gargantuan pattern of waves created by a pebble dropped in a pond.

Skeptical observers suggested it might be a shadow of some kind – a trick of the eye. But new observations from NASA's STEREO (Solar Terrestrial Relations Observatory) spacecraft are telling researchers that this controversial phenomenon isn't an illusion.

This week, NASA released a remarkable video of a solar tsunami.

"Now we know," said Joe Gurman of the Solar Physics Lab at NASA's Goddard Space Flight Center in Greenbelt, Md. "Solar tsunamis are real."

Reality confirmed

The twin STEREO spacecraft confirmed their reality in images captured in February when sunspot 11012 unexpectedly erupted. The blast hurled a billion-ton cloud of gas (a coronal mass ejection, or "CME") into space and sent a tsunami racing along the sun's surface.

STEREO recorded the wave from two positions separated by 90 degrees, giving researchers an unprecedented view of the event.

"It was definitely a wave," said Spiros Patsourakos of George Mason University in Virginia and lead author of a paper reporting the finding in the Astrophysical Journal Letters. "Not a wave of water," he adds, "but a giant wave of hot plasma and magnetism."

The technical name is "fast-mode magnetohydrodynamical wave" – or "MHD wave" for short. The one STEREO saw reared up about 62,000 miles (100,000 km) high, and raced outward at 560,000 mph (250 km/s) packing as much energy as 2,400 megatons of TNT.

Solar tsunamis were discovered back in 1997 by the Solar and Heliospheric Observatory (SOHO). In May of that year, a CME blasted up from an active region on the sun's surface, and SOHO recorded a tsunami rippling away from the blast site.

"We wondered," Gurman recalled, "is that a wave – or just a shadow of the CME overhead?"

Stereo view

SOHO's single point of view was not enough to answer the question–neither for that first wave nor for many similar events recorded by SOHO in years that followed, until STEREO launched in 2006. The mission uses two spacecraft — one orbiting the sun ahead of the Earth, the other behind it — to get, literally, a stereo view of the sun.

"We've seen the waves reflected by coronal holes (magnetic holes in the sun's atmosphere)," Vourlidas said. "And there is a wonderful movie of a solar prominence oscillating after it gets hit by a wave. We call it the 'dancing prominence.'"

Solar tsunamis pose no direct threat to Earth. Nevertheless, they are important to study, scientists say.

"We can use them to diagnose conditions on the sun," Gurman said. "By watching how the waves propagate and bounce off things, we can gather information about the sun's lower atmosphere available in no other way."

"Tsunami waves can also improve our forecasting of space weather," Vourlidas added, "Like a bull-eye, they 'mark the spot' where an eruption takes place. Pinpointing the blast site can help us anticipate when a CME or radiation storm will reach Earth.""<

posted in Astronomy - 1 reply

Utah Fireball on Police Video

Hummingbird — Tue, 24 Nov 2009 18:16:55 GMT

http://blogs.discovermagazine.com/badastronomy/2009/11/24/police-camera-catches-utah-fireball/

posted in Astronomy - 7 replies

Breaking: LCROSS Finds Lunar Water

Hummingbird — Fri, 13 Nov 2009 17:48:31 GMT

http://www.cnn.com/2009/TECH/space/11/13/water.moon.nasa/index.html

(CNN) -- NASA has discovered water on the moon, based on data from the Lunar Crater Observation and Sensing Satellite, or LCROSS, that plunged into the moon last month, the principal investigator for LCROSS said Friday.

Anthony Colaprete said at the start of his comments to reporters, "Indeed, yes, we found water."

"The discovery opens a new chapter in our understanding of the moon," NASA said in a written statement.

posted in Astronomy - 14 replies

Jupiter

Serge — Fri, 20 Nov 2009 02:25:19 GMT

Jupiter is INSANE today.
It's all over the sky. I have never seen it that big!

Look South.

posted in Astronomy - 2 replies

Cassini's Big Sky - The View from the Center of Our Solar System

Serge — Fri, 20 Nov 2009 19:24:39 GMT

Feature Nov 19, 2009

The full version of this story with accompanying images is at:
http://www.jpl.nasa.gov/news/features.cfm?feature=2370

When NASA's Cassini spacecraft began orbiting Saturn five years ago, a dozen highly-tuned science instruments set to work surveying, sniffing, analyzing and scrutinizing the Saturnian system.

But Cassini recently revealed new data that appeared to overturn the decades-old belief that our solar system resembled a comet in shape as it moves through the interstellar medium (the matter between stars in our corner of the Milky Way galaxy).

Instead, the new results suggest our heliosphere more closely resembles a bubble – or a rat – being eaten by a boa constrictor: as the solar system passes through the "belly" of the snake, the ribs, which mimic the local interstellar magnetic field, expand and contract as the rat passes. An animation is available here http://photojournal.jpl.nasa.gov/catalog/PIA12310.

"At first I was incredulous," said Tom Krimigis, principal investigator of the Magnetospheric Imaging Instrument (MIMI) at Johns Hopkins University's Applied Physics Laboratory in Laurel, Md. "The first thing I thought was, 'What's wrong with our data?'"

Krimigis and his colleagues on the instrument team published the Cassini findings in the Nov. 13 issue of the journal Science, which featured complementary results from NASA's Interstellar Boundary Explorer (IBEX). Together, the results create the first map of the heliosphere and its thick outer layer known as the heliosheath, where solar wind streaming out from the sun gets heated and slowed as it interacts with the interstellar medium.

The Cassini data also provide a much more direct indication of the thickness of the heliosheath, whereas scientists previously had to rely on calculations from models. The new results from Cassini show that the heliosheath is about 40 to 50 astronomical units (3.7 billion to 4.7 billion miles) thick and that NASA's twin Voyager spacecraft, which are traveling through the heliosheath now, will cross into true interstellar space well before the year 2020. Estimates as far out as 2030 had been suggested.

"These new data from Cassini really redefine our sense of our home in the galaxy, and we can now do better studies of whether our solar system resembles those elsewhere," Krimigis said.

The Voyagers have sent back rich data on the heliosphere and heliosheath, but just at two locations. Scientists want more context. One way to learn about the region is to track energetic neutral atoms streaming back toward the sun from the heliosheath.

Energetic neutral atoms form when cold, neutral gas collides with electrically-charged particles in a cloud of plasma, which is a gas-like state of matter so hot that the atoms split into an ion and an electron. The positively-charged ions in plasma can't reclaim their own electrons, which are moving too fast, but they can steal an electron from the cold gas atoms. Since the resulting particles are neutrally charged, they are able to escape magnetic fields and zoom off into space. The emission of these particles often occurs in the magnetic fields surrounding planets, but also happens when the solar wind mingles with the interstellar medium.

How did Cassini, with 22,000 wire connections and 14 kilometers (8.7 miles) of cabling specifically tweaked to get the most out of its investigation of the solar system's second largest gas bag, recently end up helping to redefine how we look at our entire solar system?

Krimigis and his Cassini colleagues working with MIMI weren't sure their instrument could pick up emissions from far-out, exotic locations, such as from the boundary of our heliosphere, the region of our sun's influence.

Last year, after spending four years focused on the energetic electrons and ions trapped in the magnetic field that surrounds Saturn, as well as the offspring of these particles known as energetic neutral atoms, the team started combing through the data from the instrument's Ion and Neutral Camera, looking for particles arriving from far beyond Saturn.

"We thought we could get some hits from energetic neutral atoms from the heliosheath because Cassini has really been in an excellent position to detect these particles," said Don Mitchell, MIMI instrument scientist and a researcher at the Applied Physics Laboratory.

Cassini was farther away from the sun than previous spacecraft trying to image the heliosphere and even swung very far away from Saturn on some of its orbits, Mitchell said. The data would likely be free of much of the interference that hampered other efforts.

Mitchell, Krimigis and their team were able to stitch together data from late 2003 to the summer of 2009. They created a color-coded map of the intensity of the energetic neutral atoms and discovered a belt of hot, high-pressure particles where the interstellar wind flowed by our heliosheath bubble.

The data matched up nicely with the IBEX images of lower-energy particles and connected that data set to the Voyager data on higher-energy particles.

"I was initially skeptical because the instrument was designed for Saturn's magnetosphere," Mitchell said, "But our camera had long exposures of months to years, so we could accumulate and map each particle that streamed through the tiny aperture from the far reaches of the heliosphere. It was luck, but also a lot of hard work."

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, Calif. manages the mission for NASA's Science Mission Directorate, Washington, D.C.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov and http://www.nasa.gov/cassini .

-end-

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posted in Astronomy - 0 replies

Leonid shower peeking

idea1407 — Tue, 17 Nov 2009 02:23:15 GMT

http://www.space.com/spacewatch/091116-leonid-meteor-shower-2009.html

>"Strong Leonid Meteor Shower Peaks Early Tuesday Morning
By Robert Roy Britt
Editorial Director
posted: 16 November 2009
08:01 am ET

One of the best annual meteor showers will peak in the pre-dawn hours Tuesday, and for some skywatchers the show could be quite impressive.

The best seats are in Asia, but North American observers should be treated to an above average performance of the Leonid meteor shower, weather permitting. The trick for all observers is to head outside in the wee hours of the morning – between 1 a.m. and dawn – regardless where you live.

The Leonids put on a solid show every year, if skies are clear and moonlight does not interfere. This year the moon is near its new phase, and not a factor. For anyone in the Northern Hemisphere with dark skies, away from urban and suburban lighting, the show should be worth getting up early to see.

"We're predicting 20 to 30 meteors per hour over the Americas, and as many as 200 to 300 per hour over Asia," said Bill Cooke of NASA's Meteoroid Environment Office. Other astronomers who work in the nascent field of meteor shower prediction have put out similar forecasts.

Urban dwellers and suburbanites will see far fewer, as the fainter meteors will be drowned out by local lights.

Behind the Leonids

The Leonids are created by the comet Tempel-Tuttle, which passes through the inner solar system every 33 years on its orbit around the sun. Each time by, it leaves a new river of debris, mostly bits of ice and rock no bigger than a sand grain but a few the size of a pea or marble.

Over time, these cosmic streams spread out, so predicting exactly what will happen is difficult.

"We can predict when Earth will cross a debris stream with pretty good accuracy," Cooke said. "The intensity of the display is less certain, though, because we don't know how much debris is in each stream."

When Earth plows into the debris, the bits hit the atmosphere and vaporize, creating sometimes dramatic streaks of light and the occasional fireball with a smoky-looking trail that can remain visible for several minutes.

The Leonid stream is moving in the opposite direction of Earth, producing impact speeds of 160,000 mph (72 kilometers per second) – higher than many other meteors.

"Such speeds tend to produce meteors with hues of white, blue, aquamarine and even green," says Joe Rao, SPACE.com's skywatching columnist.

How to watch

The best viewing will be in rural areas. Get out of town if you can. If you have local lights, scout a location in advance where the lights are blocked by a building, tree or hill.

Dress warmly, and take a blanket or lounge chair so you can lie back and scan as much of the sky as possible. "At this time of year, meteor watching can be a long, cold business," Rao reminds people.

Leonids can appear anywhere, but if you trace them back, they all point to a hub, or radiant, in the constellation Leo – hence the name.

Give your eyes 15 minutes to adjust to the darkness. Then give the show at least a half-hour. The hourly rates stated above typically come in bursts, with lulls that may test your patience. No special equipment is needed. Telescopes and binoculars are of no use because meteors move too quickly.

When to watch

Earth will pass through one of the denser debris streams at around 4 a.m. EST (1 a.m. PST) Tuesday. If you have only an hour or less to watch, center it around this time. Leo will be high in the sky for East Coast skywatchers, putting more meteors into view. In the West, Leo will be low in the eastern sky at this time, so fewer shooting stars will be above the horizon, and therefore Western skywatchers should also try to stick it out until daybreak.

Across Europe, the best bet is to watch anytime between 1 a.m. and daybreak local time.

The planet will pass through an even denser stream later, just before dawn Wednesday in Indonesia and China, but that show won't be visible from North America because it will be daytime here.

One truth about the Leonids: They always produce, and they sometimes produce spectacular, unforgettable fireballs."<

posted in Astronomy - 7 replies

NASA's Wise Gets Ready to Survey the Whole Sky

Serge — Tue, 17 Nov 2009 19:19:36 GMT

Whitney Clavin 818-354-4673
Jet Propulsion Laboratory, Pasadena, Calif.
Whitney.clavin@jpl.nasa.gov

J.D. Harrington 202-358-5241
NASA Headquarters, Washington
j.d.harrington@nasa.gov

News release: 2009-166 Nov. 17, 2009

The full version of this story with accompanying images is at: http://www.jpl.nasa.gov/news/news.cfm?release=2009-166&cid=kintera_release_2009-166

PASADENA, Calif. -- NASA's Wide-field Infrared Survey Explorer, or Wise, is chilled out, sporting a sunshade and getting ready to roll. NASA's newest spacecraft is scheduled to roll to the pad on Friday, Nov. 20, its last stop before launching into space to survey the entire sky in infrared light.

Wise is scheduled to launch no earlier than 6:09 a.m. PST (9:09 a.m. EST) on Dec. 9 from Vandenberg Air Force Base in California. It will circle Earth over the poles, scanning the entire sky one-and-a-half times in nine months. The mission will uncover hidden cosmic objects, including the coolest stars, dark asteroids and the most luminous galaxies.

"The eyes of Wise are a vast improvement over those of past infrared surveys," said Edward "Ned" Wright, the principal investigator for the mission at UCLA. "We will find millions of objects that have never been seen before."

The mission will map the entire sky at four infrared wavelengths with sensitivity hundreds to hundreds of thousands of times greater than its predecessors, cataloging hundreds of millions of objects. The data will serve as navigation charts for other missions, pointing them to the most interesting targets. NASA's Hubble and Spitzer Space Telescopes, the European Space Agency's Herschel Space Observatory, and NASA's upcoming Sofia and James Webb Space Telescope will follow up on Wise finds.

"This is an exciting time for space telescopes," said Jon Morse, NASA's Astrophysics Division director at NASA Headquarters in Washington. "Many of the telescopes will work together, each contributing different pieces to some of the most intriguing puzzles in our universe."

Visible light is just one slice of the universe's electromagnetic rainbow. Infrared light, which humans can't see, has longer wavelengths and is good for seeing objects that are cold, dusty or far away. In our solar system, Wise is expected to find hundreds of thousands of cool asteroids, including hundreds that pass relatively close to Earth's path. Wise's infrared measurements will provide better estimates of asteroid sizes and compositions -- important information for understanding more about potentially hazardous impacts on Earth.

"With infrared, we can find the dark asteroids other surveys have missed and learn about the whole population. Are they mostly big, small, fluffy or hard?" said Peter Eisenhardt, the Wise project scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif.

Wise also will find the coolest of the "failed" stars, or brown dwarfs. Scientists speculate it is possible that a cool star lurks right under our noses, closer to us than our nearest known star, Proxima Centauri, which is four light-years away. If so, Wise will easily pick up its glow. The mission also will spot dusty nests of stars and swirling planet-forming disks, and may find the most luminous galaxy in the universe.

To sense the infrared glow of stars and galaxies, the Wise spacecraft cannot give off any detectable infrared light of its own. This is accomplished by chilling the telescope and detectors to ultra-cold temperatures. The coldest of Wise's detectors will operate at below 8 Kelvin, or minus 445 degrees Fahrenheit.

"Wise is chilled out," said William Irace, the project manager at JPL. "We've finished freezing the hydrogen that fills two tanks surrounding the science instrument. We're ready to explore the universe in infrared."

JPL manages Wise for NASA's Science Mission Directorate in Washington. The mission was competitively selected under NASA's Explorers Program managed by the Goddard Space Flight Center in Greenbelt, Md. The science instrument was built by the Space Dynamics Laboratory in Logan, Utah, and the spacecraft was built by Ball Aerospace & Technologies Corp. in Boulder, Colo. Science operations and data processing take place at the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena. Caltech manages JPL for NASA.

More information about Wise is available online at http://www.nasa.gov/wise and http://www.jpl.nasa.gov/wise/ .

- end -

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posted in Astronomy - 3 replies

NASA and Microsoft Allow Earthlings to Become Martians

Serge — Tue, 17 Nov 2009 19:17:13 GMT

Guy Webster 818-354-6278
Jet Propulsion Laboratory, Pasadena, Calif.
guy.webster@jpl.nasa.gov

Dwayne Brown 202-358-1726
NASA Headquarters, Washington
dwayne.c.brown@nasa.gov

News release: 2009-167 Nov. 17, 2009

The full version of this story with accompanying images is at: http://www.jpl.nasa.gov/news/news.cfm?release=2009-167&cid=kintera_release_2009-167

PASADENA, Calif. -- NASA and Microsoft Corp. of Redmond, Wash., have collaborated to create a Web site where Internet users can have fun while advancing their knowledge of Mars.

Drawing on observations from NASA's Mars missions, the "Be a Martian" Web site will enable the public to participate as citizen scientists to improve Martian maps, take part in research tasks, and assist Mars science teams studying data about the Red Planet.

"We're at a point in history where everyone can be an explorer," said Doug McCuistion, director of the Mars Exploration Program at NASA Headquarters in Washington. "With so much data coming back from Mars missions that are accessible by all, exploring Mars has become a shared human endeavor. People worldwide can expand the specialized efforts of a few hundred Mars mission team members and make authentic contributions of their own."

Participants will be able to explore details of the solar system's grandest canyon, which resides on Mars. Users can call up images in the Valles Marineris canyon before moving on to chart the entire Red Planet. The collaboration of thousands of participants could assist scientists in producing far better maps, enabling smoother zoom-in views and easier interpretation of Martian surface changes.

By counting craters, the public also may help scientists determine the relative ages of small regions on Mars. In the past, counting Martian craters has posed a challenge because of the vast numbers involved. By contributing, Web site users will win game points assigned to a robotic animal avatar they select.

With a common goal of inspiring digital-age workforce development and life-long learning in science, technology, engineering and mathematics, NASA and Microsoft unveiled the Web site at the Microsoft Professional Developers Conference in Los Angeles this week. The site also beckons software developers to win prizes for creating tools that provide access to and analysis of hundreds of thousands of Mars images for online, classroom and Mars mission team use.

"Industry leaders like NASA and Microsoft have a social responsibility as well as a vested interest in advancing science and technology education," said Walid Abu-Hadba, corporate vice president of the Developer and Platform Evangelism Group at Microsoft. "We are excited to be working with NASA to provide new opportunities to engage with Mars mission data, and to help spark interest and excitement among the next generation of scientists and technologists."

To encourage more public participation, the site also provides a virtual town hall forum where users can expand their knowledge by proposing Mars questions and voting on which are the most interesting to the community. Online talks by Mars experts will address some of the submitted questions. Other features include interactive tools for viewing Martian regions and movies about people who study Mars in diverse ways.

"Mars exploration inspires people of all ages, and we are especially eager to encourage young people to explore Mars for themselves," said Charles Elachi, director of NASA's Jet Propulsion Laboratory in Pasadena, Calif. "We are delighted to be involved in providing the creative opportunity for future explorers to contribute to our understanding of Mars."

"The beauty of this type of experience is that it not only teaches people about Mars and the work NASA is doing there, but it also engages large groups of people to help solve real challenges that computers cannot solve by themselves," said Marc Mercuri, director of business innovation in the Developer and Platform Evangelism Group at Microsoft.

The Mars Exploration Program is managed by JPL for NASA's Science Mission Directorate in Washington.

To enroll as a virtual Martian citizen and start exploring, visit http://beamartian.jpl.nasa.gov . For more exploration on NASA's Mars exploration program, visit http://www.nasa.gov/mars .

JPL is managed for NASA by the California Institute of Technology in Pasadena.

- end -

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posted in Astronomy - 0 replies

Sounds of the planets

Poster_Boy — Tue, 17 Nov 2009 06:07:19 GMT

Has anyone heard this?

As the Voyager and other spacecraft made their way past the gas planets (Jupiter, Saturn, Uranus, Neptune) they were able to pick up radio waves from the planet's surface. Note that these are normal, 'natural' radio waves that the planet emits, picked up as electromagnetic frequencies over NASA's audio equipment. Yes, I'm aware that there is no air in the vacuum of space to conduct sound.

I really like the sounds these planets make. I find it very relaxing and meditative.

This is Neptune.
http://www.youtube.com/watch?v=rwnpXll_A_E&feature=related

Saturn
http://www.youtube.com/watch?v=gf-X3EWNxh4&feature=related

I think that Jupiter is my favorite.
http://www.youtube.com/watch?v=ZU7_oymmiNI&feature=related

posted in Astronomy - 1 reply

NASA to Begin Attempts to Free Sand-Trapped Mars Rover

Serge — Fri, 13 Nov 2009 02:59:48 GMT

Guy Webster 818-354-6278
Jet Propulsion Laboratory, Pasadena, Calif.
guy.webster@jpl.nasa.gov

Dwayne Brown 202-358-1726
NASA Headquarters, Washington
dwayne.c.brown@nasa.gov

News release: 2009-164, Nov. 12, 2009

The full version of this story with accompanying images is at: http://www.jpl.nasa.gov/news/news.cfm?release=2009-164

PASADENA, Calif. -- NASA will begin transmitting commands to its Mars exploration rover Spirit on Monday as part of an escape plan to free the venerable robot from its Martian sand trap.

Spirit has been lodged at a site scientists call "Troy" since April 23. Researchers expect the extraction process to be long and the outcome uncertain based on tests here on Earth this spring that simulated conditions at the Martian site.

"This is going to be a lengthy process, and there's a high probability attempts to free Spirit will not be successful" said Doug McCuistion, director of the Mars Exploration Program at NASA Headquarters in Washington. "After the first few weeks of attempts, we're not likely to know whether Spirit will be able to free itself."

Spirit has six wheels for roving the Red Planet. The first commands will tell the rover to rotate its five working wheels forward approximately six turns. Engineers anticipate severe wheel slippage, with barely perceptible forward progress in this initial attempt. Since 2006, Spirit's right-front wheel has been inoperable, possibly because of wear and tear on a motor as a result of the rover's longevity.

Spirit will return data the next day from its first drive attempt. The results will be assessed before engineers develop and send commands for a second attempt. Using results from previous commands, engineers plan to continue escape efforts until early 2010.

"Mobility on Mars is challenging, and whatever the outcome, lessons from the work to free Spirit will enhance our knowledge about how to analyze Martian terrain and drive future Mars rovers," McCuisition said. "Spirit has provided outstanding scientific discoveries and shown us astounding vistas during its long life on Mars, which is more than 22 times longer than its designed life. "

In the spring, Spirit was driving backward and dragging the inoperable right front wheel. While driving in April, the rover's other wheels broke through a crust on the surface that was covering a bright-toned, slippery sand underneath. After a few drive attempts to get Spirit out in the subsequent days, it began sinking deeper in the sand trap. Driving was suspended to allow time for tests and reviews of possible escape strategies.

"The investigations of the rover embedding and our preparations to resume driving have been extensive and thorough," said John Callas, project manager for Spirit and Opportunity at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "We've used two different test rovers here on Earth in conditions designed to simulate as best as possible Spirit's predicament. However, Earth-based tests cannot exactly replicate the conditions at Troy."

Data show Spirit is straddling the edge of a 26-foot-wide crater that had been filled long ago with sulfate-bearing sands produced in a hot water or steam environment. The deposits in the crater formed distinct layers with different compositions and tints, and they are capped by a crusty soil. It is that soil that Spirit's wheels broke through. The buried crater lies mainly to Spirit's left. Engineers have plotted an escape route from Troy that heads up a mild slope away from the crater.

"We'll start by steering the wheels straight and driving, though we may have to steer the wheels to the right to counter any downhill slip to the left," said Ashley Stroupe, a JPL rover driver and Spirit extraction testing coordinator. "Straight-ahead driving is intended to get the rover's center of gravity past a rock that lies underneath Spirit. Gaining horizontal distance without losing too much vertical clearance will be a key to success. The right front wheel's inability to rotate greatly increases the challenge."

Spirit has been examining its Martian surroundings with tools on its robotic arm and its camera mast. The rover's work at Troy has augmented earlier discoveries it made indicating ancient Mars had hot springs or steam vents, possible habitats for life. If escape attempts fail, the rover's stationary location may result in new science findings.

"The soft materials churned up by Spirit's wheels have the highest sulfur content measured on Mars," said Ray Arvidson a scientist at Washington University in St. Louis and deputy principal investigator for the science payloads on Spirit and Opportunity. "We're taking advantage of its fixed location to conduct detailed measurements of these interesting materials."

Spirit and its twin rover landed on Mars in January 2004. They have explored Mars for five years, far surpassing their original 90-day mission. Opportunity currently is driving toward a large crater called Endeavor.

NASA's JPL manages the rovers for NASA's Science Mission Directorate in Washington.

For updates about Spirit's progress, visit: http://www.nasa.gov/rovers or http://marsrovers.jpl.nasa.gov/home/index.html

- end -

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posted in Astronomy - 6 replies

Top Ten Lunar Impacts

Hummingbird — Thu, 08 Oct 2009 13:34:49 GMT

http://www.space.com/scienceastronomy/080320-top10-mooncrashes.html

Ten natural and human caused impacts.

posted in Astronomy - 3 replies

Space Elevator

Curry — Sat, 07 Nov 2009 02:50:31 GMT

Going Up? Top Floor, Space Elevator Games 2009
BREAKING NEWS: LaserMotive successfully qualified for the $900,000 prize! Their official speed was 3.72 m/s.
Though it's unlikely that anyone will be pressing the elevator button labeled 'Space' on one of the competitors' vehicles this year at the 2009 Space Elevator Games, there is hope that a winner will walk away with the $1.1 million prize. Three different teams will compete to see if any can send a laser powered vehicle up a thin but strong ribbon 1km (.6 miles) into the sky.(...)

http://www.universetoday.com/2009/11/04/going-up-top-floor-space-elevator-games-2009/

posted in Astronomy - 1 reply

Enceladus geysers

idea1407 — Wed, 04 Nov 2009 16:16:51 GMT

http://www.space.com/scienceastronomy/091104-enceladus-plumes.html

>"Water Geysers on Saturn Moon Take Center Stage
By Clara Moskowitz
Staff Writer
posted: 04 November 2009
09:32 am ET

Striking new photos of water-vapor geysers erupting from Saturn's moon Enceladus were beamed to Earth this week by NASA's Cassini spacecraft in orbit around the ringed planet.

Cassini made its deepest dive yet into the plumes pouring out from the moon's south pole on Nov. 2 during a planned flyby of Enceladus. The spacecraft approached within about 62 miles (100 km) of the moon's surface.

The powerful plumes, which contain water vapor, sodium and organic chemicals such as carbon dioxide, look a bit like the Old Faithful geyser in Yellowstone National Park. They have intrigued scientists because they suggest that a store of liquid water may be present beneath the moon's crust to give rise to the water vapor in the plumes. And if there is liquid water, there might be the possibility of some kind of alien life.

"If we can put the pieces together - a liquid ocean under the surface, heat driving the geysers and the organic molecules that are the building blocks of life - Enceladus might turn out to have the conditions that led to the origin of life on an earlier version of Earth," Cassini scientist Bonnie J. Buratti wrote on NASA's Jet Propulsion Laboratory blog.

The aim of the recent flyby - Cassini's seventh targeted swoop toward Enceladus - was to measure the size, mass, charge, speed and composition of the particles within the plume. The spacecraft made a quick approach traveling at about 18,000 mph (nearly 29,000 kph). In addition to the scientific data, the spacecraft returned new stunning snapshots showing the enigmatic geysers glowing in reflected sunlight against the dark backdrop of space.

"Not too bad being in orbit around Saturn, is it ?! ;-)" wrote Carolyn Porco, head of Cassini's imaging science team, via Twitter. Porco called the images "spectacular."

The joint U.S.-European Cassini spacecraft was launched in 1997 on a mission to orbit Saturn, and discovered the geysers on Enceladus in 2005. The spacecraft completed its primary mission in 2008 and is currently in the middle of an extended phase that runs through 2010. <CHECK THIS!!!

"This is the first time we've found activity on a moon this small," Buratti wrote, explaining that Enceladus is only about the width of Arizona, with a diameter of 310 miles (500 km)."<

pic:
http://www.space.com/php/multimedia/imagedisplay/img_display.php?pic=091104-enceladus-02.jpg&cap=This+raw%2C+unprocessed+image+of+Enceladus+was+taken+by+Cassini+on+Nov.+2%2C+2009.+Bright+plumes+of+water+vapor+are+visible+on+the+moon%27s+south+pole.+Credit%3A+NASA%2FJPL%2FSpace+Science+Institute

pic:
http://www.space.com/php/multimedia/imagedisplay/img_display.php?pic=091104-plumes-02.jpg∩=Geysers+on+the+Saturnian+moon+Enceladus.+Photo+taken+by+the+Cassini+spacecraft%27s+narrow-angle+camera+on+Nov.+1%2C+2009+using+a+spectral+filter+sensitive+to+wavelengths+of+near-infrared+light.+Credit%3A+NASA%2FJPL%2FSpace+Science+Institute

pic:
http://www.space.com/php/multimedia/imagedisplay/img_display.php?pic=091104-geysers-02.jpg∩=Bright+water-vapor+plumes+glisten+on+Enceladus+in+this+image+taken+in+visible+light+with+the+Cassini+spacecraft+narrow-angle+camera+on+Nov.+1%2C+2009.+Credit%3A+NASA%2FJPL%2FSpace+Science+Institute

posted in Astronomy - 1 reply

LCROSS has eyes on target

idea1407 — Fri, 11 Sep 2009 19:12:35 GMT

http://www.nasa.gov/home/hqnews/2009/sep/HQ_09-210_LCROSS_Crater_Selection.html

>"RELEASE : 09-210

NASA's LCROSS Reveals Target Crater For Lunar South Pole Impacts

MOFFETT FIELD, Calif. – NASA has selected a final destination for its Lunar Crater Observation and Sensing Satellite, or LCROSS, after a journey of nearly 5.6 million miles that included several orbits around Earth and the moon. The mission team announced Wednesday that Cabeus A will be the target crater for the LCROSS dual impacts scheduled for 7:30 a.m. EDT on Oct. 9, 2009. The crater was selected after an extensive review as the optimal location for LCROSS' evaluation of whether water ice exists at the lunar south pole.

LCROSS will search for water ice by sending its spent upper-stage Centaur rocket to impact the permanently shadowed polar crater. The satellite will fly into the plume of dust left by the impact and measure the properties before also colliding with the lunar surface. The LCROSS team selected Cabeus A based on a set of conditions that include proper debris plume illumination for visibility from Earth, a high concentration of hydrogen, and mature crater features such as a flat floor, gentle slopes and the absence of large boulders.

"The selection of Cabeus A was a result of a vigorous debate within the lunar science community that included review of the latest data from Earth-based observatories and our fellow lunar missions Kaguya, Chandrayaan-1, and the Lunar Reconnaissance Orbiter," said Anthony Colaprete, LCROSS project scientist and principle investigator at NASA’s Ames Research Center in Moffett Field, Calif. "The team is looking forward to the impacts and the wealth of information this unique mission will produce."

A cadre of professional astronomers using many of the Earth's most capable observatories is helping maximize the scientific return from the LCROSS impacts. These observatories include the Infrared Telescope Facility and Keck telescope in Hawaii; the Magdalena Ridge and Apache Ridge Observatories in New Mexico and the MMT Observatory in Arizona; the newly refurbished Hubble Space Telescope; and the Lunar Reconnaissance Orbiter, among others.

"These and several other telescopes participating in the LCROSS Observation Campaign will provide observations from different vantage points using different types of measurement techniques," said Jennifer Heldmann, lead for the LCROSS Observation Campaign at Ames. "These multiple observations will complement the LCROSS spacecraft data to help determine whether or not water ice exists in Cabeus A."

During a media briefing Sept. 11, Daniel Andrews, LCROSS project manager at Ames, provided a mission status update indicating the spacecraft is healthy and has enough fuel to successfully accomplish all mission objectives. Andrews also announced the dedication of the LCROSS mission to the memory of legendary news anchor, Walter Cronkite, who provided coverage of NASA's missions from the beginning of America's manned space program to the age of the space shuttle.

"Dad would sure be proud to be part, if just in name, of getting humans back up to the moon and beyond," said Chip Cronkite, son of the famed news anchor.

The LCROSS mission was selected in April 2006 as a mission manifested with the Lunar Reconnaissance Orbiter. Both missions launched on June 18, 2009 on an Atlas V from Cape Canaveral, Fla. The LCROSS mission and science operations are managed at Ames.

"The LCROSS team has long been preparing for its final destination on the moon, and we're looking forward to October 9," Andrews said. "The next 28 days will undoubtedly be very exciting.""<

posted in Astronomy - 5 replies

Frost-Covered Phoenix Lander Seen in Winter Images

Serge — Thu, 05 Nov 2009 01:19:46 GMT

Guy Webster 818-354-6278
Jet Propulsion Laboratory, Pasadena, Calif.
guy.webster@jpl.nasa.gov

News release: 2009-160, Nov. 4, 2009

The full version of this story with accompanying images is at: http://www.jpl.nasa.gov/news/news.cfm?release=2009-160

PASADENA, Calif. -- Winter images of NASA's Phoenix Lander showing the lander shrouded in dry-ice frost on Mars have been captured with the High Resolution Imaging Science Experiment, or HiRISE camera, aboard NASA's Mars Reconnaissance Orbiter.

The HiRISE camera team at the University of Arizona, Tucson, captured one image of the Phoenix lander on July 30, 2009, and the other on Aug. 22, 2009. That's when the sun began peeking over the horizon of the northern polar plains during winter, the imaging team said. The first day of spring in the northern hemisphere began Oct. 26.

The images are available at http://hirise.lpl.arizona.edu/ESP_014393_2485 .

"We decided to try imaging the site despite the low light levels," said HiRISE team member Ingrid Spitale of the University of Arizona Lunar and Planetary Laboratory.

"The power of the HiRISE camera helped us see it even under these poor light conditions," added HiRISE team member Michael Mellon of the University of Colorado in Boulder, who was also on the Phoenix Mars Lander science team.

The HiRISE team targeted their camera at the known location of the lander to get the new images and compared them to a HiRISE image of the frost-free lander taken in June 2008. That enabled them to identify the hardware disguised by frost, despite the fact that their views were hindered by poor lighting and by atmospheric haze, which often obscures the surface at this location and season.

Carbon dioxide frost completely blankets the surface in both images. The amount of carbon dioxide frost builds as late winter transitions to early spring, so the layer of frost is thicker in the Aug. 22 image.

HiRISE scientists noted that brightness doesn't necessarily indicate the amount of frost seen in the images because of the way the images are processed to produce optimal contrast. Even the darker areas in the frost-covered images are still brighter than typical soil that surrounds the lander in frost-free images taken during the lander's prime mission in 2008.

Other factors that affect the relative brightness include the size of the individual grains of carbon dioxide ice, the amount of dust mixed with the ice, the amount of sunlight hitting the surface and different lighting angles and slopes, Spitale and Mellon said.

Studying these changes will help us understand the nature of the seasonal frost and winter weather patterns in this area of Mars.

Scientists predicted that the ice layer would reach maximum thickness in September 2009, but don't have images to confirm that because HiRISE camera operations were suspended when Mars Reconnaissance Orbiter entered an extended safe mode on Aug. 26.

The Phoenix Mars Lander ceased communications last November, after successfully completing its mission and returning unprecedented primary science phase and returning science data to Earth. During the first quarter of 2010, teams at JPL will listen to see if Phoenix is still able to communicate with Earth. Communication is not expected and is considered highly unlikely following the extended period of frost on the lander.

HiRISE is run from the Lunar and Planetary Laboratory's HiRISE Operations Center, on the University of Arizona campus. Planetary Sciences Professor Alfred McEwen is HiRISE principal investigator. Planetary Sciences Professor Peter Smith is principal investigator for the Phoenix Mars Lander mission. The Mars Reconnaissance Orbiter is managed by NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, for NASA Science Mission Directorate, Washington. Lockheed Martin Space Systems, based in Denver, is the prime contractor and built the spacecraft. Ball Aerospace Technologies Corp., of Boulder, Colo., built the HiRISE camera.

For more information about the mission, visit: http://www.nasa.gov/mro .

-end-

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posted in Astronomy - 2 replies

Galaxy cluster and Universe's Skeleton

idea1407 — Wed, 04 Nov 2009 03:16:44 GMT

http://www.space.com/scienceastronomy/091103-galaxies-cosmic-web.html

>"Huge Galaxy Cluster Hints at Universe's Skeleton
By SPACE.com staff

posted: 03 November 2009
08:42 am ET

A gigantic, previously unknown set of galaxies has been found in the distant universe, shedding light on the underlying skeleton of the cosmos.

"Matter is not distributed uniformly in the universe," said Masayuki Tanaka, an astronomer with the European Southern Observatory (ESO) who helped discover the galactic assemblage. "In our cosmic vicinity, stars form in galaxies and galaxies usually form groups and clusters of galaxies."

But those collections of matter are just small potatoes compared to larger structures long-theorized to exist.

"The most widely accepted cosmological theories predict that matter also clumps on a larger scale in the so-called 'cosmic web,' in which galaxies, embedded in filaments stretching between voids, create a gigantic wispy structure," Tanaka said.

These filaments are millions of light-years long and constitute the skeleton of the universe: Galaxies gather around them, and immense galaxy clusters form at their intersections, lurking like giant spiders waiting for more matter to digest.

Scientists have struggled, though, to explain how the filaments come into existence. While massive filamentary structures have often been observed at relatively small distances from us, solid proof of their existence in the more distant universe has been lacking until now.

The team led by Tanaka discovered a large structure around a distant cluster of galaxies in images they had taken earlier. They have now used two major ground-based telescopes to study this structure in greater detail, measuring the distances from Earth to more than 150 galaxies, and, hence, obtaining a three-dimensional view of the structure.

The spectroscopic observations, detailed in the Astronomy & Astrophysics Journal, were performed using the VIMOS instrument on ESO's Very Large Telescope in Chile and FOCAS on the Subaru Telescope in Hawaii, operated by the National Astronomical Observatory of Japan.

With these observations, the astronomers identified several groups of galaxies surrounding the main galaxy cluster.

The researchers were able to distinguish tens of such clumps, each typically ten times as massive as our own Milky Way galaxy — and some as much as a thousand times more massive — while they estimate that the mass of the cluster amounts to at least ten thousand times the mass of the Milky Way.

Some of the clumps are feeling the fatal gravitational pull of the cluster, and will eventually fall into it, the data suggested.

This information will allow scientists to explore how galaxies were affected by their environment at a time when the universe was much younger.

The filament is located about 6.7 billion light-years away from us and extends over at least 60 million light-years. The newly uncovered structure does probably extend farther, beyond the field probed by the team, and hence future observations have already been planned to obtain a definite measurement of its size."<

posted in Astronomy - 2 replies

Mercury's Seasons

idea1407 — Wed, 04 Nov 2009 04:01:44 GMT

http://www.space.com/scienceastronomy/091103-mercury-new-images.html

>"NASA Probe Sees Changing Seasons on Mercury
By Andrea Thompson
Senior Writer
posted: 03 November 2009
02:58 pm ET

A NASA spacecraft has spotted what appears to be changing seasons on Mercury and found much more iron on the surface of the small, rocky planet than previously thought.

The MESSENGER probe made the observations during its third flyby of Mercury on Sept. 29, when it took a host of measurements and images of the innermost planet's surface and atmosphere. Only about half of the planned measurements were made because of a data glitch that affected the spacecraft during the flyby.

The $446 million probe's third flyby brought it within 142 miles (228 km) of Mercury's surface to cover more uncharted terrain, leaving 98 percent of the planet now mapped. The flyby was also a gravity assist meant to guide the spacecraft into orbit around the planet in 2011.

Tenuous exosphere

Mercury's atmosphere is what scientists call an "exosphere," and is made up of atoms kicked up from the surface. It is very tenuous and has a very low density, meaning atoms in the atmosphere rarely run into each other. It also has a tail that streams away from the planet in the opposite direction of the sun.

MESSENGER looked at differences in three atoms in the exosphere — sodium, calcium and magnesium — between the probe's three flybys. They detected much less sodium during the third flyby than they had during the second.

"While this is dramatic, it isn't totally unexpected," Vervack said. This is because radiation pressures from the sun change as Mercury moves through its orbit, which changes the amount of sodium liberated from the surface.

In essence, Mercury's atmosphere experiences seasonal effects during the planet's orbit.

Calcium and magnesium showed less variation between "seasons" than did sodium, showing that different atoms "are going to have their own unique seasonal varations," Vervack said.

Understanding these seasonal differences will help scientists understand how surface material is lost and how the surface has changed over time.

Mercury's atmosphere is "the end product of a few billion years of these processes, they never stop," said mission scientist Ronald Vervack, Jr., of The Johns Hopkins University Applied Physics Laboratory (JHUAPL) in Laurel, Md.

Surface surprises

The MESSENGER flybys also provided the first direct measurements of the amounts of certain elements on Mercury's surface.

Mercury's surface has long thought to be deficient in the heavy metals iron and titanium on the basis of earlier observations, an ironic make-up considering that its heavy iron core makes up an estimated 60 percent of the planet's mass and makes it the densest of the solar system's rock planets.

MESSENGER's observations show that Mercury's surface actually possesses relatively high numbers of these elements — similar to the concentrations in the moon's nearside maria basalts — which could mean that models on the planets formation and evolution will need to be revised.

"That's a pretty exciting result for us," said David Lawrence, also of JHUAPL.

The third flyby also yielded new images of the surface that fill in as-yet unobserved areas. The spacecraft's cameras and instruments collected high-resolution and color images unveiling another 6 percent of the planet's surface never before seen at close range.

"We've done a good job on filling in most of that map," said Brett Denevi, imaging team member and postdoctoral researcher at Arizona State University in Tempe.

The flyby garnered images of a feature seen before, but not in enough detail to characterize it. It appears to be a bright area surrounding an irregular depression, with steep sides and an odd shape, "all of which are hallmarks of something like a volcanic vent," Denevi said.

Other images revealed a double-ring impact basin approximately 180 miles across. The basin is similar to a feature scientists call the Raditladi basin, which was viewed during the probe's first flyby of Mercury in January 2008.

"One similarity to Raditladi is its age, which has been estimated to be approximately one billion years old. Such an age is quite young for an impact basin, because most basins are about four times older," Denevi said. "The inner floor of this basin is even younger than the basin itself and differs in color from its surroundings. We may have found the youngest volcanic material on Mercury."

The spacecraft has completed nearly three-quarters of its 4.9-billion-mile journey to enter orbit around Mercury. The full trip will include more than 15 trips around the sun. In addition to flying by Mercury, the spacecraft flew past Earth in August 2005 and Venus in October 2006 and June 2007."<

Pic:
http://www.space.com/php/multimedia/imagedisplay/img_display.php?pic=091103-mercury-map-02.jpg&cap=Image+coverage+map+of+Mercury+after+the+third+MESSENGER+flyby.+he+nearly+complete+%2898+percent%29+coverage+now+leaves+unimaged+only+portions+of+the+polar+regions+before+MESSENGER+is+placed+into+orbit+about+Mercury+in+March+2011.+Credit%3A+JHU%2FAPL%2FNASA

posted in Astronomy - 1 reply

Galaxy Cluster 10 Billion Light Years Distant

Hummingbird — Thu, 22 Oct 2009 16:55:56 GMT

http://blogs.discovermagazine.com/badastronomy/2009/10/22/cluster-tucked-at-the-far-reaches-of-the-universe/

"A cluster of galaxies recently observed by three different telescopes now holds the record for the most distant ever seen: 10.2 billion light years, a solid billion light years farther away than the previous record holder!"

From Phil Plait's "Bad Astronomy" blog. One of the top notch blogs about astronomy on the internet.

posted in Astronomy - 5 replies

GRB, Fermi, Relativity and Quantum Mechanics - Observed!

idea1407 — Fri, 30 Oct 2009 23:03:56 GMT

a must see from NASA.

http://www.youtube.com/watch?v=1mkKhn53L68

posted in Astronomy - 0 replies

Robot Armada Might Scale New Worlds

Serge — Wed, 28 Oct 2009 04:55:53 GMT

Feature, Oct. 27, 2009

The full version of this story with accompanying images is at: http://www.jpl.nasa.gov/news/features.cfm?feature=2343

An armada of robots may one day fly above the mountain tops of Saturn's moon Titan, cross its vast dunes and sail in its liquid lakes.
Wolfgang Fink, visiting associate in physics at the California Institute of Technology in Pasadena says we are on the brink of a great paradigm shift in planetary exploration, and the next round of robotic explorers will be nothing like what we see today.

"The way we explore tomorrow will be unlike any cup of tea we've ever tasted," said Fink, who was recently appointed as the Edward and Maria Keonjian Distinguished Professor in Microelectronics at the University of Arizona, Tucson. "We are departing from traditional approaches of a single robotic spacecraft with no redundancy that is Earth-commanded to one that allows for having multiple, expendable low-cost robots that can command themselves or other robots at various locations at the same time."

Fink and his team members at Caltech, the U.S. Geological Survey and the University of Arizona are developing autonomous software and have built a robotic test bed that can mimic a field geologist or astronaut, capable of working independently and as part of a larger team. This software will allow a robot to think on its own, identify problems and possible hazards, determine areas of interest and prioritize targets for a close-up look.

The way things work now, engineers command a rover or spacecraft to carry out certain tasks and then wait for them to be executed. They have little or no flexibility in changing their game plan as events unfold; for example, to image a landslide or cryovolcanic eruption as it happens, or investigate a methane outgassing event.

"In the future, multiple robots will be in the driver's seat," Fink said. These robots would share information in almost real time. This type of exploration may one day be used on a mission to Titan, Mars and other planetary bodies. Current proposals for Titan would use an orbiter, an air balloon and rovers or lake landers.

In this mission scenario, an orbiter would circle Titan with a global view of the moon, with an air balloon or airship floating overhead to provide a birds-eye view of mountain ranges, lakes and canyons. On the ground, a rover or lake lander would explore the moon's nooks and crannies. The orbiter would "speak" directly to the air balloon and command it to fly over a certain region for a closer look. This aerial balloon would be in contact with several small rovers on the ground and command them to move to areas identified from overhead.

"This type of exploration is referred to as tier-scalable reconnaissance," said Fink. "It's sort of like commanding a small army of robots operating in space, in the air and on the ground simultaneously."

A rover might report that it's seeing smooth rocks in the local vicinity, while the airship or orbiter could confirm that indeed the rover is in a dry riverbed -- unlike current missions, which focus only on a global view from far above but can't provide information on a local scale to tell the rover that indeed it is sitting in the middle of dry riverbed.

A current example of this type of exploration can best be seen at Mars with the communications relay between the rovers and orbiting spacecraft like the Mars Reconnaissance Orbiter. However, that information is just relayed and not shared amongst the spacecraft or used to directly control them.

"We are basically heading toward making robots that command other robots," said Fink, who is director of Caltech's Visual and Autonomous Exploration Systems Research Laboratory, where this work has taken place.

"One day an entire fleet of robots will be autonomously commanded at once. This armada of robots will be our eyes, ears, arms and legs in space, in the air, and on the ground, capable of responding to their environment without us, to explore and embrace the unknown," he added.

Papers describing this new exploration are published in the journal "Computer Methods and Programs in Biomedicine" and in the Proceedings of the SPIE.

For more information on this work, visit http://autonomy.caltech.edu . More information on JPL missions is at http://www.jpl.nasa.gov/ .

JPL is managed for NASA by the California Institute of Technology.

Media contact: Carolina Martinez/JPL 818-354-9382

-end-

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JPL's 'Green' Space Flight Building Debuts with Ribbon-Cutting

Serge — Tue, 27 Oct 2009 03:08:50 GMT

Elena Mejia/Mark Petrovich 818-393-5467/393-4359
Jet Propulsion Laboratory, Pasadena, Calif.
Elena.Mejia@jpl.nasa.gov / Mark.Petrovich@jpl.nasa.gov

News release: 2009-157, Oct. 26, 2009

The full version of this story with accompanying images is at: http://www.jpl.nasa.gov/news/news.cfm?release=2009-157

NASA's "greenest" building to date -- an environmentally friendly Flight Projects Center at NASA's Jet Propulsion Laboratory in Pasadena, Calif. -- is now open for business, following a ribbon-cutting ceremony today attended by lawmakers and local dignitaries.

The building houses missions during their design and development phases. It will enable engineers and scientists from various countries to collaborate more closely during these critical mission phases.

"It seems fitting that the new building, where teams will plan future space missions that use new technologies, also has the latest 'green' technologies to help JPL do its part to improve our environment here on Earth," said JPL Director Charles Elachi, who helped cut the ribbon at today's ceremony.

Also attending today's ceremony were U.S. Rep. David Drier; La Canada-Flintridge Mayor Laura Olhasso; staff representing U.S. Rep. Adam Schiff; and Caltech President Jean-Lou Chameau.

The building has received the "LEED Gold Certification" under the Leadership in Energy and Environmental Design rating system, set up by the non-profit U.S. Green Building Council. It is the first NASA building to achieve that certification. To qualify, buildings must meet several criteria. For example, they must make efficient use of water, energy and resources, and provide a healthy and comfortable indoor workspace.

The many "green" features of the new building include:

A living roof to keep the building cool in summer months and warm in the winter. Desert plants on the roof and other landscaping require 72 percent less water than a typical Southern California landscape design.

Outdoor lighting is used for safety purposes only and is directed toward the ground, reducing the amount of light pollution that escapes to the night sky.

Low-flow faucets and toilets reduce water use by 40 percent compared with typical fixtures.

Improved wall insulation, efficient chillers and boilers and window shading devices.

The paints and other surface materials have low levels of toxic fumes.

The heating and cooling system is "smart" -- it knows whether people are in a room and adjusts the temperature and ventilation accordingly.

The janitorial staff uses green cleaning products and practices.

More than 75 percent of the waste generated during construction of the new building was diverted from a landfill to a local recycling facility. Wood was acquired from Forest Stewardship Council-certified suppliers, ensuring sustainable harvesting of trees.

More information about the Leadership in Energy and Environmental Design rating system and the U.S. Green Building Council is online at http://www.usgbc.org .

More information about JPL is online at http://www.jpl.nasa.gov . The California Institute of Technology in Pasadena manages JPL for NASA.

- end -

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Free Classes for Teachers: Lunar Certification and Marsbound, (NASA)

Serge — Mon, 26 Oct 2009 18:15:20 GMT

Oct. 26, 2009

What:
The NASA/JPL Education Resources Center is offering FREE classes!

Are you interested in Lunar Certification? This certification allows you to borrow actual lunar rock and soil samples as well as meteorite samples from NASA.

We are also offerring a class on the Marsbound Challenge to the red planet. You have $250 million dollars to plan a mission to the red planet. This game will challenge students to work together just as JPL engineers do. Marsbound meets many California state content standards in math as well as science and technology from 4th grade through high school.

When:
October 27 – Marsbound: 4 p.m. to 5:30 p.m.
November 12 – Lunar Certification: 4 p.m. to 6:00 p.m.

Where:
Educator Resource Center
1460 Holt Ave.
Pomona, CA 91767
909-397-4420

Directions:
Take the Indian Hill exit on U.S. 10. Go south until Indian Hill ends at Holt. Drive into the shopping center straight ahead. (Village @ Indian Hill Mall). Look for mall entrance number 3, park and enter the mall.

Parking is free.

How:
RSVP to the Education Resource Center at 909-397-4420.

See you there!

- end -

From: subscription email

posted in Astronomy - 2 replies

Astronomers do it Again: Find Organic Molecules Around Gas Planet

Serge — Wed, 21 Oct 2009 06:52:20 GMT

Feature, Oct. 20, 2009

The full version of this story with accompanying images is at: http://www.jpl.nasa.gov/news/features.cfm?feature=2340

Peering far beyond our solar system, NASA researchers have detected the basic chemistry for life in a second hot gas planet, advancing astronomers toward the goal of being able to characterize planets where life could exist. The planet is not habitable but it has the same chemistry that, if found around a rocky planet in the future, could indicate the presence of life.

"It's the second planet outside our solar system in which water, methane and carbon dioxide have been found, which are potentially important for biological processes in habitable planets," said researcher Mark Swain of NASA's Jet Propulsion Laboratory, Pasadena, Calif. "Detecting organic compounds in two exoplanets now raises the possibility that it will become commonplace to find planets with molecules that may be tied to life."

Swain and his co-investigators used data from two of NASA's orbiting Great Observatories, the Hubble Space Telescope and Spitzer Space Telescope, to study HD 209458b, a hot, gaseous giant planet bigger than Jupiter that orbits a sun-like star about 150 light years away in the constellation Pegasus. The new finding follows their breakthrough discovery in December 2008 of carbon dioxide around another hot, Jupiter-size planet, HD 189733b. Earlier Hubble and Spitzer observations of that planet had also revealed water vapor and methane.

The detections were made through spectroscopy, which splits light into its components to reveal the distinctive spectral signatures of different chemicals. Data from Hubble's near-infrared camera and multi-object spectrometer revealed the presence of the molecules, and data from Spitzer's photometer and infrared spectrometer measured their amounts.

"This demonstrates that we can detect the molecules that matter for life processes," said Swain. Astronomers can now begin comparing the two planetary atmospheres for differences and similarities. For example, the relative amounts of water and carbon dioxide in the two planets is similar, but HD 209458b shows a greater abundance of methane than HD 189733b. "The high methane abundance is telling us something," said Swain. "It could mean there was something special about the formation of this planet."

Other large, hot Jupiter-type planets can be characterized and compared using existing instruments, Swain said. This work will lay the groundwork for the type of analysis astronomers eventually will need to perform in shortlisting any promising rocky Earth-like planets where the signatures of organic chemicals might indicate the presence of life.

Rocky worlds are expected to be found by NASA's Kepler mission, which launched earlier this year, but astronomers believe we are a decade or so away from being able to detect any chemical signs of life on such a body.

If and when such Earth-like planets are found in the future, "the detection of organic compounds will not necessarily mean there's life on a planet, because there are other ways to generate such molecules," Swain said. "If we detect organic chemicals on a rocky, Earth-like planet, we will want to understand enough about the planet to rule out non-life processes that could have led to those chemicals being there."

"These objects are too far away to send probes to, so the only way we're ever going to learn anything about them is to point telescopes at them. Spectroscopy provides a powerful tool to determine their chemistry and dynamics."

You can follow the history of planet hunting from science fiction to science fact with NASA's PlanetQuest Historic Timeline at http://planetquest.jpl.nasa.gov/timeline/timeline.html .

This interactive web feature, developed by JPL, conveys the story of exoplanet exploration through a rich tapestry of words and images spanning thousands of years, beginning with the musings of ancient philosophers and continuing through the current era of space-based observations by NASA's Spitzer and Kepler missions. The timeline highlights milestones in culture, technology and science, and includes a planet counter that tracks the pace of exoplanet discoveries over time.

More information about exoplanets and NASA's planet-finding program is at http://planetquest.jpl.nasa.gov .

The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency and is managed by NASA's Goddard Space Flight Center in Greenbelt, Md. The Space Telescope Science Institute, Baltimore, Md., conducts Hubble science operations. The institute is operated for NASA by the Association of Universities for research in Astronomy, Inc., Washington, D.C.

JPL manages the Spitzer Space Telescope mission for NASA. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology in Pasadena. Caltech manages JPL for NASA.

-end-

Written by Mary Beth Murrill

Media contact: Whitney Clavin/Jet Propulsion Laboratory 818-354-4671

From: subscription email

posted in Astronomy - 3 replies

Glimpses of Solar System's edge

freetheweed — Thu, 15 Oct 2009 21:11:24 GMT

http://news.bbc.co.uk/2/hi/science/nature/8309179.stm

The first results from Nasa's Interstellar Boundary Explorer (Ibex) spacecraft have shown unexpected features at our Solar System's edge.

Ibex was launched nearly one year ago to map the heliosphere, the region of space defined by the extent of our Sun's solar wind.

Ibex's first glimpses show that the heliosphere is not shaped as many astronomers have believed.

A series of papers in the journal Science outlines the results.

Our Solar System is whipping around the centre of the galaxy. Just like a hand held out of a moving car, the Solar System feels a "wind" of particles from the region between our star and its nearest neighbours.

At the same time, the solar wind - a constant stream of fast-moving particles in all directions - blows outwards from the Sun.

The boundary at which the incoming and outgoing particles are at equivalent pressures, known as the heliopause, defines the heliosphere - the "bubble" in space generated by our own Sun's exhalations.

True shape

The true extent and shape of the heliosphere has been a subject of debate for more than half a century. Until now, the best clues came from the two Voyager spacecraft, which are believed to have passed through the heliopause at two different distances.

Through a process known as "charge exchange" at the heliosphere's edge, fast-moving neutral or uncharged particles are created, and it is these energetic neutral atoms or ENAs that the Ibex spacecraft aims to measure.

It orbits the Earth in a vast ellipse, gathering incoming ENAs flying back from the heliopause at a range of speeds.

What a number of researchers have found is that the flow of the ENAs is uneven, with a significantly higher flow in a "ribbon" across the sky.

"The Ibex results are truly remarkable, with emissions not resembling any of the current theories or models of this never-before-seen region," said lead researcher Dr David McComas of the Southwest Research Institute in New Mexico.

"We expected to see small, gradual spatial variations at the interstellar boundary. However, Ibex is showing us a very narrow ribbon that is two to three times brighter than anything else in the sky."

Near miss

These concentrations of incoming particles were just missed by the Voyager spacecraft, Dr McComas explained.

"The most astounding feature in the Ibex sky maps - the bright narrow ribbon - snakes through the sky between the Voyager spacecraft, where it remained completely undetected until now," he said.

Further measurements were made by the Cassini spacecraft orbiting Saturn. It too has a "camera" that can capture incoming neutral atoms, and also observed a ribbon-shaped region across the sky, but from ENAs moving at slightly different speeds.

What is clear is that the heliosphere is not shaped like a comet, as previously thought, with a head pointed at the oncoming interstellar medium and a tail of matter trailing behind.

The research groups agree that the magnetic field interactions at the heliopause have as-yet undetermined effects on the overall shape. But the exact shape, and the forces that cause it, are still a matter of debate between the teams.

INTERSTELLAR BOUNDARY EXPLORER (IBEX)

*Completes a large, elliptical orbit around the Earth
*Measures uncharged atoms that enter the Solar System from the interstellar medium
*Can detect hydrogen, helium, and oxygen moving at a wide range of speeds through the Solar System
*Results should explain how interstellar magnetic fields form our heliosphere

posted in Astronomy - 5 replies

32 new planets

Curry — Tue, 20 Oct 2009 15:14:17 GMT

October 19th, 2009
HARPS Discovers 32 New Exoplanets
Written by Nancy Atkinson ShareThis

Astronomers have found 32 new planets outside our solar system with the High Accuracy Radial Velocity Planet Searcher, better known as HARPS, the spectrograph for the European Southern Observatory's (ESO) 3.6-metre telescope. The number of known exoplanets is now at 406, and HARPS itself has discovered more than 75 exoplanets in 30 different planetary systems. Included in this most recent batch are several low-mass planets – so-called "Super Earths" about the size of Neptune. The image above is an artist's impression of a planet discovered that is 6 times the mass of Earth, which circles the low-mass host star, Gliese 667 C, at a distance equal to only 1/20th of the Earth-Sun distance. Two other planets were discovered previously around this star.

"HARPS is a unique, extremely high precision instrument that is ideal for discovering alien worlds," said ESO astronomer Stéphane Udry. “We have now completed our initial five-year program, which has succeeded well beyond our expectations.”

No Earth-like planets were discovered in this group that was announced today at an exoplanet conference in Portugal.

HARPS has facilitated the discovery of 24 of the 28 planets known with masses below 21 Earth masses. As with the previously detected super-Earths, most of the new low-mass candidates reside in multi-planet systems, with up to five planets per system. This new group includes a total of 11 planets with masses between 5 and 21 times that of Earth – and 9 in multi-planet systems — and increases the number of known low-mass planets by 30%.

HARPS uses the radial velocity technique which measures the back-and-forward motions of stars by detecting small changes in a star’s radial velocity as it wobbles slightly from a gentle gravitational pull from an otherwise unseen planet. HARPS can detect changes in velocity as small as 3.5 km/hour, a steady walking pace.

Notable discoveries by HARPS during the past five years include the first super-Earth in 2004 (around µ Ara; ESO 22/04); in 2006, the trio of Neptunes around HD 69830 (ESO 18/06); in 2007, Gliese 581d, the first super Earth in the habitable zone of a small star (ESO 22/07); and in 2009, the lightest exoplanet so far detected around a normal star, Gliese 581e (ESO 15/09). More recently, they found a potentially lava-covered world, with density similar to that of the Earth’s (ESO 33/09).

“These observations have given astronomers a great insight into the diversity of planetary systems and help us understand how they can form,” says team member Nuno Santos.

Source: ESO

Filed under: Extrasolar Planets

http://www.universetoday.com/2009/10/19/harps-discovers-32-new-exoplanets/

posted in Astronomy - 0 replies

NASA Finds Plume From LCROSS Impact

Hummingbird — Fri, 16 Oct 2009 23:50:02 GMT

http://www.space.com/scienceastronomy/091016-lcross-plume.html

NASA scientists have finally seen in their data a debris plume created by the impact of a moon probe last week.
The faint plume was seen in the data from the engineered crash one week after the impact of the LCROSS probe.
Scientists are hoping that analysis of the plume will show signs of water ice ejected from the probe's target crater, named Cabeus, at the lunar south pole.

posted in Astronomy - 1 reply

Enceladus water debate

idea1407 — Tue, 13 Oct 2009 22:08:10 GMT

http://www.space.com/scienceastronomy/091013-st-enceladus-debate.html

>"Hot Debate Rages Over Water on Saturn's Icy Moon

By Clara Moskowitz
Astrobiology Magazine
posted: 13 October 2009
08:50 am ET

The recent discovery of plumes containing water vapor erupting from the south pole of the frigid Saturnian moon Enceladus set off a firestorm of debate.

Many scientists thought the geysers of gaseous water must boil out of liquid water stored under the moon's surface, which would make Enceladus a promising candidate for life.

But a new study challenges that conclusion, arguing that the plumes could just as easily come from ice through the process of sublimation - the direct leap from the solid to gaseous state.

This conclusion may dampen Enceladus' astrobiology hopes, though it does not exclude the possibility of liquid water, and thus life, on the moon.

Cold Faithful

Enceladus' geysers were first spotted in 2005 by NASA's Cassini spacecraft, which was launched in 1997 on a mission to orbit Saturn. Shortly after the discovery, a research group led by Carolyn Porco, head of Cassini's imaging science team, calculated the ratio of water ice to vapor in the plumes. Cassini wasn't able to directly measure the masses of ice and vapor in the plumes, but the researchers estimated the mass of ice from the observed brightness of the plumes (because ice reflects light, so the more ice, the brighter the plumes). They deduced the mass of water vapor from a measurement of the molecular signature of vapor in the wavelengths of light Cassini observed from the plumes.

The scientists found that there were almost equal amounts of ice and water vapor. If this is the case, the researchers argued, the plumes cannot result from the sublimation of ice. The ice crystals are believed to be re-condensed from the vapor, rather than directly ejected from the surface or subsurface of the moon. A lot of vapor is needed to produce that 50/50 ice and vapor ratio, but the laws of thermodynamics prevent that much vapor from being produced solely by sublimation. Therefore, some of the vapor must be produced by evaporation rather than sublimation. This means a vast reserve of liquid water must exist on Enceladus, perhaps as shallow as 23 feet (7 m) under the surface. Under this theory, the researchers dubbed Enceladus' plumes "Cold Faithful" after the Old Faithful geyser in Yellowstone National Park. Their paper was published in 2006 in the journal Science.

But a new study led by Susan Kieffer of the University of Illinois at Urbana-Champaign challenges that work. She and her colleagues recalculated the ice-to-vapor ratio and produced vastly different results. Under their calculations, vapor is much more abundant than ice, with their final ratio less than 2:10, compared to the previous team's estimate of 1:1.

"We simply redid the calculations described in the [previous] paper and found that we could not reproduce the results quoted for either the abundance of vapor or the abundance of ice," Kieffer said. "Our conclusion was that sublimation should not have been excluded from consideration as a process that could produce the measured quantities, and thus should be considered as thoroughly as the liquid water hypothesis. Unfortunately, it has not been."

Kieffer and team published their findings in the May 2009 issue of the journal Icarus.

Conflicting interpretations

The two contradicting conclusions paint a vastly different picture of Enceladus. Under the first, the moon has an icy veneer that masks a dynamic region of flowing water under the surface that could possibly host life. But another interpretation sees Enceladus as a frigid world, solid with ice and rock all the way through.

"Water is certainly present in Enceladus, at least as solid and vapor, but the presence of vapor does not necessarily imply that liquid water is present," Kieffer wrote with Brucke Jakosky, a scientist at the University of Colorado in Boulder, in an essay in the June 13, 2008 issue of Science. "A definitive answer about the potential for life may have to await a follow-on spacecraft mission that can make specific high-resolution observations that could distinguish between the competing models."

The authors of the original paper, with the more hopeful outlook on the possibility of liquid water on the moon, agree that more work is needed to solve the conundrum and understand the conflicting estimates of the plumes' ice-to-vapor ratio.

"Serious analysis of the Enceladus plume images are only just beginning on the imaging team, and the jury is still very much out on this subject," Porco said in response to the new paper.

Andrew Ingersoll, a planetary scientist at Caltech, was involved with the original Porco et al. estimate, but said he doesn't believe that either ratio is truly accurate.

"Right now, I am not convinced by anyone's estimates of the ice/vapor ratio," he said. Ingersoll is currently working on a new, revised estimate.

Cassini is also scheduled to make future flybys of the moon, which could help refine the estimates.

"There are a number of reasons that the ice/vapor ratio cannot be used to prove or disprove either model," Kieffer said. "Nevertheless, it was the ice/vapor ratio from the original paper that gave the liquid water hypothesis its momentum. The point of our Icarus paper is that this value was miscalculated, that two competing hypotheses should have been set in motion, and both should still be considered by the scientific community."

The intriguing possibilities and conflicting interpretations of Enceladus are reasons why many scientists are pushing for a dedicated spacecraft mission to the moon. Though no official plans exist, a number of proposals are currently being considered for future NASA and ESA (European Space Agency) missions."<

posted in Astronomy - 1 reply

Saturn's has a very large ring

idea1407 — Wed, 07 Oct 2009 15:06:22 GMT

http://www.space.com/scienceastronomy/091007-saturn-big-ring.html

>"Enormous New Ring Found Distantly Orbiting Saturn
By Andrea Thompson
Senior Writer
posted: 07 October 2009
09:32 am ET

There's a new king of rings in the solar system: An enormous new ring has been discovered around Saturn, made up of debris from the gas giant's distant moon Phoebe.

Before the discovery of this massive ring — about 12.5 times the average distance between the Earth and the moon in width and 6 times that distance in thickness — the largest known planetary rings were Jupiter's gossamer rings and Saturn's E ring.

Astronomers have long suspected the presence of this ring, which orbits Saturn at a radius of about 8 million miles (13 million km) — 200 times the radius of the planet itself.

"There were hints that it could be there," said Douglas Hamilton of the University of Maryland, one of the astronomers who found the ring.

One such hint was the unusual coloring of Saturn's moon Iapetus, which had one dark side and one light side. Some astronomers suspected that the dark side, which looked suspiciously similar in composition to another of Saturn's satellite, Phoebe, was actually debris dust from Phoebe stuck to Iapetus' surface.

But astronomers haven't been able to detect it until now because, "this thing is just immense," Hamilton told SPACE.com. "If you look at just a small patch of it, you just see fuzziness."

Hamilton and his colleagues were finally able to see the behemoth ring with the infrared capability of the Spitzer Space Telescope. Spitzer was able to detect the sunlight reflected by the tiny dark black particles. The discovery is detailed in the Oct. 8 issue of the journal Nature.

The particles were likely created when asteroids, meteors or other bodies collided with Phoebe over the eons. While some of the particles are small enough to drift out of Saturn's gravitational grasp and into interplanetary space, others drift inwards toward the planet, where some get stuck to the leading hemisphere of Iapetus, which trawls through them. Periodic collisions replace the particles lost in these ways.

Interestingly, Phoebe and its associated dust ring travel in the opposite direction of Saturn's other rings and satellites.

The tiny particles are extremely diffuse, with only about 20 in every cubic kilometer of the ring, Hamilton said.

"If you were there, you wouldn't know you were in a ring," he said.

And because the other gas giants are known to have far-out, irregular satellites like Phoebe, it is likely that they also have similarly large, diffuse rings orbiting millions of kilometers out.

"I think this is the tip of the iceberg," Hamilton said."<

posted in Astronomy - 2 replies

Lunar Impact

Serge — Wed, 07 Oct 2009 04:21:37 GMT

Space Weather News for Oct. 6, 2009
http://spaceweather.com

This Friday morning, Oct 9th, at approximately 4:30 am PDT, NASA's LCROSS spacecraft and its Centaur booster rocket will plunge one after another into a shadowed crater near the Moon's south pole. The spectacular double-impact will be shown live on NASA TV from the point of view of the LCROSS spacecraft. Meanwhile, impact debris plumes emerging from the crater may be visible through backyard telescopes. North American sky watchers west of the Mississippi river are favored with darkness and good views of the Moon at the time of impact. Visit http://spaceweather.com for observing tips and full coverage.

posted in Astronomy - 15 replies

The Purpose of the Moon?

in-PHI-net — Fri, 02 Oct 2009 03:40:30 GMT

I am very curious about the moon. It amazes me that our moon takes so many hits and blasts from meteoroids and asteroids, but Earth is somewhat shielded and safe. Is there something in the moon (illuminated rocks/magnetic field?) that attracts these flying objects to itself, which in turn protects Earth? Is the moon a naturall guard against space debris for this planet? I understand that Jupiter protects us to some degree.

What is the purpose of the Moon?

posted in Astronomy - 22 replies

Proto-planet by Hubble

idea1407 — Thu, 08 Oct 2009 19:15:27 GMT

http://dsc.discovery.com/space/big-pic/hubble-pallas-asteroid-protoplanet.html

>"Oct. 8, 2009 -- A protoplanet is a planetary embryo, a baby planet undergoing accretion by smaller pieces of space rock in protoplanetary disks. Although the Solar System's bodies are fully evolved planets, dwarf planets and asteroids, there is a very exclusive group of large asteroids with a protoplanetary flavor.

This exclusive group just added another member.

In research using the Hubble Space Telescope, a team headed by UCLA scientists have deduced that an asteroid measuring 265 km (165 miles) in diameter is a protoplanet, joining asteroids 1 Ceres and 4 Vesta as only the third intact protoplanet. 2 Pallas is one of the largest asteroids in the asteroid belt (orbiting the sun at a distance of between 3.4 AU and 2.1 AU), accounting for 7 percent of the total mass of the entire belt.

This new 2 Pallas study (to be published in the Oct. 9 issue of Science) identified color variations and features in the asteroid's surface that can be linked to the asteroid's thermal evolution, indicating that this planetary embryo had the potential to grow. The researchers proposed that 2 Pallas formed from water-rich material and that internal alteration (i.e. the differentiation of elements common in the interior of planets) may have occurred.

In addition, analysis of an impact crater on the asteroid has indicated that 2 Pallas was hit by something large in the past, generating lots of debris. It is thought that this impact may have produced what are known as "Pallas family" objects that continue to orbit with the asteroid to this day."<

Click on link for pic

posted in Astronomy - 0 replies

NASA Refines Asteroid Apophis' Path Toward Earth

Serge — Wed, 07 Oct 2009 22:05:49 GMT

DC Agle 818-393-9011
Jet Propulsion Laboratory, Pasadena, Calif.
agle@jpl.nasa.gov

Dwayne Brown 202-358-1726
NASA Headquarters, Washington
dwayne.c.brown@nasa.gov

News release: 2009-151, Oct. 7, 2009

PASADENA, Calif. -- Using updated information, NASA scientists have recalculated the path of a large asteroid. The refined path indicates a significantly reduced likelihood of a hazardous encounter with Earth in 2036.

The Apophis asteroid is approximately the size of two-and-a-half football fields. The new data were documented by near-Earth object scientists Steve Chesley and Paul Chodas at NASA's Jet Propulsion Laboratory in Pasadena, Calif. They will present their updated findings at a meeting of the American Astronomical Society's Division for Planetary Sciences in Puerto Rico on Oct. 8.

"Apophis has been one of those celestial bodies that has captured the public's interest since it was discovered in 2004," said Chesley. "Updated computational techniques and newly available data indicate the probability of an Earth encounter on April 13, 2036, for Apophis has dropped from one-in-45,000 to about four-in-a million."

A majority of the data that enabled the updated orbit of Apophis came from observations Dave Tholen and collaborators at the University of Hawaii's Institute for Astronomy in Manoa made. Tholen pored over hundreds of previously unreleased images of the night sky made with the University of Hawaii's 2.2-meter (88-inch) telescope, located near the summit of Mauna Kea.

Tholen made improved measurements of the asteroid's position in the images, enabling him to provide Chesley and Chodas with new data sets more precise than previous measures for Apophis. Measurements from the Steward Observatory's 2.3 meter (90-inch) Bok telescope on Kitt Peak in Arizona and the Arecibo Observatory on the island of Puerto Rico also were used in Chesley's calculations.

The information provided a more accurate glimpse of Apophis' orbit well into the latter part of this century. Among the findings is another close encounter by the asteroid with Earth in 2068 with chance of impact currently at approximately three-in-a-million. As with earlier orbital estimates where Earth impacts in 2029 and 2036 could not initially be ruled out due to the need for additional data, it is expected that the 2068 encounter will diminish in probability as more information about Apophis is acquired.

Initially, Apophis was thought to have a 2.7 percent chance of impacting Earth in 2029. Additional observations of the asteriod ruled out any possibility of an impact in 2029. However, the asteroid is expected to make a record-setting -- but harmless -- close approach to Earth on Friday, April 13, 2029, when it comes no closer than 29,450 kilometers (18,300 miles) above Earth's surface.

"The refined orbital determination further reinforces that Apophis is an asteroid we can look to as an opportunity for exciting science and not something that should be feared," said Don Yeomans, manager of the Near-Earth Object Program Office at JPL. "The public can follow along as we continue to study Apophis and other near-Earth objects by visiting us on our AsteroidWatch Web site and by following us on the @AsteroidWatch Twitter feed."

The science of predicting asteroid orbits is based on a physical model of the solar system which includes the gravitational influence of the sun, moon, other planets and the three largest asteroids.

NASA detects and tracks asteroids and comets passing close to Earth using both ground and space-based telescopes. The Near-Earth Object Observations Program, commonly called "Spaceguard," discovers these objects, characterizes a subset of them and plots their orbits to determine if any could be potentially hazardous to our planet.

JPL manages the Near-Earth Object Program Office for NASA's Science Mission Directorate in Washington. JPL is a division of the California Institute of Technology in Pasadena. Cornell University, Ithaca, N.Y., operates the Arecibo Observatory under a cooperative agreement with the National Science Foundation in Arlington, Va.

For more information about asteroids and near-Earth objects, visit:

http://www.jpl.nasa.gov/asteroidwatch

For more information about NASA, visit: http://www.nasa.gov

- end -

posted in Astronomy - 1 reply

NASA Space Telescope Discovers Largest Ring Around Saturn

Serge — Wed, 07 Oct 2009 04:22:57 GMT

Whitney Clavin 818-354-4673
Jet Propulsion Laboratory, Pasadena, Calif.
whitney.clavin@jpl.nasa.gov

J.D. Harrington 202-358-5241
NASA Headquarters, Washington
j.d.harrington@nasa.gov

News release: 2009-150, Oct. 6, 2009

PASADENA, Calif. -- NASA's Spitzer Space Telescope has discovered an enormous ring around Saturn -- by far the largest of the giant planet's many rings.

The new belt lies at the far reaches of the Saturnian system, with an orbit tilted 27 degrees from the main ring plane. The bulk of its material starts about six million kilometers (3.7 million miles) away from the planet and extends outward roughly another 12 million kilometers (7.4 million miles). One of Saturn's farthest moons, Phoebe, circles within the newfound ring, and is likely the source of its material.

Saturn's newest halo is thick, too -- its vertical height is about 20 times the diameter of the planet. It would take about one billion Earths stacked together to fill the ring.

"This is one supersized ring," said Anne Verbiscer, an astronomer at the University of Virginia, Charlottesville. "If you could see the ring, it would span the width of two full moons' worth of sky, one on either side of Saturn." Verbiscer; Douglas Hamilton of the University of Maryland, College Park; and Michael Skrutskie, of the University of Virginia, Charlottesville, are authors of a paper about the discovery to be published online tomorrow by the journal Nature.

An artist's concept of the newfound ring is online at http://www.nasa.gov/mission_pages/spitzer/multimedia/spitzer-20091007a.html .

The ring itself is tenuous, made up of a thin array of ice and dust particles. Spitzer's infrared eyes were able to spot the glow of the band's cool dust. The telescope, launched in 2003, is currently 107 million kilometers (66 million miles) from Earth in orbit around the sun.

The discovery may help solve an age-old riddle of one of Saturn's moons. Iapetus has a strange appearance -- one side is bright and the other is really dark, in a pattern that resembles the yin-yang symbol. The astronomer Giovanni Cassini first spotted the moon in 1671, and years later figured out it has a dark side, now named Cassini Regio in his honor. A stunning picture of Iapetus taken by NASA's Cassini spacecraft is online at http://photojournal.jpl.nasa.gov/catalog/PIA08384 .

Saturn's newest addition could explain how Cassini Regio came to be. The ring is circling in the same direction as Phoebe, while Iapetus, the other rings and most of Saturn's moons are all going the opposite way. According to the scientists, some of the dark and dusty material from the outer ring moves inward toward Iapetus, slamming the icy moon like bugs on a windshield.

"Astronomers have long suspected that there is a connection between Saturn's outer moon Phoebe and the dark material on Iapetus," said Hamilton. "This new ring provides convincing evidence of that relationship."

Verbiscer and her colleagues used Spitzer's longer-wavelength infrared camera, called the multiband imaging photometer, to scan through a patch of sky far from Saturn and a bit inside Phoebe's orbit. The astronomers had a hunch that Phoebe might be circling around in a belt of dust kicked up from its minor collisions with comets -- a process similar to that around stars with dusty disks of planetary debris. Sure enough, when the scientists took a first look at their Spitzer data, a band of dust jumped out.

The ring would be difficult to see with visible-light telescopes. Its particles are diffuse and may even extend beyond the bulk of the ring material all the way in to Saturn and all the way out to interplanetary space. The relatively small numbers of particles in the ring wouldn't reflect much visible light, especially out at Saturn where sunlight is weak.

"The particles are so far apart that if you were to stand in the ring, you wouldn't even know it," said Verbiscer.

Spitzer was able to sense the glow of the cool dust, which is only about 80 Kelvin (minus 316 degrees Fahrenheit). Cool objects shine with infrared, or thermal radiation; for example, even a cup of ice cream is blazing with infrared light. "By focusing on the glow of the ring's cool dust, Spitzer made it easy to find," said Verbiscer.

These observations were made before Spitzer ran out of coolant in May and began its "warm" mission.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology, also in Pasadena. Caltech manages JPL for NASA. The multiband imaging photometer for Spitzer was built by Ball Aerospace Corporation, Boulder, Colo., and the University of Arizona, Tucson. Its principal investigator is George Rieke of the University of Arizona.

For additional images relating to the ring discovery and more information about Spitzer, visit http://www.spitzer.caltech.edu/spitzer and http://www.nasa.gov/spitzer .

- end -

posted in Astronomy - 0 replies

Globular Cluster Question

Freakshowcrow — Mon, 05 Oct 2009 15:49:53 GMT

Why are the majority of the stars in globular clusters really, really, really old?

Over 10 billion years old. Plus if they are that ancient why are they still "shining" (after accounting for distance in space = distance in the past of course.) today?

posted in Astronomy - 3 replies

Calling All Space Buffs!

Serge — Sat, 03 Oct 2009 19:26:13 GMT

Calling All Space Buffs!

Do you love space? Are you good about sharing your love of the stars with the public? If so, here's a chance to join a growing network of space enthusiasts who have volunteered as NASA Solar System Ambassadors.
Ambassadors are especially needed to represent Delaware and North Dakota.

The application period is being extended through Oct. 16. Ambassadors are U.S. citizens selected from all 50 states, plus Washington, D.C., and Puerto Rico, or U.S. citizens serving U.S. audiences abroad.
The program is one of the longest-running NASA volunteer outreach projects.

Each ambassador receives online training from JPL, and educational materials supplied by various space missions,
such as the next Mars rover--Curiosity. Curiosity will check to see whether Mars has been favorable for supporting microbial life and preserving evidence of life. The rover is scheduled to launch in October 2011.

You can apply to be a NASA Solar System Ambassador at: http://www.jpl.nasa.gov/events/ssa.cfm .

For more information on JPL's Solar System Ambassador Program, visit http://www2.jpl.nasa.gov/ambassador/index.html , or contact Kay Ferrari at ambassadors@jpl.nasa.gov or at 818-354-7581.

A calendar of events hosted by ambassadors is available at http://www2.jpl.nasa.gov/ambassador/events.html .

JPL is managed for NASA by the California Institute of Technology in Pasadena, Calif.

-end-

From: subscription email

posted in Astronomy - 0 replies

Mercury's Bright Spot

idea1407 — Thu, 01 Oct 2009 18:14:48 GMT

http://www.space.com/scienceastronomy/091001-mercury-bright-spot.html

>"Mercury's Mysterious Bright Spot Photographed Up Close
By Andrea Thompson
Senior Writer
posted: 01 October 2009
12:23 pm ET

During its most recent flyby of Mercury, NASA's MESSENGER spacecraft caught another glimpse of the innermost planet's mysterious bright spot.

The MESSENGER probe skimmed just 142 miles (228 km) above Mercury at its closest approach as it whipped around the planet during the flyby, the last of three designed to guide the spacecraft into orbit around the planet in 2011.

The $446 million probe snapped several new images of Mercury during the flyby, despite a minor data hiccup that delayed the downlink of some of the images.

One of the new images shows a bright spot on the planet's surface, a feature that scientists cannot yet explain.

The new view was the third of the spot, which was first seen in telescopic images of Mercury obtained from Earth by astronomer Ronald Dantowitz. The second view was obtained by the MESSENGER Narrow Angle Camera during the spacecraft's second Mercury flyby Oct. 6, 2008. At that time, the bright feature was just on the planet's limb (edge) as seen from MESSENGER.

Surprisingly, at the center of the bright halo is an irregular depression, which may have formed through volcanic processes. The object will be further investigated when MESSENGER arrives at its final orbit around Mercury.

In the new images were also pictures of impact basins, including a double-ring impact basin, with another large impact crater on its south-southwestern side. Double-ring basins are formed when a large meteoroid strikes the surface of a rocky planet.

The floor within the inner or peak ring appears to be smoother than the floor between the peak ring and the outer rim, possibly the result of lava flows that partially flooded the basin some time after impact.

Some of these craters are relatively fresh, formed by more recent impacts. On Mercury, like the Earth's moon, even ancient impact craters can be preserved on the surface because there is no atmosphere to cause erosion and no plate tectonics to recycle the rock, as there are on Earth.

One set of impact craters even coincidentally resemble a paw print.

MESSENGER was also able to image some of the same terrain as it did in its second flyby, but this time with slightly different lightning conditions. Different angles of sunlight can better show the topography of the planet's surface.

MESSENGER made its closest approach to Mercury at about 5:55 p.m. EDT (2155 GMT) when it sped by at about 12,000 mph (19,312 kph). The probe then flew behind Mercury, passing out of communications with Earth for about an hour before restoring contact.

The spacecraft is the first probe to visit Mercury since NASA's Mariner 10 mission in the mid-1970s.

NASA launched MESSENGER - short for MErcury Surface, Space ENvironment, GEochemistry, and Ranging - in 2004. The probe swung past Earth once and Venus twice before beginning its three Mercury flybys."<

posted in Astronomy - 0 replies

Star formation and magnetism

idea1407 — Wed, 30 Sep 2009 14:36:22 GMT

http://www.space.com/scienceastronomy/090929-star-formation.html

>"Magnetic Fields Guide Star Birth

By SPACE.com Staff

posted: 29 September 2009
08:52 am ET

The picture of star formation just got a little more complicated: Cosmic magnetic fields, which can channel condensing interstellar gas, play a more important role in the birth of stars that previously thought, a new study suggests.

The simplified story of stellar birth involves giant clouds of gas and dust collapsing inward due to gravity, growing denser and hotter until nuclear fusion ignites a newborn star.

But in reality, there's much more to the story: When a molecular cloud collapses, only a small fraction of the cloud's material forms stars, and scientists haven't been sure why that is.

Since gravity favors star formation because it draws material together, some other force must be hindering the process, scientists reason. The two leading candidates are turbulence and magnetic fields.

Magnetic fields (produced by moving electrical charges and present around stars and most planets, including Earth) channel flowing gas, making it hard to draw the gas in from all directions. Turbulence stirs the gas and induces and outward pressure that counteracts gravity.

"The relative importance of magnetic fields versus turbulence is a matter of much debate," said astronomer Hua-bai Li of the Harvard-Smithsonian Center for Astrophysics. "Our findings serve as the first observational constraint on this issue."

Li and his team studied 25 dense patches, or cloud cores, each one about a light-year in size. The cores, which act as seeds from which stars form, were located within molecular clouds as much as 6,500 light-years from Earth. (A light-year is the distance light travels in a year, or 6 trillion miles.)

The researchers studied polarized light, which has electric and magnetic components that are aligned in specific directions. From the polarization, they measured the magnetic fields within each cloud core and compared them to the fields in the surrounding, tenuous nebula.

The magnetic fields tended to line up in the same direction, even though the relative size scales (1 light-year cores versus 1,000 light-year nebulas) and densities were different by orders of magnitude. Since turbulence would tend to churn the nebula and mix up magnetic field directions, their findings show that magnetic fields dominate turbulence in influencing star birth.

"Our result shows that molecular cloud cores located near each other are connected not only by gravity but also by magnetic fields," Li said. "This shows that computer simulations modeling star formation must take strong magnetic fields into account."

The study will be detailed in an upcoming issue of the Astrophysical Journal."<

posted in Astronomy - 5 replies

How we know what the objects in the universe are made of.

Serge — Tue, 29 Sep 2009 20:55:21 GMT

Generally, the light we see is composed of a mixture of wavelengths. White light is composed of red, green, yellow, and blue photons. We can separate light into its component wavelengths by using a dispersing element, either a prism or a diffraction grating. Once the light is dispersed, it forms a spectrum. A rainbow is an example of a spectrum (the dispersing elements are water droplets which act as prisms). The plural of "spectrum" is "spectra".

There are 2 basic kinds of spectra:

Continuous spectra, like a rainbow.
Line spectra. The light is concentrated into specific colors or wavelengths.

Spectra are a powerful tool for studying astronomical objects.

A diffraction grating consists usually of thousands of narrow, closely spaced parallel slits (or grooves). These grooves selectively filter the light, spreading it into patches of specific wavelengths, so that the resulting image beyond the grating contains the color bars representing the signature pattern of the source of light. Elements which are gaseous can be identified by shining a light through them. As long as the light source has a continuous spectrum, and the gas is cooler than the source, then the image created by the diffraction grating identifies the gas by its absorption lines.

Elements that are liquid or solid can be identified by examining the reflected light from a source with a continuous spectrum...

Continue - http://hea-www.harvard.edu/~efortin/thesis/html/Spectroscopy.shtml ; with awesome visualisations.

posted in Astronomy - 1 reply

Radar Map of Buried Mars Layers Matches Climate Cycles

Serge — Sun, 27 Sep 2009 23:39:26 GMT

Guy Webster 818-354-6278
Jet Propulsion Laboratory, Pasadena, Calif.
guy.webster@jpl.nasa.gov

Maria Martinez 210-522-3305
Southwest Research Institute, San Antonio, Texas
maria.martinez@swri.org

Dwayne Brown 202-358-1726
NASA Headquarters, Washington
dwayne.c.brown@nasa.gov

News release: 2009-144, September 22, 2009

PASADENA, Calif. -- New, three-dimensional imaging of Martian north-polar ice layers by a radar instrument on NASA's Mars Reconnaissance Orbiter is consistent with theoretical models of Martian climate swings during the past few million years.

Alignment of the layering patterns with the modeled climate cycles provides insight about how the layers accumulated. These ice-rich, layered deposits cover an area one-third larger than Texas and form a stack up to 2 kilometers (1.2 miles) thick atop a basal deposit with additional ice.

"Contrast in electrical properties between layers is what provides the reflectivity we observe with the radar," said Nathaniel Putzig of Southwest Research Institute, Boulder, Colo., a member of the science team for the Shallow Radar instrument on the orbiter. "The pattern of reflectivity tells us about the pattern of material variations within the layers."

Earlier radar observations indicated that the Martian north-polar layered deposits are mostly ice. Radar contrasts between different layers in the deposits are interpreted as differences in the concentration of rock material, in the form of dust, mixed with the ice. These deposits on Mars hold about one-third as much water as Earth's Greenland ice sheet.

Putzig and nine co-authors report findings from 358 radar observations in a paper accepted for publication by the journal Icarus and currently available online.

Their radar results provide a cross-sectional view of the north-polar layered deposits of Mars, showing that high-reflectivity zones, with multiple contrasting layers, alternate with more-homogenous zones of lower reflectivity. Patterns of how these two types of zones alternate can be correlated to models of how changes in Mars' tilt on its axis have produced changes in the planet's climate in the past 4 million years or so, but only if some possibilities for how the layers form are ruled out.

"We're not doing the climate modeling here; we are comparing others' modeling results to what we observe with the radar, and using that comparison to constrain the possible explanations for how the layers form," Putzig said.

The most recent 300,000 years of Martian history are a period of less dramatic swings in the planet's tilt than during the preceding 600,000 years. Since the top zone of the north-polar layered deposits -- the most recently deposited portion -- is strongly radar-reflective, the researchers propose that such sections of high-contrast layering correspond to periods of relatively small swings in the planet's tilt.

They also propose a mechanism for how those contrasting layers would form. The observed pattern does not fit well with an earlier interpretation that the dustier layers in those zones are formed during high-tilt periods when sunshine on the polar region sublimates some of the top layer's ice and concentrates the dust left behind. Rather, it fits an alternative interpretation that the dustier layers are simply deposited during periods when the atmosphere is dustier.

The new radar mapping of the extent and depth of five stacked units in the north-polar layered deposits reveals that the geographical center of ice deposition probably shifted by 400 kilometers (250 miles) or more at least once during the past few million years.

"The radar has been giving us spectacular results," said Jeffrey Plaut of NASA's Jet Propulsion Laboratory, Pasadena, Calif., a co-author of the paper. "We have mapped continuous underground layers in three dimensions across a vast area."

The Italian Space Agency operates the Shallow Radar instrument, which it provided for NASA's Mars Reconnaissance Orbiter. The orbiter has been studying Mars with six advanced instruments since 2006. It has returned more data from the planet than all other past and current missions to Mars combined. For more information about the mission, visit: http://www.nasa.gov/mro .

JPL, a division of the California Institute of Technology, Pasadena, manages the Mars Reconnaissance Orbiter for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, is the prime contractor for the project and built the spacecraft.

- end -

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Mars: meterorites expose water after impact

idea1407 — Sat, 26 Sep 2009 19:40:58 GMT

http://www.youtube.com/watch?v=B7cmPU2NLJ4

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Water molecules on Moon

idea1407 — Thu, 24 Sep 2009 19:35:24 GMT

http://www.nasa.gov/home/hqnews/2009/sep/HQ_09-222_Moon_Water_Molecules.html

>"RELEASE : 09-222

NASA Instruments Reveal Water Molecules on Lunar Surface

WASHINGTON -- NASA scientists have discovered water molecules in the polar regions of the moon. Instruments aboard three separate spacecraft revealed water molecules in amounts that are greater than predicted, but still relatively small. Hydroxyl, a molecule consisting of one oxygen atom and one hydrogen atom, also was found in the lunar soil. The findings were published in Thursday's edition of the journal Science.

NASA's Moon Mineralogy Mapper, or M3, instrument reported the observations. M3 was carried into space on Oct. 22, 2008, aboard the Indian Space Research Organization's Chandrayaan-1 spacecraft. Data from the Visual and Infrared Mapping Spectrometer, or VIMS, on NASA's Cassini spacecraft and the High-Resolution Infrared Imaging Spectrometer on NASA's EPOXI spacecraft contributed to confirmation of the finding. The spacecraft imaging spectrometers made it possible to map lunar water more effectively than ever before.

The confirmation of elevated water molecules and hydroxyl at these concentrations in the moon's polar regions raises new questions about its origin and effect on the mineralogy of the moon. Answers to these questions will be studied and debated for years to come.

"Water ice on the moon has been something of a holy grail for lunar scientists for a very long time," said Jim Green, director of the Planetary Science Division at NASA Headquarters in Washington. "This surprising finding has come about through the ingenuity, perseverance and international cooperation between NASA and the India Space Research Organization."

From its perch in lunar orbit, M3's state-of-the-art spectrometer measured light reflecting off the moon's surface at infrared wavelengths, splitting the spectral colors of the lunar surface into small enough bits to reveal a new level of detail in surface composition. When the M3 science team analyzed data from the instrument, they found the wavelengths of light being absorbed were consistent with the absorption patterns for water molecules and hydroxyl.

"For silicate bodies, such features are typically attributed to water and hydroxyl-bearing materials," said Carle Pieters, M3's principal investigator from Brown University. "When we say 'water on the moon,' we are not talking about lakes, oceans or even puddles. Water on the moon means molecules of water and hydroxyl that interact with molecules of rock and dust specifically in the top millimeters of the moon's surface. "

The M3 team found water molecules and hydroxyl at diverse areas of the sunlit region of the moon's surface, but the water signature appeared stronger at the moon's higher latitudes. Water molecules and hydroxyl previously were suspected in data from a Cassini flyby of the moon in 1999, but the findings were not published until now.

"The data from Cassini's VIMS instrument and M3 closely agree," said Roger Clark, a U.S. Geological Survey scientist in Denver and member of both the VIMS and M3 teams. "We see both water and hydroxyl. While the abundances are not precisely known, as much as 1,000 water molecule parts-per-million could be in the lunar soil. To put that into perspective, if you harvested one ton of the top layer of the moon's surface, you could get as much as 32 ounces of water."

For additional confirmation, scientists turned to the EPOXI mission while it was flying past the moon in June 2009 on its way to a November 2010 encounter with comet Hartley 2. The spacecraft not only confirmed the VIMS and M3 findings, but also expanded on them.

"With our extended spectral range and views over the north pole, we were able to explore the distribution of both water and hydroxyl as a function of temperature, latitude, composition, and time of day," said Jessica Sunshine of the University of Maryland. Sunshine is EPOXI's deputy principal investigator and a scientist on the M3 team. "Our analysis unequivocally confirms the presence of these molecules on the moon's surface and reveals that the entire surface appears to be hydrated during at least some portion of the lunar day."

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the M3 instrument, Cassini mission and EPOXI spacecraft for NASA's Science Mission Directorate in Washington. The Indian Space Research Organization built, launched and operated the Chandrayaan-1 spacecraft."<

posted in Astronomy - 2 replies

NASA's Spitzer Spots Clump of Swirling Planetary Material

Serge — Thu, 24 Sep 2009 22:38:53 GMT

Whitney Clavin 818-354-4673
Jet Propulsion Laboratory, Pasadena, Calif.
whitney.clavin@jpl.nasa.gov

News release: 2009-146, Sept. 23, 2009

PASADENA, Calif. -- Astronomers have witnessed odd behavior around a young star. Something, perhaps another star or a planet, appears to be pushing a clump of planet-forming material around. The observations, made with NASA's Spitzer Space Telescope, offer a rare look into the early stages of planet formation.

Planets form out of swirling disks of gas and dust. Spitzer observed infrared light coming from one such disk around a young star, called LRLL 31, over a period of five months. To the astronomers' surprise, the light varied in unexpected ways, and in as little time as one week. Planets take millions of years to form, so it's rare to see anything change on time scales we humans can perceive.

One possible explanation is that a close companion to the star -- either a star or a developing planet -- could be shoving planet-forming material together, causing its thickness to vary as it spins around the star.

"We don't know if planets have formed, or will form, but we are gaining a better understanding of the properties and dynamics of the fine dust that could either become, or indirectly shape, a planet," said James Muzerolle of the Space Telescope Science Institute, Baltimore, Md. Muzerolle is first author of a paper accepted for publication in the Astrophysical Journal Letters. "This is a unique, real-time glimpse into the lengthy process of building planets."

One theory of planet formation suggests that planets start out as dusty grains swirling around a star in a disk. They slowly bulk up in size, collecting more and more mass like sticky snow. As the planets get bigger and bigger, they carve out gaps in the dust, until a so-called transitional disk takes shape with a large doughnut-like hole at its center. Over time, this disk fades and a new type of disk emerges, made up of debris from collisions between planets, asteroids and comets. Ultimately, a more settled, mature solar system like our own forms.

Before Spitzer was launched in 2003, only a few transitional disks with gaps or holes were known. With Spitzer's improved infrared vision, dozens have now been found. The space telescope sensed the warm glow of the disks and indirectly mapped out their structures.

Muzerolle and his team set out to study a family of young stars, many with known transitional disks. The stars are about two to three million years old and about 1,000 light-years away, in the IC 348 star-forming region of the constellation Perseus. A few of the stars showed surprising hints of variations. The astronomers followed up on one, LRLL 31, studying the star over five months with all three of Spitzer's instruments.

The observations showed that light from the inner region of the star's disk changes every few weeks, and, in one instance, in only one week. "Transition disks are rare enough, so to see one with this type of variability is really exciting," said co-author Kevin Flaherty of the University of Arizona, Tucson.

Both the intensity and the wavelength of infrared light varied over time. For instance, when the amount of light seen at shorter wavelengths went up, the brightness at longer wavelengths went down, and vice versa.

Muzerolle and his team say that a companion to the star, circling in a gap in the system's disk, could explain the data. "A companion in the gap of an almost edge-on disk would periodically change the height of the inner disk rim as it circles around the star: a higher rim would emit more light at shorter wavelengths because it is larger and hot, but at the same time, the high rim would shadow the cool material of the outer disk, causing a decrease in the longer-wavelength light. A low rim would do the opposite. This is exactly what we observe in our data," said Elise Furlan, a co-author from NASA's Jet Propulsion Laboratory, Pasadena, Calif.

The companion would have to be close in order to move the material around so fast -- about one-tenth the distance between Earth and the sun.

The astronomers plan to follow up with ground-based telescopes to see if a companion is tugging on the star hard enough to be perceived. Spitzer will also observe the system again in its "warm" mission to see if the changes are periodic, as would be expected with an orbiting companion. Spitzer ran out of coolant in May of this year, and is now operating at a slightly warmer temperature with two infrared channels still functioning.

"For astronomers, watching anything in real-time is exciting," said Muzerolle. "It's like we're biologists getting to watch cells grow in a petri dish, only our specimen is light-years away."

Other authors are Zoltan Balog, Max Planck Institute for Astronomy, Germany; Paul S. Smith and George Rieke, University of Arizona; Lori Allen, National Optical Astronomy Observatory, Tucson; Nuria Calvet, University of Michigan, Ann Arbor; Paola D'Alessio, National Autonomous University of Mexico; S. Thomas Megeath, University of Toledo, Ohio; August Muench, Harvard-Smithsonian Center for Astrophysics, Cambridge; William H. Sherry, National Solar Observatory, Tucson.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology, also in Pasadena. Caltech manages JPL for NASA. For more information about Spitzer, visit http://www.spitzer.caltech.edu/spitzer and http://www.nasa.gov/spitzer .

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NASA Spacecraft Sees Ice on Mars Exposed by Meteor Impacts

Serge — Thu, 24 Sep 2009 22:33:30 GMT

Guy Webster 818-354-6278
Jet Propulsion Laboratory, Pasadena, Calif.
guy.webster@jpl.nasa.gov

Dwayne Brown 202-358-1726
NASA Headquarters, Washington
dwayne.c.brown@nasa.gov

News release: 2009-148, Sept. 24, 2009

PASADENA, Calif. -- NASA's Mars Reconnaissance Orbiter has revealed frozen water hiding just below the surface of mid-latitude Mars. The spacecraft's observations were obtained from orbit after meteorites excavated fresh craters on the Red Planet.

Scientists controlling instruments on the orbiter found bright ice exposed at five Martian sites with new craters that range in depth from approximately half a meter to 2.5 meters (1.5 feet to 8 feet). The craters did not exist in earlier images of the same sites. Some of the craters show a thin layer of bright ice atop darker underlying material. The bright patches darkened in the weeks following initial observations, as the freshly exposed ice vaporized into the thin Martian atmosphere. One of the new craters had a bright patch of material large enough for one of the orbiter's instruments to confirm it is water-ice.

The finds indicate water-ice occurs beneath Mars' surface halfway between the north pole and the equator, a lower latitude than expected in the Martian climate.

"This ice is a relic of a more humid climate from perhaps just several thousand years ago," said Shane Byrne of the University of Arizona, Tucson.

Byrne is a member of the team operating the orbiter's High Resolution Imaging Science Experiment, or HiRISE camera, which captured the unprecedented images. Byrne and 17 co-authors report the findings in the Sept. 25 edition of the journal Science.

"We now know we can use new impact sites as probes to look for ice in the shallow subsurface," said Megan Kennedy of Malin Space Science Systems in San Diego, a co-author of the paper and member of the team operating the orbiter's Context Camera.

During a typical week, the Context Camera returns more than 200 images of Mars that cover a total area greater than California. The camera team examines each image, sometimes finding dark spots that fresh, small craters make in terrain covered with dust. Checking earlier photos of the same areas can confirm a feature is new. The team has found more than 100 fresh impact sites, mostly closer to the equator than the ones that revealed ice.

An image from the camera on Aug. 10, 2008, showed apparent cratering that occurred after an image of the same ground was taken 67 days earlier. The opportunity to study such a fresh impact site prompted a look by the orbiter's higher resolution camera on Sept. 12, 2009, confirming a cluster of small craters.

"Something unusual jumped out," Byrne said. "We observed bright material at the bottoms of the craters with a very distinct color. It looked a lot like ice."

The bright material at that site did not cover enough area for a spectrometer instrument on the orbiter to determine its composition. However, a Sept. 18, 2008, image of a different mid-latitude site showed a crater that had not existed eight months earlier. This crater had a larger area of bright material.

"We were excited about it, so we did a quick-turnaround observation," said co-author Kim Seelos of Johns Hopkins University Applied Physics Laboratory in Laurel, Md. "Everyone thought it was water-ice, but it was important to get the spectrum for confirmation."

Mars Reconnaissance Orbiter Project Scientist Rich Zurek, of NASA's Jet Propulsion Laboratory, Pasadena, Calif., said, "This mission is designed to facilitate coordination and quick response by the science teams. That makes it possible to detect and understand rapidly changing features."

The ice exposed by fresh impacts suggests that NASA's Viking Lander 2, digging into mid-latitude Mars in 1976, might have struck ice if it had dug 10 centimeters (4 inches) deeper. The Viking 2 mission, which consisted of an orbiter and a lander, launched in September 1975 and became one of the first two space probes to land successfully on the Martian surface. The Viking 1 and 2 landers characterized the structure and composition of the atmosphere and surface. They also conducted on-the-spot biological tests for life on another planet.

NASA's Jet Propulsion Laboratory in Pasadena manages the Mars Reconnaissance Orbiter for NASA's Science Mission Directorate in Washington. Lockheed Martin Space Systems in Denver built the spacecraft. The Context Camera was built and is operated by Malin Space Science Systems. The University of Arizona operates the HiRISE camera, which Ball Aerospace & Technologies Corp., in Boulder, Colo., built. The Johns Hopkins University Applied Physics Laboratory led the effort to build the Compact Reconnaissance Imaging Spectrometer and operates it in coordination with an international team of researchers.

To view images of the craters and learn more about the Mars Reconnaissance Orbiter, visit http://www.nasa.gov/mro or http://marsprogram.jpl.nasa.gov/mro/ .

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Teacher Training Opportunity: Goldstone Apple Valley Radio Telescope Program

Serge — Thu, 24 Sep 2009 03:11:02 GMT

The Lewis Center for Educational Research (LCER) announces an opportunity for K - 12 teachers to participate in our rather unique program. The Goldstone Apple Valley Radio Telescope Program (GAVRT) is an education partnership involving NASA, the Jet Propulsion Laboratory (JPL) and LCER. It is a K-12 project using radio astronomy to provide an opportunity for students to experience real science and to learn that science is an ongoing process and actual discovery is possible.
Using their classroom computer, 32,000 students have taken control of a 34-meter, 500-ton, 9-story-high radio telescope located at NASA's Deep Space Network at Goldstone, CA. We currently have trained 473 teachers at 283 schools in 37 states across the United States and at American schools in 14 countries and 3 U.S. territories.

What's in it for the kids? They learn how to gather data, understand what the data mean and how to follow through with analysis. Students and teachers team with scientists to conduct cutting-edge research leading to discovery. GAVRT excites students while accomplishing educational and scientific objectives.

We are excited to include Radio JOVE with our training in 2010. Radio JOVE is a NASA education program: Solar and planetary radio astronomy for schools. It is a hands-on educational activity that brings the radio sounds of the sun, Jupiter, the Milky Way galaxy and terrestrial radio noise to students, teachers and the general public. We target grade levels 6 - 14 to:

• Build a simple radio telescope kit
• Speak with professional radio astronomers
• Make scientific observations
• Interact with radio observatories in real-time

One of our main goals is to motivate students to learn about science by participating in a scientific activity, making measurements, acquiring and analyzing data, and sharing and discussing their results with other observers. For further information, see http://radiojove.gsfc.nasa.gov or call (301) 286-9790 or (615) 898-5946.

Teachers need to attend a 5-day class in order to take this program back to their students. Teachers interested in participating are invited to apply online at this time at http://www.lewiscenter.org/gavrt/opportunities.php. We are conducting a 5-day teacher training class at the Lewis Center on March 8 - 12, July 19 - 23, and October 25 - 29, 2010, at our facility in Apple Valley, CA. Please check our Web site periodically for calendar updates. We strongly recommend at least two teachers attend the training from your school, or area. While this is not a requirement, it will definitely serve to help in program support once back in the classroom. The cost of the 5-day class is $745. For questions, e-mail gavrt-info@lcer.org or call (760) 946-5414 X234.

More information about GAVRT can be found at http://www.lewiscenter.org/gavrt/ .

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posted in Astronomy - 1 reply

Saturn rings with mountains

idea1407 — Tue, 22 Sep 2009 08:44:42 GMT

http://www.space.com/scienceastronomy/090921-new-saturn-ring-images.html

>"Surprising, Huge Peaks Discovered in Saturn's Rings
By SPACE.com Staff

posted: 21 September 2009
06:49 pm ET

Stunning new views of Saturn from a NASA spacecraft have revealed odd formations in the planet's trademark rings, including ripples as tall as the Rocky Mountains.

The new images taken by NASA's Cassini spacecraft show that Saturn's icy rings - once thought to be relatively thin - can be miles thick in some points and include weird, bright streaks from clouds kicked up by the cosmic clash between ring particles and interloping space debris.

"It's like putting on 3-D glasses and seeing the third dimension for the first time," said Bob Pappalardo, Cassini's project scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif., in a statement. "This is among the most important events Cassini has shown us."

Cassini recorded the new images of Saturn in the week surrounding the planet's Aug. 11 equinox, a time when its bright bands of rings are edge on to the sun and nearly invisible as seen from Earth.

The rare sight only occurs twice during Saturn's long orbit, which takes nearly 30 years to complete. Earth also has two equinoxes a year (vernal and autumnal), with the autumnal equinox to occur Tuesday.

Saturn's rings are made up of individual chunks of ice that reach out nearly 85,000 miles (140,000 km) from the center of the planet. In some spots they are only 30 feet (about 10 meters) thick, while others can reach towering heights, the new images revealed.

The unique lighting conditions brought on by Saturn's equinox and the sun illuminated the odd ripples and bumps among the planet's rings, which Cassini spied with its camera eyes. The staggering heights of some formations could be discerned by the shadows they cast, researchers said.

"We thought the plane of the rings was no taller than two stories of a modern-day building and instead we've come across walls more than 2 miles [3 kilometers] high," said Cassini imaging team leader Carolyn Porco at the Space Science Institute in Boulder, Colo. "Isn't that the most outrageous thing you could imagine? It truly is like something out of science fiction."

One ripple rises nearly 2 1/2 miles (4 km) above the plane of Saturn's rings. The big blip is caused by the gravitational tug of the planet's moon Daphnis. It is the highest peak among the rings, mission managers said.

Scientists estimate that there are about 35 trillion-trillion tons of ice, dust and rock locked up in Saturn's rings. Cassini has been studying Saturn and its rings since it arrived at the planet in 2004 and is currently in the middle of an extended mission to observe the gas giant's equinox period.

"To understand what we are seeing will take more time, but the images and data will help develop a more complete understanding of how old the rings might be and how they are evolving," said Linda Spilker, Cassini's deputy project scientist at JPL."<

posted in Astronomy - 0 replies

In Search of Dark Asteroids (and Other Sneaky Things)

Serge — Sat, 19 Sep 2009 01:42:27 GMT

Feature
September 18, 2009

Ninjas knew how to be stealthy: Be dark. Emit very little light. Move in the shadows between bright places.

In modern warfare, though, ninjas would be sitting ducks. Their black clothes may be hard to see at night with the naked eye, but their warm bodies would be clearly visible to a soldier wearing infrared goggles.

To hunt for the "ninjas" of the cosmos -- dim objects that lurk in the vast dark spaces between planets and stars -- scientists are building by far the most sensitive set of wide-angle infrared goggles ever, a space telescope called the Wide-field Infrared Survey Explorer, or WISE.

WISE will scan the entire sky at infrared wavelengths, creating the most comprehensive catalog yet of dark and dim objects in the cosmos: vast dust clouds, brown dwarf stars, asteroids -- even large, nearby asteroids that might pose a threat to Earth.

Surveys of nearby asteroids based on visible-light telescopes could be skewed toward asteroids with more-reflective surfaces. "If there's a significant population of asteroids nearby that are very dark, they will have been missed by these previous surveys," says Edward Wright, principal investigator for the mission and a physicist at UCLA.

The full-sky infrared map produced by WISE will reveal even these darker asteroids, mapping the locations and sizes of roughly 200,000 asteroids and giving scientists a clearer idea of how many large and potentially dangerous asteroids are nearby. WISE will also help answer questions about the formation of stars and the evolution and structure of galaxies, including our own Milky Way galaxy.

And the discoveries won't likely stop there.

"When you look at the sky with new sensitivity and a new wavelength band, like WISE is going to do, you're going to find new things that you didn't know were out there," Wright says.

Stars emit visible light in part because they're so hot. But cooler objects like asteroids emit light too, just at longer, infrared wavelengths that are invisible to the unaided eye. In fact, any object warmer than absolute zero will emit at least some infrared light.

Unfortunately, this fact makes building an infrared telescope rather difficult. Without a coolant, the telescope itself would glow in infrared light just like as other warm objects do. It would be like building a normal, visible-light telescope out of Times Square billboard lights: The telescope would be blinded by its own glow.

To solve this problem, WISE will cool its components to about 15 degrees Celsius above absolute zero (minus 258 degrees Celsius, or minus 433 degrees Fahrenheit) using a block of solid hydrogen. Mission scientists chose solid hydrogen over liquid helium, which is often used in research for cooling materials to near absolute zero, because a smaller volume of solid hydrogen can do the job. "The cooling power is much higher for hydrogen than for helium," Wright explains. When launching a telescope into space, being smaller and lighter saves money.

Previous space telescopes such as the Infrared Astronomical Satellite have mapped the sky at infrared wavelengths before, but WISE will be hundreds of times more sensitive. While other missions could only see diffuse sources of infrared light such as large dust clouds, WISE will be able to see asteroids and other point sources.

After it launches into orbit as early as this December, WISE will spend six months mapping the sky, during which it will download its data to ground stations four times each day. Analyzing that data should give scientists some new insights into the cosmos.

For example, one theory posits that most of the stars in the universe were formed in the press of colliding galaxies. When galaxies collide, interstellar clouds of gas and dust smash together, compressing the clouds and starting a self-perpetuating cycle of gravitational collapse. The result is a flurry of star birth. Newborn stars are usually concealed by the dusty clouds in which they are born. Ordinary light cannot escape, but infrared light can.

WISE will be able to detect infrared emissions from the most active star-forming regions. This will help scientists know how rapidly stars are formed during galactic collisions, which could indicate how many of the universe's stars were formed this way.

WISE will also target dim "failed stars" called brown dwarfs that outnumber ordinary stars by a wide margin. Mapping brown dwarfs in the Milky Way may reveal much about the structure and evolution of our own galaxy.

And this could be just the beginning of the discoveries scientists make once WISE puts the spotlight on stealthy denizens of the dark.

From material at Science@NASA

Media contact:
Whitney Clavin/ Jet Propulsion Laboratory
818-354-4673
whitney.clavin@jpl.nasa.gov

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First Rocky World outside our solar system detected

idea1407 — Wed, 16 Sep 2009 15:28:40 GMT

http://www.space.com/scienceastronomy/090916-rocky-exoplanet.html

>"First Rocky World Confirmed Around Another Star
By Clara Moskowitz
Staff Writer
posted: 16 September 2009
08:43 am ET

One of the smallest exoplanets yet discovered has just been confirmed as a rocky world, scientists announced.

The planet, called CoRoT-7b, is the first planet beyond our solar system with a proven density similar to Earth's, astronomers say. Most known exoplanets are large gas giants like Jupiter.

"We have indications that other exoplanets could be rocky, but it's the first time that the density of such a planet has been measured," said study team member Claire Moutou of the Laboratoire d'Astrophysique de Marseille in France. "We are really sure it's rocky."

Though its terrestrial surface renders CoRoT-7b more similar to Earth than many other exoplanets are, it's still a far cry from a familiar setting. The planet orbits extremely close to its star – about 1.6 million miles (2.5 million km), or 23 times closer than Mercury is to the sun. At this range, the planet's surface temperatures are scorching, with highs above 2,000 degrees Fahrenheit (1,000 degrees Celsius) on the star-facing side.

CoRoT-7b's close proximity to its star means that the planet is likely to be tidally locked, with one side always facing its sun and the other side always in darkness.

"Probably the day side is very hot and is pure lava, boiling, and the other side probably is very cold, and it could be rocky with some mountains," Moutou told SPACE.com. "It's not possible that there is liquid water."

Crowded universe

CoRoT-7b was discovered in February 2009 by the CoRoT space telescope, a European collaboration. The tiny planet was discovered orbiting a star slightly smaller and cooler than our sun, about 500 light-years away. As the planet passed in front of its star, it eclipsed a small portion of the star's light, causing a dip in brightness.

This dip was enough to tell that a planet existed, and to estimate the planet's distance from its host star and its radius, which is about 80 percent larger than Earth's. But to learn its density, which would reveal whether it is a rocky or gas planet, requires a precise measurement of the parent star's velocity, which is slightly warped by the planet's small mass.

To make this measurement astronomers used the High Accuracy Radial velocity Planet Searcher (HARPS) spectrograph on the European Southern Observatory's 3.6-meter telescope at La Silla Observatory in Chile. The new data revealed that CoRoT-7b has a mass about five times that of Earth, making it one of the lightest exoplanets yet found.

With the planet's mass and radius, the researchers calculated its density (about 4.7 grams per cubic centimeter), which placed it in firm rocky territory.

"This is the first proof of the detection of a rocky planet," planet-formation theorist Alan Boss of the Carnegie Institution of Washington told SPACE.com.

"It shows that rocky planets really are commonplace," said Boss, who was not involved in the new research. "The estimates are that about 30 percent of sun-like stars have these hot and warm super-Earths, and now that we know the density of one of them, it is easy to make the claim that most of the rest of them are probably rocky too. The evidence is becoming overwhelming that we live in a crowded universe.""<

posted in Astronomy - 7 replies

Comet to many comets

idea1407 — Wed, 16 Sep 2009 17:14:00 GMT

http://www.space.com/scienceastronomy/090915-mini-comets.html

>"Comet Outburst Spawns Mini-Comets
By SPACE.com Staff

posted: 15 September 2009
08:43 pm ET

A comet recently spewed out a cluster of mini comets in a huge outburst that was the largest ever witnessed by astronomers.

A team of researchers began observing the comet 17P/Holmes in October 2007, after it was reported that the object, about 2.2 miles wide (3.6 km wide), had brightened by a million times in less than a day.

UCLA researcher Rachel Stevenson and colleagues noted multiple fragments flying rapidly away from the comet's nucleus. They continued observing for several weeks after the outburst using the Canada-France-Hawaii Telescope in Hawaii and watched as the dust cloud ejected by the comet grew to be larger than the sun.

The astronomers examined a sequence of images taken over nine nights using a digital filter that enhances small features. They found numerous tiny objects that moved away from the nucleus at speeds of up to 280 mph (125 meters per second). These objects were too bright to simply be bare rocks, but instead were more like mini comets, creating their own dust clouds as ice on their surfaces sublimated directly to vapor.

"Initially we thought this comet was unique simply because of the scale of the outburst," Stevenson said. "But we soon realized that the aftermath of the outburst showed unusual features, such as these fast-moving fragments, that have not been detected around other comets."

Although the outburst was impressive in the telescope images, it wasn't visible to the naked eye.

Scientists aren't sure of the exact cause of the outburst. Possibly, pressure inside the comet built up as it moved closer to the sun, until eventually part of the surface broke away, releasing a huge cloud of dust and gas, as well as larger fragments.

Even after ejecting mini comets, the solid nucleus of comet Holmes survived and continued on its orbit, seemingly unperturbed.

Holmes takes about 6 years to circle the sun, and travels between the inner edge of the asteroid belt to beyond Jupiter. The comet is now moving away from the sun but will return to its closest approach in 2014, when astronomers will examine it for signs of further outbursts.

Stevenson will present the findings at the European Planetary Science Congress in Potsdam, Germany on Wednesday."<

posted in Astronomy - 1 reply

New Ganymede map - so don't get lost

idea1407 — Wed, 16 Sep 2009 17:29:30 GMT

http://www.space.com/scienceastronomy/090915-ganymede-map.html

>"New Map Reveals Geology of Jupiter's Moon Ganymede
By SPACE.com Staff

posted: 15 September 2009
08:43 pm ET

Jupiter's moon Ganymede, the largest moon in the solar system, now has a detailed global map that will help scientists better understand the large, icy satellite.

The map is the product of a seven-year effort and is only the third global geological map ever compiled for a moon in the solar system, after Earth's moon and Jupiter's cratered satellite Callisto.

"The map really gives us a more complete understanding of the geological processes that have shaped the moon we see today," said Wes Patterson, a planetary scientist at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., who led the map effort.

Patterson's team will present the map, created with data images from NASA's historic Voyager and Galileo missions, on Wednesday at the 2009 European Planetary Science Congress in Potsdam, Germany.

With a diameter of 3,280 miles (5,262 km), Ganymede is the largest moon in the solar system. Larger than both planet Mercury and dwarf planet Pluto, it's also the only satellite in the solar system known to have its own magnetosphere.

While scientists have crafted several regional geological maps of Ganymede's surface using Voyager data, Patterson's team was the first to combine the low-resolution Voyager photos with high-resolution Galileo images to create a global and consistent view of the moon's geology.

The new map details geologic features that formed and evolved over much of our solar system's history. These features record evidence of the internal evolution of this large icy satellite, of its dynamical interactions with the other Galilean satellites, and of the evolution of the population of small bodies impacting the surface of the satellite.

"By mapping the entirety of Ganymede's surface, we can more accurately address scientific questions regarding the formation and evolution of this truly unique moon," Patterson said. "Work done using the map by collaborator Geoff Collins at Wheaton College, for instance, has shown that vast swaths of grooved terrain covering the surface of the satellite formed in a specific sequence. The details of this sequence tell us something about the forces that must have been necessary to form those swaths."

Patterson says scientists can look at Ganymede's geological history as a "touchstone" for comparing and contrasting the characteristics and evolution of other large to mid-sized icy satellites. The map will also, he adds, be a reference for exploration of the Jovian system.

NASA and the European Space Agency are currently developing a future voyage: the Europa Jupiter System Mission would include orbiters of Ganymede as well as the icy satellite Europa.

"A primary goal of the next flagship mission to the Jupiter system will be to characterize, in detail, the geophysical, compositional, geological, and external processes that affect icy satellites," Patterson said. "This map will be an invaluable tool in determining how best to address those goals for Ganymede.""<

Map pic:
http://www.space.com/php/multimedia/imagedisplay/img_display.php?pic=090915-ganymede-map-02.jpg&cap=A+global+image+mosaic+of+Jupiter%27s+moon%2C+Ganymede+created+with+images+from+the+Voyager+and+Galileo+missions.+Credit%3A+Wes+Patterson

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NASA Creates Anti-Gravity Field, Makes Lab Rats Levitate

freetheweed — Thu, 10 Sep 2009 17:26:58 GMT

Not exactly astronomy but I'm sure we'll find applications for it in space soon enough

http://gizmodo.com/5356473/nasa-creates-anti%20gravity-field-makes-lab-rats-levitate

NASA scientists have created an anti-gravity field that works at room temperature, which is a big Where's My Back to the Future Skateboard breakthrough. The only problem is that it only works on mice. Mice high as kites, in fact.

Scientists at the Jet Propulsion Laboratory in Pasadena, California, have created a superconducting magnet that generates enough energy to lift small animals off the floor. The magnet pushes the water inside the animals up, making them fly. The amazing fact is that it works at room temperature—not the ultra-cooled down environments typical of these magnets—and it's large enough to make rodents to levitate.

The mice were high in more than one way, though. According to researcher Yuanming Liu, the "first mouse actually kicked around and started to spin, and without friction, it could spin faster and faster, and we think that made it even more disoriented." So they gave a mild sedative to the next mouse, who was happy to float.

posted in Astronomy - 11 replies

Kepler could find moons?

idea1407 — Thu, 03 Sep 2009 18:28:59 GMT

Space.com article:
http://www.space.com/scienceastronomy/090903-kepler-moons.html

>"Kepler Telescope Could Find Habitable Moons
By SPACE.com Staff

posted: 03 September 2009
11:21 am ET

NASA's planet-hunting Kepler telescope, which astronomers hope will find Earth-like planets orbiting other stars, might also find habitable moons in other solar systems, new research suggests.

Kepler's primary mission is to monitor thousands of stars looking for characteristic dips in their brightness as orbiting planets pass in front of them in so-called "transit" events.

The orbiting observatory, launched in March, already detected the giant extrasolar planet HAT-P-7b within its first 10 days of taking data. The planet had previously been discovered by ground-based telescopes, but the observations showed Kepler works as expected.

While ground-based observatories, and even some space telescopes, such as Spitzer and Hubble, can find Jupiter-sized extrasolar planets, Kepler is the first telescope aimed at detecting alien worlds closer to the size of our own home planet.

One astronomer suggests that Kepler's capabilities may even be able to detect so-called "exo-moons."

Modeling moons

David Kipping of University College London has already devised a method for detecting exomoons but no-one was sure whether it could really be used with current technology. He and his team have now modeled the properties of the instruments on Kepler, simulating the expected signal strength that a habitable moon would generate.

An exomoon's gravity tugs on the planet it orbits, making the planet wobble during its orbit around its host star. The resulting changes in the position and velocity of the planet should be detectable by Kepler through accurate timing of the transits.

The scientists considered a wide range of possible planetary systems and found that a fluffy Saturn-like planet, which would be low in mass for its size, gives the best possible chance for detecting a moon, rather than a denser Jupiter-like world. This is because planets like Saturn are large – blocking out a lot of light as they pass in front of their star – but very light, meaning they will wobble much more than a heavy planet.

If the Saturn-like planet is at the right distance from its star, then the temperature will allow liquid water to be stable on any sufficiently large moons in orbit around it. Such water-bearing moons might be habitable for life.

"For the first time, we have demonstrated that potentially habitable moons up to hundreds of light years away may be detected with current instrumentation," Kipping said.

Millions of moons possible

The team found that habitable exomoons down to 0.2 times the mass of the Earth are readily detectable with Kepler.

"As we ran the simulations, even we were surprised that moons as small as one-fifth of the Earth's mass could be spotted," Kipping said.

While it is not known if habitable exomoons are common in the galaxy, the observatory could potentially look for Earth-mass habitable moons around 25,000 stars up to 500 light-years away from the sun. In the whole sky, there should be millions of stars which could be surveyed for habitable exomoons with present technology.

"It seems probable that many thousands, possibly millions, of habitable exomoons exist in the Galaxy and now we can start to look for them," Kipping said.

The team's findings will be detailed later this month in the journal Monthly Notices of the Royal Astronomical Society."<

posted in Astronomy - 1 reply

New Space Tribe

idea1407 — Sat, 12 Sep 2009 19:05:17 GMT

Commercial Space is changing with the New Space companies like Virgin Galactic and SpaceX. So I am putting out an open invitation to all who is interested in the subject.

Recently Posts:

Re: SpaceX - $50M for Commerical Space crewed services:
http://tribes.tribe.net/newspace/thread/b8e298ac-a44e-4912-a6cc-3135e3119de6#387d0fdb-afbb-484e-9ddb-2c9923411a90

Commercial Crew Development
http://tribes.tribe.net/newspace/thread/87467f7c-a765-47f2-8597-8c782f89d66c#fa333654-4879-402f-95a9-62c1b81d45a3

posted in Astronomy - 0 replies

Galaxies Demand a Stellar Recount

Serge — Thu, 10 Sep 2009 20:04:52 GMT

Feature, August 19, 2009

For decades, astronomers have gone about their business of studying the cosmos with the assumption that stars of certain sizes form in certain quantities. Like grocery stores selling melons alone, and blueberries in bags of dozens or more, the universe was thought to create stars in specific bundles. In other words, the proportion of small to big stars was thought to be fixed. For every star 20 or more times as massive as the sun, for example, there should be 500 stars with the sun's mass or less.

This belief, based on years of research, has been tipped on its side with new data from NASA's Galaxy Evolution Explorer. The ultraviolet telescope has found proof that small stars come in even bigger bundles than previously believed; for example, in some places in the cosmos, about 2,000 low-mass stars may form for each massive star. The little stars were there all along but masked by massive, brighter stars.

"What this paper is showing is that some of the standard assumptions that we've had – that the brightest stars tell you about the whole population of stars – this doesn't seem to work, at least not in a constant way," said Gerhardt R. Meurer, principal investigator on the study and a research scientist at Johns Hopkins University, Baltimore, Md.

Astronomers have long known that many stars are too dim to be seen in the glare of their brighter, more massive counterparts. Though the smaller, lighter stars outnumber the big ones, they are harder to see. Going back to a grocery story analogy, the melons grab your eyes, even though the total weight of the blueberries may be more.

Beginning in the 1950s, astronomers came up with a method for counting all the stars in a region, even the ones they couldn't detect. They devised a sort of stellar budget, an equation called the "stellar initial mass function," to estimate the total number of stars in an area of the sky based on the light from only the brightest and most massive. For every large star formed, a set number of smaller ones were thought to have been created regardless of where the stars sat in the universe.

"We tried to understand properties of galaxies and their mass by looking at the light we can see," Meurer said.

But this common assumption has been leading astronomers astray, said Meurer, especially in galaxies that are intrinsically small and faint.

To understand the problem, imagine trying to estimate the population on Earth by observing light emitted at night. Looking from above toward North America or Europe, the regions where more people live light up like signposts. Los Angeles, for example, is easily visible to a scientist working on the International Space Station. However, if this method were applied to regions where people have limited electricity, populations would be starkly underestimated, for example in some sections of Africa.

The same can be said of galaxies, whose speckles of light in the dark of space can be misleading. Meurer and his team used ultraviolet images from the Galaxy Evolution Explorer and carefully filtered red-light images from telescopes at the Cerro Tololo International Observatory in Chile to show that many galaxies do not form a lot of massive stars, yet still have plenty of lower-mass counterparts. The ultraviolet images are sensitive to somewhat small stars three times or more massive than the sun, while the filtered optical images are only sensitive to the largest stars with 20 or more times the mass of the sun.

The effects are particularly important in parts of the universe where stars are spread out over a larger volume -- the rural Africa of the cosmos. There could be about four times as many stars in these regions than previously estimated.

"Especially in these galaxies that seem small and piddling, there can be a lot more mass in lower mass stars than we had previously expected from what we could see from the brightest, youngest stars," Meurer said. "But we can now reduce these errors using satellites like the Galaxy Evolution Explorer."

This research was published in the April 10, 2009, issue of Astrophysical Journal.

-end-

From: subscription email

posted in Astronomy - 1 reply

Hubble back in the saddle!

idea1407 — Thu, 10 Sep 2009 18:50:02 GMT

http://www.space.com/scienceastronomy/090909-new-hubble-images.html

>"Hubble Telescope is Back: Fantastic New Images Released
By Andrea Thompson
Senior Writer
posted: 09 September 2009
11:22 am ET

NASA's Hubble Space Telescope is back in action after its most recent upgrade, with a spectacular array of new images showing off the telescope's new capabilities.

Among the first images – a closely guarded secret until today – is one of galaxy NGC 6217. The picture was taken with NASA's newly refurbished Advanced Camera for Surveys (ACS).

This is "the day many of us have all been waiting for to celebrate Hubble's new beginning," said Ed Weiler, associate administrator for NASA's Science Mission Directorate at NASA Headquarters in Washington, D.C.

Hubble also snapped pictures of a group of five galaxies, a densely packed star cluster, an eerie "pillar of creation," and a "butterfly" nebula.

Scientists also released spectroscopic observations that slice across billions of light-years to probe the cosmic-web structure of the universe and map the distribution of elements that are fundamental to life as we know it.

Sen. Barbara A. Mikulski, D-Md., who has provided key support for Hubble and NASA in Congress, unveiled the images at NASA Headquarters. She was given the honorary title "Godmother of Hubble." Mikulski's district includes the Space Telescope Science Institute in Baltimore, where Hubble images are processed.

"I fought for the Hubble repair mission because Hubble is the people's telescope," said Mikulski, chairwoman of the Commerce, Justice and Science Appropriations Subcommittee that funds NASA.

Hubble's new instruments, including the Wide Field Camera 3, a new super-sensitive spectrograph, were installed on the 19-year-old telescope by shuttle astronauts during a 13-day service mission in May. The mission, which was initially cancelled in 2004 due to safety concerns after the 2003 Columbia shuttle disaster, also revived two instruments — Hubble's main ACS and a versatile imaging spectrograph — that were never designed to be fixed in space.

The new instruments are more sensitive to light and, therefore, will improve Hubble's observing efficiency significantly. It is able to complete observations in a fraction of the time that was needed with prior generations of Hubble instruments.

The WFC3 was actually used to take a picture of Jupiter's new black spot — thought to have been caused by a comet collision — back in July, but the camera wasn't yet fully calibrated then. WFC3 also took new images of the Omega Centauri star cluster in our galaxy, in which the contrast between hot and cool stars can vividly be seen, and the Butterfly Nebula, for which astronomers used the new filters on the camera to see the envelope of gas expanding away from this planetary nebula.

"We couldn't be happier about the way things have gone," Bob O'Connell, chair of the science oversight committee for the Wide Field Camera 3 at the University of Virginia. "We're fully confident the camera is working as it was intended to work."

Images taken with the new Cosmic Origins Spectrograph were taken in one-tenth of the time of Hubble's older spectrograph, which will allow scientists to view 10 times as many targets or look at targets one-tenth as bright, said James Green, the COS principal investigator at the University of Colorado. Scientists hope to build a catalogue of hundreds or thousands of targets and map the distribution of matter throughout the universe.

Hubble will also be able to continue observations of Eta Carinae, one of the most massive stars in the galaxy (and actually a pair of stars), that were suspended by instrument failure in 2004, said David Leckrone, senior project scientist for Hubble at NASA's Goddard Space Flight Center in Greenbelt, Md. Eta Carinae has erupted before and is expected to do so again.

Despite a few bumps in the three-month checkout, Hubble's systems and instruments are all up and running now.

NASA's new administrator Charlie Bolden was also on hand to congratulate the scientists and astronauts on Hubble's new lease on life. Bolden was one of the astronauts on the shuttle mission that deployed Hubble in 1990.

"Hubble has a special place in my heart," Bolden said. Through Hubble's past and future observations, "our view of the universe and our place within it will never be the same," he added."<

posted in Astronomy - 1 reply

NASA Researchers Make First Discovery of Life's Building Block in Comet

Serge — Thu, 10 Sep 2009 20:01:12 GMT

DC Agle 818-393-9011
Jet Propulsion Laboratory, Pasadena, Calif.
agle@jpl.nasa.gov

Dwayne Brown 202-358-1726
NASA Headquarters, Washington
dwayne.c.brown@nasa.gov

Nancy Neal Jones
Goddard Space Flight Center, Md.
301-286-0039/5017
nancy.n.jones@nasa.gov

News release: 2009-126, August 17, 2009

PASADENA, Calif. -- NASA scientists have discovered glycine, a fundamental building block of life, in samples of comet Wild 2 returned by NASA's Stardust spacecraft.

"Glycine is an amino acid used by living organisms to make proteins, and this is the first time an amino acid has been found in a comet," said Jamie Elsila of NASA's Goddard Space Flight Center in Greenbelt, Md. "Our discovery supports the theory that some of life's ingredients formed in space and were delivered to Earth long ago by meteorite and comet impacts."

Elsila is the lead author of a paper on this research accepted for publication in the journal Meteoritics and Planetary Science. The research was presented during the meeting of the American Chemical Society at the Marriott Metro Center in Washington, D.C., August 16.

"The discovery of glycine in a comet supports the idea that the fundamental building blocks of life are prevalent in space, and strengthens the argument that life in the universe may be common rather than rare," said Carl Pilcher, director of the NASA Astrobiology Institute, which co-funded the research.

Proteins are the workhorse molecules of life, used in everything from structures like hair to enzymes, the catalysts that speed up or regulate chemical reactions. Just as the 26 letters of the alphabet are arranged in limitless combinations to make words, life uses 20 different amino acids in a huge variety of arrangements to build millions of different proteins.

Stardust passed through dense gas and dust surrounding the icy nucleus of Wild 2 (pronounced "Vilt-2") on Jan. 2, 2004. As the spacecraft flew through this material, a special collection grid filled with aerogel – a novel sponge-like material that's more than 99 percent empty space – gently captured samples of the comet's gas and dust. The grid was stowed in a capsule that detached from the spacecraft and parachuted to Earth on Jan. 15, 2006. Since then, scientists around the world have been busy analyzing the samples to learn the secrets of comet formation and our solar system's history.

"We actually analyzed aluminum foil from the sides of tiny chambers that hold the aerogel in the collection grid," said Elsila. "As gas molecules passed through the aerogel, some stuck to the foil. We spent two years testing and developing our equipment to make it accurate and sensitive enough to analyze such incredibly tiny samples."

Earlier, preliminary analysis in the Goddard labs detected glycine in both the foil and a sample of the aerogel. However, since glycine is used by terrestrial life, at first the team was unable to rule out contamination from sources on Earth. "It was possible that the glycine we found originated from handling or manufacture of the Stardust spacecraft itself," said Elsila. The new research used isotopic analysis of the foil to rule out that possibility.

Isotopes are versions of an element with different weights or masses; for example, the most common carbon atom, Carbon 12, has six protons and six neutrons in its center (nucleus). However, the Carbon 13 isotope is heavier because it has an extra neutron in its nucleus. A glycine molecule from space will tend to have more of the heavier Carbon 13 atoms in it than glycine that's from Earth. That is what the team found. "We discovered that the Stardust-returned glycine has an extraterrestrial carbon isotope signature, indicating that it originated on the comet," said Elsila.

The team includes Daniel Glavin and Jason Dworkin of NASA Goddard. "Based on the foil and aerogel results it is highly probable that the entire comet-exposed side of the Stardust sample collection grid is coated with glycine that formed in space," adds Glavin.

"The discovery of amino acids in the returned comet sample is very exciting and profound," said Stardust Principal Investigator Donald E. Brownlee, a professor at the University of Washington, Seattle. "It is also a remarkable triumph that highlights the advancing capabilities of laboratory studies of primitive extraterrestrial materials."

The research was funded by the NASA Stardust Sample Analysis program and the NASA Astrobiology Institute. NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Stardust mission for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, developed and operated the spacecraft.

For images, visit: http://www.nasa.gov/mission_pages/stardust/news/stardust_amino_acid.html

-end-

From: subscription email

posted in Astronomy - 0 replies

HTV flight

idea1407 — Mon, 07 Sep 2009 21:14:50 GMT

http://www.space.com/missionlaunches/090904-japan-htv-ready.html

>"Japan's First Space Cargo Ship Ready to Fly
By Tariq Malik
Managing Editor
posted: 05 September 2009
01:29 pm ET

Japan's first unmanned spacecraft to haul cargo to the International Space Station (ISS) is nearly ready for its maiden launch next week.

The new cargo ship is poised to launch toward the station on Sept. 10 at 1:01 p.m. EDT (1701 GMT) from the Tanegashima Space Center in southern Japan on a shakedown cruise. If all goes well, the inaugural spacecraft, called the H-2 Transfer Vehicle 1 (HTV-1), should arrive at the station on Sept. 17.

The spacecraft was built by JAXA, Japan's space agency, and will launch atop the country's brand new H-2B rocket. It will be early Sept. 11 Local Time at the Japanese launch site at the time of liftoff.

"JAXA is ready to carry out the important HTV-1 mission as a new contribution to the ISS program," said Masazumi Miyake, director of the JAXA office at NASA's Johnson Space Center in Houston, in a Wednesday briefing.

JAXA mission managers are expected to hold a series of final readiness reviews for HTV-1 and its rocket booster to make sure it's ready for launch day. "<

posted in Astronomy - 2 replies

Pics of Triton

idea1407 — Wed, 09 Sep 2009 14:08:26 GMT

http://www.space.com/scienceastronomy/090908-st-neptune-pictures.html

>"New Pictures of Neptune's Moon Triton

By Clara Moskowitz
Staff Writer
posted: 08 September 2009
08:50 am ET

NASA released new pictures of Neptune's freezing moon Triton, made from data taken by the Voyager 2 spacecraft on its way out of the solar system in 1989.

The close-up shots reveal Triton's pockmarked surface, covered with crater scars from years of space rock impacts, as well as smooth volcanic plains, mounds and round pits formed by icy lava flows.

The photographs were released to commemorate the 20-year anniversary of the Voyager flyby of the moon, the last solid object visited by the spacecraft. The images were made using topographic maps derived from Voyager 2 photographs.

Among its discoveries at the moon, Voyager 2 revealed that Triton has active geysers. And with surface temperatures at minus 391 degrees Fahrenheit (minus 235 degrees Celsius), Neptune's largest moon is one of the coolest objects in the solar system.

The unmanned Voyager 2 probe launched in 1977 on a grand tour of the solar system, visiting Jupiter, Saturn, Uranus, and Neptune, as well as many of their moons, before moving on to interstellar space.

The probe is currently about 8.4 billion miles (13.5 billion km) from the sun, or almost 90 times the distance between the sun and Earth.

Voyager 2 and its sister, Voyager 1 (also launched in 1977, and currently the farthest away man-made object, at about 10 billion miles, or 16 billion km from the sun) are still operational and still transmitting data.

Both probes carry with them golden phonograph records with sounds chosen to communicate a sampling of humanity to any extraterrestrial life they may encounter. The contents, which include greetings in 55 languages, as well as music such as Bach's Brandenburg Concerto, gamelan music from Indonesia, Louis Armstrong's "Melancholy Blues," and many others, were chosen by a NASA committee headed by Carl Sagan."<

posted in Astronomy - 1 reply

Saturn Moon Could Power 150 Billion Labor Day Barbecues

Serge — Mon, 07 Sep 2009 01:09:49 GMT

Feature,
September 04, 2009

Since its discovery by Dutch astronomer Christiaan Huygens in 1655, Saturn's most massive moon, Titan, has been known as a place of mystery and intrigue. The large, cloud-enshrouded moon is such a scientific enigma that for the past five years, it has been targeted by NASAs Cassini spacecraft with more than 60 probing flybys. One of its latest findings could be a valuable asset to future generations of space explorers hunting for materials to whip up a Labor Day barbecue.

“Titan’s atmosphere is extremely rich in an assortment of hydrocarbon chemicals, including propane, which we use to fill our barbecue tanks,” said Cassini scientist Conor Nixon of the University of Maryland, College Park. "Titan’s atmospheric inventory would fuel about 150 billion barbecue cookouts, enough for several thousand years of Labor Days.”

For those who are burger, barbecue or Titan challenged, propane is a three-carbon alkane (a chemical compound consisting of carbon and hydrogen), that is non-toxic and heavier than air. With its low boiling point of minus 43.6 degrees Fahrenheit (minus 42 degrees Centigrade), propane vaporizes as soon as it is released from its pressurized container. Here on Earth, propane is commonly used as a fuel for forklifts, flamethrowers, residential central heating, portable stoves, hot air balloons, and – of course – barbecues. On other worlds propane is an untapped resource.

This gas of many terrestrial uses was first discovered in Titan's atmosphere back in 1980 when NASA's Voyager 1 spacecraft flew past the Saturnian system. Over the years, both ground and space-based instruments have added to the research, but accurately quantifying the amount of propane on Titan has proved elusive. Then, in 2004, the Cassini spacecraft entered orbit around Saturn.

Measuring the amount of propane on Titan is important to scientists because the gas is a very complex molecule, and its signature in the infrared spectrum is close to those of several molecules scientists are hoping to discover in Titan's atmosphere.

"It was not so much that measuring propane was our endgame, but it helps enormously in our hunt for other complex molecules," said Nixon. "These include pyrimidines that are potential building blocks for biological molecules, such as the nuceleobases of our DNA.” If we can detect them on Titan, that would be very significant."

Propane on Titan was measured using data from Cassini's Composite Infrared Spectrometer instrument. During multiple flybys of the moon between June 2004 and June 2008, the instrument measured infrared light from the edge of Titan's atmosphere. After a detailed analysis of the gas's characteristic ‘emission bands’ or signature, using computer predictions backed by the latest laboratory research into its infrared spectrum, the Composite Infrared Spectrometer team came up with an estimate of the amount of propane in Titan’s atmosphere So exactly how much propane does it take to fire 150 billion cookouts?

"We estimate there are nearly 700 million barrels of propane on Titan, said Nixon. "That is enough to fill six-billion 20-pound tanks of liquefied propane gas. It sounds like a huge amount, but that would satisfy total U.S. consumption of propane for only 18 months."

Which still leaves, with regards to Saturn's biggest moon, one Labor Day staple still to be determined. How many hamburgers could future generations of outer-planet explorers grill using Titan’s atmospheric propane?

"A dozen at a time, that’s two trillion hamburgers," said Cassini’s Nixon, "assuming you stop at medium-well."

Nixon is the lead author on a paper about propane on Titan to be published in an upcoming issue of Planetary and Space Science.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Cassini orbiter was designed, developed and assembled at JPL. JPL manages the mission for the Science Mission Directorate at NASA Headquarters in Washington. Cassini's Composite Infrared Spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md.

More information about the Cassini mission is available at http://www.nasa.gov/cassini or http://saturn.jpl.nasa.gov .

Doing the math: How do we get from “150 billion barbeque cookouts” to “two trillion” burgers?

You can fit 700 million barrels of propane into about six billion 20-pound tanks of liquefied propane gas (LPG). As most Labor Day cookouts will probably occur on this planet, we will use Earth as our barbecue laboratory. On Earth, a full tank of LPG burns for about nine hours – enough time to turn out 25 to 30 meals. That brings us to about 150 to 180 billion meals. If you average 12 medium-well patties per meal, then we’re talking about 2 trillion burgers. When it comes to figuring out how many hot dogs could be cooked, you’re on your own.

- end -

From: subscription email

posted in Astronomy - 3 replies

Milky Way Expected to Survive a Beating

Serge — Mon, 07 Sep 2009 17:59:02 GMT

By Clara Moskowitz
Staff Writer
posted: 07 September 2009
09:07 am ET

Though the Milky Way is taking a good beating from nearby mini-galaxies that sometimes slam into it, our galaxy is not likely to de destroyed by this process as some scientists had predicted, a new study finds.

Circling around the Milky Way, http://www.space.com/scienceastronomy/060227_mm_milky_way_tour.html , are between 20 and 25 known satellite dwarf galaxies, http://www.space.com/scienceastronomy/090804-st-dwarf-spheroidal-galaxies.html , which are smaller clumps of stars bound in orbit around the Milky Way by gravitational attraction.

Some pessimists predicted, http://www.space.com/scienceastronomy/astronomy/galaxy_collides_020507-1.html , the Milky Way was doomed to a grisly death by dismemberment if enough of these galaxies collide with it. In fact, scientists think many satellite galaxies have already rammed into the Milky Way, though so far it has endured.

A new computer simulation indicates that rather than tearing apart a galaxy, http://www.space.com/common/media/video/player.php?videoRef=070509Galaxy_collide , collisions with dwarf galaxies serve to puff up the host's pancake-shaped galactic disk. Indeed, evidence of this puffiness has been found in the form of rings and flares of stars around the edges of other galaxies' disks.

"Our simulations showed that the satellite galaxy impacts don't destroy spiral galaxies — they actually drive their evolution, by producing this flared shape and creating stellar rings — spectacular rings of stars that we've seen in many spiral galaxies in the universe," said study leader Stelios Kazantzidis, an astronomer at Ohio State University.

Though our galaxy may not be in danger from dwarf galaxies, astronomers do expect it to eventually collide with the nearest full-size galaxy, Andromeda. In a few billion years, the two spirals should smash into each other head on.

"The collision with Andromeda is a collision between two essentially equal-mass galaxies, whereas satellite bombardment involves encounters with much smaller systems compared to the Milky Way," Kazantzidis told SPACE.com.

Luckily, even that fender bender doesn't necessarily spell the end for the galaxies' inhabitants. Stars are generally spaced wide enough apart within the galaxies that after the merger, most individual stars should intermingle without actually crashing into each other.

In fact, the merging will likely set off a firestorm of new star formation, adding to the richness of the two melded galaxies.

The new simulation helps scientists understand how smaller collisions affect a galaxy's development.

"We can't know for sure what's going to happen to the Milky Way, but we can say that our findings apply to a broad class of galaxies similar to our own," Kazantzidis said.

The model is the most detailed to date of collisions between spiral galaxies and satellites. It revealed the kind of detailed features that should result from these impacts, which align well with observed characteristics of other galaxies seen in the universe.

"Every spiral galaxy has a complex formation and evolutionary history," Kazantzidis said. "We would hope to understand exactly how the Milky Way formed and how it will evolve...

The research is detailed in two papers published in the Astrophysical Journal in August 2009 and November 2008.

Original Story: http://www.space.com/scienceastronomy/090907-mm-milky-way-survive.html

posted in Astronomy - 1 reply

Free Public Lectures Will Preview Next Mars Landing

Serge — Wed, 19 Aug 2009 18:46:44 GMT

Guy Webster (818) 354-6278
Jet Propulsion Laboratory, Pasadena, Calif.
Guy.webster@jpl.nasa.gov

News release: 2009-128, August 18, 2009

PASADENA, Calif. -- Two free public programs in Pasadena this week will explain why previous methods of landing on Mars would not work for the next Mars rover and will describe how engineers developed a new sky-crane system for this mission, NASA's Mars Science Laboratory.

Tom Rivellini of NASA's Jet Propulsion Laboratory in Pasadena, will present illustrated talks about Mars landing methods on Thursday, Aug. 20, at JPL, with a live webcast, and on Friday, Aug. 21, at Pasadena City College. Both lectures will begin at 7 p.m. PDT.

Rivellini is one of JPL's principal mechanical engineers for spacecraft descent and landing systems.

In 2012, the Mars Science Laboratory mission's rover, Curiosity, will use a heat shield and parachute for initial phases of its descent through the Martian atmosphere. Then a rocket-powered descent stage will slow almost to a hover and unspool a tether, lowering the rover directly onto the surface.

Seating is first-come, first-served. The Thursday lecture will be in JPL's von Kármán Auditorium. JPL is at 4800 Oak Grove Dr., off the Oak Grove Drive exit of the 210 (Foothill) Freeway. The Friday lecture will be in Pasadena City College's Vosloh Forum, 1570 E. Colorado Blvd. For more information, call (818) 354-0112.

For information on how to view the live webcast on Thursday and to see an archived video later, visit http://www.jpl.nasa.gov/events/lectures.cfm?year=2009&month=8 . More information about the Mars Science Laboratory mission is at http://mars.jpl.nasa.gov/msl/ .

- end -

From: subscription email

posted in Astronomy - 4 replies

Lack of Gravity Waves

idea1407 — Tue, 01 Sep 2009 16:48:21 GMT

http://www.space.com/scienceastronomy/090819-gravitational-waves.html

>"Lack of Gravity Waves Puts Limits on Exotic Cosmology Theories
By Clara Moskowitz
Staff Writer
posted: 19 August 2009
02:36 pm ET

This time, scientists are excited to find nothing.

In results announced today, a huge physics experiment built to detect gravitational waves has yet to find any.

Rather than be disappointed by the null findings, physicists say the results were expected, and in fact help them narrow down possibilities for what the universe was like just after it was born.

The Laser Interferometer Gravitational-Wave Observatory Scientific Collaboration (LIGO) is a set of instruments in Louisiana and Washington built to search for evidence of gravitational waves, which are theoretical ripples in space-time thought to be caused by the acceleration of mass. No one has yet directly detected these waves, though they are predicted by Einstein's theory of General Relativity, and are widely thought to permeate our universe.

In theory, every time mass accelerates - even when you rise up out of your chair - the curvature of space-time changes, and ripples are produced. However, the gravitational waves produced by one person are so small as to be negligible. The waves produced by large masses, though, such as the collision of two black holes or a large supernova explosion, could be large enough to be detected."<

posted in Astronomy - 5 replies

Solar Systems Warped by Interstellar Wind

idea1407 — Tue, 01 Sep 2009 16:21:00 GMT

A Space.com article:

http://www.space.com/scienceastronomy/090901-st-warped-debris-disk.html

>"Solar Systems Warped by Interstellar Wind

By SPACE.com Staff

posted: 01 September 2009
10:56 am ET

Close encounters with interstellar gas could have given the dust-filled disks of solar systems — where planets are thought to form — the odd shapes that some of them have taken on, a new study suggests.

Stars across the galaxy have disks of dusty debris generated by the collisions of small comet- and asteroid-like bodies orbiting each star.

Astronomers have noticed that many of these debris disks are a bit wonky-looking, with lobes of dust sticking out in odd directions. One team noticed just such an oddly-shaped disk while using the Hubble Space Telescope to investigate the composition of the dust around the star HD 32297, which lies 340 light-years away from Earth in the constellation Orion.

John Debes of NASA's Goddard Space Flight Center in Greenbelt, Md., noticed that the interior portion of this star's dusty disk — a region comparable to the size of our own solar system — was warped in a way that was similar to other distant star systems.

Astronomers have previously attributed these warped shapes to the presence of undiscovered planets or past encounters with another star. But Debes and his colleagues used a model to show that the odd shapes aren't likely due to one of these exotic factors, but instead are likely caused by the interstellar environment that the star and its attendant disk are moving through.

"It's important to consider the ecology of these debris disks before running to such conclusions, and this model explains a lot of the weirdly shaped disks we see," Debes said."<

posted in Astronomy - 5 replies

ISRO loses radio contact with Chandrayaan-1

freetheweed — Sat, 29 Aug 2009 20:55:58 GMT

http://www.hindu.com/2009/08/30/stories/2009083053760100.htm

ISRO loses radio contact with Chandrayaan-1

T.S. Subramanian

India’s first moon mission cut short; a lot of data gained

CHENNAI: In a major blow to India’s maiden mission to the moon, the Indian Space Research Organisation (ISRO) abruptly lost contact with Chandrayaan-1 at 01.30 a.m. on Saturday. This means no command can be given to the spacecraft and no data, including images of the moon’s surface, are being received from it.

The Chandrayaan-1 mission has come to an end in ten months instead of its slated life of two years.

“We are not able to give commands to the spacecraft,” S. Satish, Director, Publications and Public Relations Department of ISRO, told The Hindu. “We are not able to establish communication with it, with the result that we do not know what is happening.”

The Indian Deep Space Network (IDSN) at Byalalu village, near Bangalore, received data from Chandrayaan-1 till an hour before radio contact was lost. The IDSN, with its huge antennae with diameters of 32 metres and 18 metres, is the hub of communications from the ground with the spacecraft. It is from Byalalu that commands were radioed to the spacecraft to perform various manoeuvres. Images from Chandrayaan-1 were also received here.

India’s first spacecraft to the moon was launched on October 22, 2008 from Sriharikota. An ISRO press release noted on Saturday that the spacecraft had completed 312 days in orbit, making more than 3,400 orbits around the moon. It provided a large amount of data from its sophisticated instruments such as the Terrain Mapping Camera, the Hyper-Spectral Imager, the Moon Mineralogy Mapper and so on. ISRO claimed that the mission had met most of its scientific objectives.

Chandrayaan-1 sent back more than 70,000 images of the lunar surface, which provided breathtaking views of lunar mountains and craters, especially craters in the permanently shadowed areas of the moon’s polar region. It also collected data on the chemical and mineral content of the moon’s soil.

But the troubles that have cut short the life of the moon mission began in November itself when the spacecraft’s power subsystems started failing one by one. In April, the mission went into a crisis, with the primary star-sensor and the backup star-sensor failing. But top ISRO officials appeared keen to play down the setbacks, with a May 20 press release making no mention of the failure of the star-sensors and the power units.

Asked what could have gone wrong with the spacecraft, Mr. Satish said: “Some electronic sub-system could have malfunctioned. We are looking at the telemetry data and trying to find out what is the problem. Using the telemetry data [received till contact with the spacecraft was lost], the health of the spacecraft is being analysed. It is expected to throw light on the problem noticed. ISRO’s stations are trying to revive the spacecraft.”

Asked whether Chadrayaan-1 was drifting away from its orbit, Mr. Satish said it was “definitely in orbit.” However, if the present situation continued, the orbit could be disrupted.

ISRO experts explained that all communication with Chandrayaan-1 and the receipt of data from it were handled through on-board electronic systems. “If radio contact with Chandrayaan is suddenly lost,” a top expert pointed out, “only electronic systems on the spacecraft could have failed. Otherwise, this could not have happened. From the symptoms, it looks as if the electronics failed.”

A Polar Satellite Launch Vehicle (PSLV) of ISRO put Chandrayaan-1 in its initial orbit. The spacecraft carried 11 instruments on board. One of them named the Moon Impact Probe (MIP) “impacted” on the lunar surface on November 14, 2008, signalling India’s success in reaching the moon.

posted in Astronomy - 10 replies

Space shuttle lifts off for ISS

freetheweed — Sun, 30 Aug 2009 10:29:18 GMT

http://news.bbc.co.uk/2/hi/science/nature/8228089.stm

Space shuttle lifts off for ISS

Space shuttle takes off at the third attempt

Nasa has launched the US shuttle Discovery for a mission to the International Space Station (ISS), with seven astronauts on board.

It lifted off from the Kennedy Space Center in Florida at 2359 EDT Friday (0359 GMT Saturday).

Two previous attempts to launch the orbiter had been postponed by a mix of bad weather and a technical glitch affecting its main propulsion system.

Discovery's mission will be the 30th flight dedicated to ISS maintenance.

Science equipment and a freezer to store research samples are among the items on board.

It also carries a new sleeping compartment, an air purification system and a treadmill to help maintain astronauts' health.

The shuttle entered orbit eight-and-a-half minutes after launch, and is due to arrive at the ISS on Sunday night.

Six sorties

Nasa plans an additional six sorties to the orbiting platform before retiring its re-useable spaceship fleet at the end of next year or early in 2011.

Managers had been discussing an early Friday flight but decided to give their engineers an extra 23 hours to study the hydrogen stop-drain fuel-valve problem that thwarted the second launch effort on Wednesday.

Engineers now believe the unexpected signals they were getting from the propulsion system while filling the orbiter's giant external tank on Tuesday were related to a errant sensor.

Heavy rain and lightning had intervened at the first launch attempt on Tuesday morning.

Discovery's 13-day mission is scheduled to include three spacewalks to replace exterior science experiments, prepare the platform for the arrival of a new module next year, and to install a new ammonia storage tank and return the used one.

Ammonia is used to move excess heat from inside the station to the radiators outside.

Discovery will also drop off US astronaut Nicole Stott for a three-month stay on the ISS, and pick up colleague Tim Kopra for the ride home. Kopra has been living on the platform for the past six weeks.

The mission is commanded by Rick Sturckow.

posted in Astronomy - 3 replies

Fog on Titan?

Hummingbird — Thu, 27 Aug 2009 20:37:39 GMT

http://www.mikebrownsplanets.com/2009/08/fog-titan-titan-fog-and-peer-review.html

"Titan has fog at the south pole! All of those bright sparkly reddish white patches are fog banks hanging out at the surface in Titan's late southern summer."

posted in Astronomy - 10 replies

Lost Moderator

Serge — Sat, 15 Aug 2009 06:55:47 GMT

Hello Everyone,
For a while by now, I have been trying to get in touch with Damian, this tribe's moderator, and it seems like he has abandoned it/us. His little red light is no longer on, (ever), and he does not reply to any PM's.
Therefore, due to the absence of ANY reasonable mean to get in touch with him, I am putting forward a request to elect a new moderator, and give my vote to Eric, ( http://people.tribe.net/idea1407 ). He has shown a keen interest in the topic here, as well as in his own, (related), tribe, while always being respectful of opinions of others, and ready to listen as well as actively participate in discussions.
...
Everyone is welcome to vote in this thread for a week, beginning now, 12:00 am, Saturday, August 14th.
The last vote will be counted in at 12:00 am, Saturday, August 21st, after which, I will contanct Tribe.net and inform them of the outcome of the elections.

Regards,
Serge

posted in Astronomy - 26 replies

Cosmic Rays

idea1407 — Thu, 27 Aug 2009 19:41:55 GMT

Space.com article:
http://www.space.com/scienceastronomy/090827-cosmic-rays.html

>"Death Rays From Space: How Bad Are They?
By Michael Schirber
Astrobiology Magazine
posted: 27 August 2009
11:53 am ET

Cosmic rays pour down on Earth like a constant rain. We don't much notice these high-energy particles, but they may have played a role in the evolution of life on our planet.

Some of the mass extinctions identified in the fossil record can be linked to an asteroid impact or increased volcanism, but many of the causes of those ancient die-offs are still open for debate.

"There may have been nearby astronomical goings-on that drastically increased the radiation on Earth," says Brian Fields from the University of Illinois.

A supernova going off 30 light-years away could cause such a jump in radiation on our planet that could directly, or indirectly, wipe out huge numbers of species. Currently researchers are looking for possible evidence for this sort of cosmic foul play.

"Just finding dead beasties is not proof of a nearby supernova," Fields says.

A hard rain is going to fall

Cosmic rays are mostly high-energy protons originating from supernova shock waves. We can't precisely trace where a cosmic ray came from because its trajectory is bent by magnetic fields. In fact, a typical cosmic ray will bounce inside the galaxy's magnetic field for millions of years before eventually colliding with something... like Earth.

"Every square centimeter on the top of the Earth's atmosphere is hit by several cosmic rays per second," Fields says. "This is forever going on."

None of these "primary" cosmic rays ever reach us on the ground. Instead, they collide with atoms in the upper atmosphere, creating a shower of lower energy "secondary" particles.

Secondary effects

At sea level, the majority of cosmic ray secondaries are highly penetrating muons. About 10,000 muons pass through our bodies every minute. Some of these muons will ionize molecules as they go through our flesh, occasionally leading to genetic mutations that may be harmful.

At present, the average human receives the equivalent of about 10 chest X-rays per year from cosmic rays. We shouldn't be alarmed by this, since it is just part of the natural background radiation under which humans and our ancestors have been exposed to for eons. Indeed, cosmic-ray-induced mutations may sometimes be beneficial.

"It is clear that in some way cosmic rays shaped evolution of organisms on Earth," says Franco Ferrari from the University of Szczecin in Poland.

In a recent issue of the journal Astrobiology, Ferrari and Ewa Szuszkiewicz from the same university reviewed what we know about cosmic rays, and they argue that the current biological relevance of these particles is not necessarily representative of the past.

"It is very likely that organisms of early Earth possessed DNA that was unstable and could easily mutate under external agents, more so, perhaps, than the DNA of present-day bacteria," the authors write.

Cosmic ray storm

Not only might biology have been more susceptible to mutation long ago, but the cosmic rays might have been more intense in the past, affecting both Earth's atmosphere and the life below.

One controversial theory suggests cosmic rays can increase cloud production. Cloudier skies bounce more sunlight off into space, cooling the planet and leading to widespread ecosystem changes. Another theory about increased cosmic radiation has nearly the opposite effect -- by stripping away our protective ozone layer, the Earth would have been blasted by more solar UV radiation. All that extra UV would have created hostile conditions for life.

Ozone depletion also could arise from a nearby gamma ray burst. However, the radiation flash would last only a second, and the ozone would recover after a few years. In contrast, cosmic rays from a nearby supernova would bombard Earth for at least 1,000 years, according to Fields.

"An organism might be able wait out a gamma ray burst, but cosmic rays are going to affect many generations," he says.

Near miss

One way to tell whether an extinction event was due to cosmic rays is to look for radioactive isotopes that would have formed in a nearby supernova and then were blown onto our planet by the associated blast wave.

In 1999, a group from the Technical University of Munich in Germany detected iron-60 in rock samples from the deep ocean. This extremely rare iron isotope is forged in the fires of supernovae. It is also radioactively unstable, with a half-life of 1.5 million years, so it must have come from a fairly recent supernova.

From the iron-60's location and concentration, the German group later calculated that the putative supernova went off 2.8 million years ago at a distance of about 100 light years away. Fields believes this was probably too far away to have caused an extinction-level event.

"I'd call it a near miss," he says.

The cosmic rays from this supernova may have had an effect on the climate, but to cause serious biological damage, a supernova would need to explode within about 30 light years of Earth.

Cosmic ray roulette

Although 30 light-years is small on a galactic scale, Fields thinks it likely that Earth has been caught in a supernova "kill radius" as many as a dozen times over our 4.5-billion-year history.

However, a nearby supernova is not the only way to increase the cosmic ray intensity. As our Sun orbits around the galactic center, it regularly passes through one of the galaxy's spiral arms where the cosmic ray radiation is higher than average, says Ferrari. Some researchers speculate that each passage through a spiral arm spawns an Ice Age on Earth through cosmic-ray-induced cloud formation.

In a similar vein, Melott and his colleagues found a possible link between the bobbing of our Sun up and down in the galactic plane and a 63-million-year cycle in fossil biodiversity. The hypothesis is that our solar system is exposed to more cosmic rays every time the solar system peaks out of one side of the galaxy.

However, Melott now thinks this bobbing may only play a small part, seeing as recent evidence points to a correlation between continental uplift and the observed biodiversity cycle.

More work is definitely needed to tie cosmic rays to extinction events. Melott says that the search continues for other radioactive isotope evidence of nearby supernovae, and his group is developing simulations of cosmic ray bombardment to see if there might be any recognizable pattern to the biological destruction.

"No one has calculated the full effects on the ground," he says."<

posted in Astronomy - 0 replies

Suicidal planet seems on death spiral into star

Serge — Wed, 26 Aug 2009 21:56:00 GMT

Science Writer Seth Borenstein,
Ap Science Writer – Wed Aug 26, 1:00 pm ET

WASHINGTON – Astronomers have found what appears to be a gigantic suicidal planet.

The odd, fiery planet is so close to its star and so large that it is triggering tremendous plasma tides on the star. Those powerful tides are in turn warping the planet's zippy less-than-a-day orbit around its star.

The result: an ever-closer tango of death, with the planet eventually spiraling into the star.

It's a slow death. The planet WASP-18b has maybe a million years to live, said planet discoverer Coel Hellier, a professor of astrophysics at the Keele University in England. Hellier's report on the suicidal planet is in Thursday's issue of the journal Nature.

"It's causing its own destruction by creating these tides," Hellier said.

The star is called WASP-18 and the planet is WASP-18b because of the Wide Angle Search for Planets team that found them.

The planet circles a star that is in the constellation Phoenix and is about 325 light-years away from Earth, which means it is in our galactic neighborhood. A light-year is about 5.8 trillion miles.

The planet is 1.9 million miles from its star, 1/50th of the distance between Earth and the sun, our star. And because of that the temperature is about 3,800 degrees.

Its size — 10 times bigger than Jupiter — and its proximity to its star make it likely to die, Hellier said.

Think of how the distant moon pulls Earth's oceans to form twice-daily tides. The effect the odd planet has on its star is thousands of times stronger, Hellier said. The star's tidal bulge of plasma may extend hundreds of miles, he said.

Like most planets outside our solar system, this planet was not seen directly by a telescope. Astronomers found it by seeing dips in light from the star every time the planet came between the star and Earth.

So far astronomers have found more than 370 planets outside the solar system. This one is "yet another weird one in the exoplanet menagerie," said planet specialist Alan Boss of the Carnegie Institution of Washington.

It's so unusual to find a suicidal planet that University of Maryland astronomer Douglas Hamilton questioned whether there was another explanation. While it is likely that this is a suicidal planet, Hamilton said it is also possible that some basic physics calculations that all astronomers rely on could be dead wrong.

The answer will become apparent in less than a decade if the planet seems to be further in a death spiral, he said.

___

On the Net

Nature: http://www.nature.com/nature
WASP group: http://www.superwasp.org/

From: Yahoo! News

posted in Astronomy - 5 replies

Tribe Preamble

idea1407 — Tue, 25 Aug 2009 02:59:52 GMT

The tribe preamble reads:
"Stargazing and planetwatching. Armchair cosmologists welcome. "

Should this be modified?

posted in Astronomy - 10 replies

South Korea launches its first rocket into space - 25 Aug 09

freetheweed — Tue, 25 Aug 2009 13:48:20 GMT

http://www.youtube.com/watch?v=Y49qg-033QU&feature=sub

South Korea has launched its first rocket into space just a week after the Naro Space Centre abandoned a first attempt because of a software glitch.

Seoul says the launch is meant to get the country into the satellite market, but North Korea remains skeptical.

Al Jazeera's Tony Birtley reports from Seoul, the South Korean capital.

http://news.bbc.co.uk/2/hi/asia-pacific/8219669.stm

S Korean launch 'partial success'

South Korea has launched its first space rocket, though a scientific satellite it was carrying failed to enter into its proper orbit.

South Korean officials described the launch as a "partial success".

Millions of South Koreans watched the launch, but it is being viewed with suspicion by North Korea.

The North was recently subjected to UN sanctions for its own rocket launch, which was widely regarded as a cover for a long-range missile test.

There was no immediate reaction from North Korea to Tuesday's launch.

Overshot orbit

South Korea's two-stage Naro rocket lifted off on Tuesday from an island off the south coast.

The satellite was placed into orbit but was not following its intended course, according to Science and Education Minster Ahn Byong-man.

"All aspects of the launch were normal, but the satellite exceeded its planned orbit," he was quoted as saying.

The satellite had reached an altitude of 360km (225 miles), rather than separating at the intended 302km, he said.

South Korean and Russian scientists were investigating the problem, he added.

Experts at the Korea Aerospace Research Institute were cited by local media as saying they were trying to track the satellite.

A statement from the science ministry called the launch a "partial success", while South Korean President Lee Myung-bak called it a "half-success".

'Potential military uses'

The rocket - 33m (108 ft) long and weighing some 140 tonnes - was the country's half-a-billion dollar bid to join the exclusive club of spacefaring nations.

Its Russian liquid-fuelled first-stage was said to have 1,700 kilonewtons of thrust at launch.

The second stage, burning a solid fuel, was produced by South Korean engineers.

Generating 80kN of thrust, it was intended to carry the Earth observation satellite into its final orbit.

South Korea initially planned to launch the rocket in late July, but delayed it several times due to technical problems.

South Korea has previously sent satellites into space using launch vehicles and rockets from other countries.

Seoul has rejected any comparison with Pyongyang's rocket launch and says its rocket is part of a peaceful civilian space programme.

But some security analysts have suggested a commercial space programme could still alter the long-term strategic balance in the region, as all rocket technology has potential military uses.

No North Korean satellite has been detected in space, although Pyongyang insists its rocket launch worked and the device is now orbiting the earth transmitting revolutionary melodies.

posted in Astronomy - 1 reply

Pluto...Superstar?

idea1407 — Mon, 24 Aug 2009 20:13:22 GMT

CNN article

http://www.cnn.com/2009/TECH/space/08/24/pluto.dwarf.planet/index.html

>"By A. Pawlowski
CNN
Decrease font Decrease font
Enlarge font Enlarge font

(CNN) -- For one of the farthest, coldest places in the solar system, Pluto sure stirs a lot of hot emotions right here on Earth.
This montage of images taken by Voyager shows, from left to right, Neptune, Uranus, Saturn and Jupiter.

This montage of images taken by Voyager shows, from left to right, Neptune, Uranus, Saturn and Jupiter.

It was three years ago Monday that the International Astronomical Union demoted Pluto from a planet to a dwarf planet, a decision that made jaws drop around the world.

An outcry followed, textbooks had to be rewritten, long-held beliefs were shattered, and many people felt our cosmic neighborhood just didn't seem the same with eight -- instead of nine --planets in the solar system.

Today, debate still rages over how to classify the little celestial body, along with others orbiting the sun, but the IAU stands by its definition.

"I think that most of the astronomical community has come to terms with the fact that we now know that the solar system has a continuous distribution of objects from very large down to very small," said Lars Lindberg Christensen, a spokesman for the IAU.

"We now know that what we call the different objects has to necessarily change with time."

Don't tell that to Plutophiles still seething about the decision. Some are even taking action.

Earlier this year, the Illinois Senate adopted a resolution declaring that Pluto was "unfairly downgraded" and restoring "full planetary status" to the celestial body as it "passes overhead through Illinois' night skies."

It also designated March 13, 2009, as "Pluto Day" in honor of the date that its discovery was announced in 1930. (In case you are wondering why the state is so passionate about Pluto: Clyde Tombaugh, who discovered the planet-now-dwarf-planet, was born in Illinois.)

Meanwhile, New Mexico's House of Representatives proclaimed February 18, 2009, as "Pluto is a Planet in New Mexico Day" and praised Tombaugh, who worked in the state for decades and died there in 1997.

Passionate about Pluto

Don't live in those states and want to make your voice heard? You can order "Plutophile" bumper stickers to proclaim your firm support for Pluto, print out a Pluto Fan Club card -- which allows you to declare, "In my heart, Pluto will always be a planet" -- or sign an online petition.
What's Pluto like?
• Pluto's average distance from the sun is about 3.6 billion miles

• The temperature on Pluto may be about -375 °F

• Pluto is mostly brown

• It takes Pluto 248 Earth years to travel once around the sun

• Pluto cannot be seen without a telescope

• Pluto's diameter is about 1,400 miles, smaller than Earth's moon

Source: World Book at NASA

Christensen said 90 percent of the critical e-mails and letters the IAU received after its decision in 2006 came from North America.

Astrophysicist Neil deGrasse Tyson, director of New York City's Hayden Planetarium and author of "The Pluto Files," believes there are two reasons why Americans are so engaged in the issue.

"Disney's dog Pluto was sketched the same year the cosmic object was discovered. And Pluto was discovered by an American. So here you have a recipe for Americans falling in love with a planet that really is just a tiny ice ball," Tyson told Time magazine.

Still, astronomers are divided about the best way to classify Pluto. See photos of other planets and find out what makes them stand out »

At the heart of the matter lies the question: What makes a planet in the solar system?

According to the IAU's definition, it must orbit the sun, it must be big enough for gravity to crush it into a nearly round shape, and it must clear the neighborhood around its orbit. In other words, it must be dominant enough to clear away objects in its orbital space, according to NASA.

This last point is what proved to be Pluto's demise as a planet: There are other competing objects in its orbit.

Crowded solar system?

Some scientists say that part of the definition doesn't make sense.

"It's kind of like, I'm going to tell you what your car is on the basis of how the traffic around you is behaving," said Mark Sykes, director of the Planetary Science Institute.

The more logical way to classify planets is the geophysical definition, which simply states that planets are round objects that orbit the sun, Sykes argues. The objects must still be big enough so that gravity crushes them into a ball.
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* Telescopes to show universe soon after Big Bang

"The problem with the geophysical definition is we might have a couple of dozen planets in the solar system as more are discovered in the distant reaches," Sykes said.

He believes the International Astronomical Union's definition won't stick around after NASA spacecraft reach Pluto and Ceres, a Texas-size asteroid in an orbit between Mars and Jupiter that is now also classified as a dwarf planet.

"I think [the IAU's definition] is going to collapse by 2015 when the Dawn mission gets to Ceres and the New Horizons mission gets to Pluto because we're not going to see irregular-shaped, impact crater-filled, boring surfaces. We're going to see dynamic worlds," Sykes said.

The IAU's decision also came under fire because only 4 percent of its scientists participated in the vote that reclassified Pluto. But Christensen said the IAU was following its statutes and bylaws and has passed other resolutions in a similar way.

The subject of Pluto didn't come up at the IAU's general assembly earlier this month in Rio de Janeiro, Brazil, Christensen added.
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Sykes countered that astronomers wanted to discuss the issue, just as they have at other recent major meetings, but the IAU didn't allow there to be any sessions on planet classification.

"I think the IAU did a terrible disservice to science, because it gives the public the impression that science is done by votes," Sykes said. "And that's not the way science is done at all." "<

posted in Astronomy - 0 replies

LCROSS peeks at the Earth and moon

idea1407 — Mon, 24 Aug 2009 20:06:10 GMT

http://www.nasa.gov/mission_pages/LCROSS/multimedia/EarthLookcont.html

>"More Images from the LCROSS Earth/Moon Look Calibration on Aug. 17, 2009"<

posted in Astronomy - 0 replies

Black Holes: The Other Side of Infinity

freetheweed — Sun, 23 Aug 2009 09:31:46 GMT

http://www.hulu.com/watch/14906/black-holes-the-other-side-of-infinity

Black Holes: The Other Side of Infinity

There are places where gravity is so powerful nothing can escape, where time and space literally crash into the abyss. Can you feel the pull? Narrated by Liam Neeson. 23 minutes

posted in Astronomy - 1 reply

Big Wave

idea1407 — Mon, 24 Aug 2009 19:37:52 GMT

http://www.space.com/scienceastronomy/090817-dark-energy-alternative.html
>"'Big Wave' Theory Offers Alternative to Dark Energy
By Clara Moskowitz
Staff Writer
posted: 17 August 2009
05:56 pm ET

This story was updated at 2:40 p.m. on Aug. 18.

Mathematicians have proposed an alternative explanation for the accelerating expansion of the universe that does not rely on the mystifying idea of dark energy.

According to the new proposition, the universe is not accelerating, as observations suggest. Instead, an expanding wave flowing through space-time has caused distant galaxies to appear to be accelerating away from us. This big wave, initiated after the Big Bang that is thought to have sparked the universe, could explain why objects today appear to be farther away from us than they should be according to the Standard Model of cosmology.

"We're saying that maybe the resulting expanding wave is actually causing the anomalous acceleration," said Blake Temple of the University of California, Davis. "We're saying that dark energy may not really be the correct explanation."

The researchers derived a set of equations describing expanding waves that fit Einstein's theory of general relativity, and which could also account for the apparent acceleration. Temple outlines the new idea with Joel Smoller of the University of Michigan in the Aug. 17 issue of the journal Proceedings of the National Academy of Sciences.

While more research will be needed to see if the idea holds up, "the research could change the way astronomers view the composition of our universe," according to a summary from the journal.

To convince other cosmologists, the new model will have to pass muster with further inquiry.

"There are many observational tests of the standard cosmological model that the proposed model must pass, aside from the late phase of accelerated expansion," said Avi Loeb, director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics. "These include big bang nucleosynthesis, the quantitative details of the microwave background anisotropies, the Lyman-alpha forest, and galaxy surveys. The authors do not discuss how their model compares to these tests, and whether the number of free parameters they require in order to fit these observational constraints is smaller than in the standard model. Until they do so, it is not clear why this alternative model should be regarded as advantageous."

Johns Hopkins University astrophysicist Mario Livio agreed that to be seriously considered, the model must be able to predict properties of the universe that astronomers can measure.

He said the real test "is in whether they are able to reproduce all the observed cosmological parameters (as determined, e.g. by a combination of the Hubble Constant and the parameters determined by the CMB observations). To only produce an apparent acceleration is in itself interesting, but not particularly meaningful."

Inconvenient truths

Dark energy is itself a hasty fix to an inconvenient truth discovered by astronomers in the late 1990s: that the universe is expanding, and the rate of this expansion seems to be constantly picking up speed.

To explain this startling finding, cosmologists invoked dark energy, a hypothetical form of energy that is pulling the universe apart in all directions (note that dark energy is wholly separate from the equally mysterious concept of dark matter - a hypothetical form of matter that populates the universe, interacting gravitationally with normal matter, but which cannot be seen with light). In this interpretation, the whole universe is blowing up like a balloon, and from any given point within it, all distant objects appear to be speeding away from you.

But not everyone is happy with the dark energy explanation.

"It just seems like an unnatural correction to the equations - it's like a fudge factor," Temple told SPACE.com. "The equations don't make quite as much physical sense when you put it in. You just put it in to fit the data."

Temple and Smoller think the idea of an expanding wave makes more sense.

"At this stage we think this a very plausible theory," Temple said. "We're saying there isn't any acceleration. The galaxies are displaced from where they're supposed to be because we're in the aftermath of a wave that put those galaxies in a slightly different position."

Ripples in a pond

Temple compared the wave to what happens when you throw a rock into a pond. In this case, the rock would be the Big Bang, and the concentric ripples that result are like a series of waves throughout the universe. Later on, when the first galaxies start to form, they are forming inside space-time that has already been displaced from where it would have been without the wave. So when we observe these galaxies with telescopes, they don't appear to be where we would expect if there had never been a big wave.

One potential issue with this idea is that it might require a big coincidence.

For the universe to appear to be accelerating at the same rate in all directions, we in the Milky Way would have to be near a local center, at the spot where an expansion wave was initiated early in the Big Bang when the universe was filled with radiation.

Temple concedes that this is a coincidence, but said it's possible that we are merely in the center of a smaller wave that affects the galaxies we can see from our vantage point - we need not be in the center of the entire universe for the idea to work."<

posted in Astronomy - 0 replies

Star formation, Big Squeeze?

idea1407 — Fri, 21 Aug 2009 19:16:26 GMT

http://www.space.com/scienceastronomy/090821-stars-trigger.html

>"Big Squeeze Creates New Stars in Cosmic Cloud
By Clara Moskowitz
Staff Writer
posted: 21 August 2009
08:23 am ET

New photos of a cosmic cloud rich with young stars offer tantalizing clues about how those stars came to be.

Scientists recently combined images from the Chandra X-ray Observatory and the Spitzer Space Telescope to zoom in on the cosmic cloud Cepheus B, located in our galaxy about 2,400 light years from Earth.

This cloud of mostly hydrogen gas and dust contains a host of bright young stars whose birth could have been triggered by a nearby massive star outside the cloud. This star, called HD 217086, is bombarding the region with strong radiation. While this energetic flow is likely to have evaporated the cloud's outer layers, it also could have pushed a compression wave into the cloud that may have driven star formation by increasing the density of gas in the cloud's interior.

The new observations, which help astronomers estimate the ages of many of the young stars, support this model of star formation. "<

posted in Astronomy - 1 reply

Martian Meteorite Reveals Past Atmosphere

Hummingbird — Tue, 18 Aug 2009 15:46:06 GMT

http://scienceblogs.com/startswithabang/2009/08/a_meteorite_on_mars.php

From the article:

"Consideration of existing model results indicates a meteorite this size requires a thicker atmosphere," said rover team member Matt Golombek of NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Either Mars has hidden reserves of carbon-dioxide ice that can supply large amounts of carbon-dioxide gas into the atmosphere during warm periods of more recent climate cycles, or Block Island fell billions of years ago."

posted in Astronomy - 0 replies

Nasa assembles Ares test rocket

freetheweed — Mon, 17 Aug 2009 11:08:55 GMT

http://news.bbc.co.uk/2/hi/science/nature/8204921.stm

Page last updated at 09:34 GMT, Monday, 17 August 2009 10:34 UK

NASA assembles Ares test rocket

The US space agency has completed the assembly of its Ares I-X rocket ahead of a test flight scheduled for October.

The Ares I rocket is a key component of Nasa's next-generation space transportation system.

The agency will use Ares I to launch the Orion capsule - the spacecraft to be used for human space missions after the space shuttle retires.

The unmanned test version of the rocket is standing in the vehicle assembly building (VAB) at Kennedy Space Center.

The final segments of the Ares I-X rocket, including the simulated crew module and launch abort system, were stacked together on 13 August on a mobile launcher platform at the VAB in Florida.

Nasa has released images, providing the first look at the 99m (327ft) launch vehicle.

The Ares I-X flight test is targeted for 31 October.

Nasa is scheduled to retire the space shuttle in 2010; the completed Ares-Orion system is not due to fly until 2015 at the earliest.

posted in Astronomy - 2 replies

US probe captures Saturn equinox

freetheweed — Sat, 15 Aug 2009 08:40:34 GMT

http://news.bbc.co.uk/2/hi/science/nature/8201595.stm

Page last updated at 14:10 GMT, Friday, 14 August 2009 15:10 UK

By Judith Burns
Science reporter, BBC News

Raw images of the moment Saturn reached its equinox have been beamed to Earth by the US Cassini spacecraft.

Scientists are studying the unprocessed pictures to uncover new discoveries in the gas giant's ring system.

Equinox is the moment when the Sun crosses a planet's equator, making day and night the same length.

During this time, the Sun's angle over Saturn is lowered, showing new objects and irregular structures as shadows on the otherwise flat plane of the rings.

Saturn's orbit is so vast that Equinox happens only once every 15 Earth years.

At the moment of equinox, the rings turn edge-on to the Sun and reflect almost no sunlight.

This is the first equinox since 1994 and the first time there has been an observer, in the shape of the joint US and European spacecraft, Cassini.

In an email, Dr Carolyn Porco, leader of Cassini's imaging team, said the long-awaited images did not disappoint: "Even a cursory examination of them reveals strange new phenomena we hadn't fully anticipated.

"Over the next week or two, the [Cassini] imaging team will be poring over these precious gems to see what other surprises await us, and, as usual, we will announce what we have found as soon as we can."

Cassini was launched in October 1997 from Florida's Cape Canaveral Air Force Station. It arrived at Saturn in July 2004 to embark on a four-year mission of exploration around the planet and its moons.

The spacecraft is still operating well and has been re-programmed to carry out new tasks. Its current mission is to answer some of the questions raised by its earlier observations.

posted in Astronomy - 4 replies

Kepler proves it can find planets and more

idea1407 — Wed, 12 Aug 2009 18:19:48 GMT

http://tribes.tribe.net/spacesciences/thread/26d15f4f-9a88-49d1-9e31-190fb297aa7d#876f0159-70f7-4937-85da-da9f1480602d

posted in Astronomy - 2 replies

Defying Gravity

freetheweed — Tue, 11 Aug 2009 12:55:58 GMT

A new show on ABC... thought y'all might like it. 3 episodes so far, here's the first:

http://www.hulu.com/watch/86722/defying-gravity-pilot#s-p1-so-i0

The Antares begins its mission to explore the planets in the solar system.

posted in Astronomy - 21 replies