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>"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. "<