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Massive stars lead short, yet spectacular lives, as a new multi-wavelength image from NASA's Chandra X-ray Observatory and optical telescopes shows. X-ray (blue) and optical (red and green) data reveal dramatic details of a portion of the Crescent Nebula, a giant gaseous shell of gas created by powerful winds blowing from the doomed massive star HD 192163. After only 4.5 million years (one-thousandth the age of the Sun), HD 192163 began its headlong rush toward a supernova catastrophe. First, it expanded enormously to become a red giant and ejected its outer layers at about 20,000 miles per hour. Two hundred thousand years later -- a blink of the eye in the life of a normal star -- the intense radiation from the exposed hot, inner layer of the star began pushing gas away at speeds in excess of 3 million miles per hour! When this high-speed "stellar wind" rammed into the slower red giant wind, a dense shell was formed. In the image, a portion of the shell is shown in red. The force of the collision created two shock waves: one that moved outward from the dense shell to create the green filamentary structure, and one that moved inward to produce a bubble of million-degree Celsius X-ray-emitting gas (blue). The brightest X-ray emission is near the densest part of the compressed shell of gas, indicating that the hot gas is evaporating matter from the shell. HD 192163 will likely explode as a supernova in about 100,000 years. This image enables astronomers to determine the mass, energy, and composition of the gaseous shell around this pre-supernova star. An understanding of such environments provides important data for interpreting observations of supernovas and their remnants. Related Links Chandra X-ray Observatory Center SpaceDaily Search SpaceDaily Subscribe To SpaceDaily Express 
Waiting For A Supernova
Paris - Sep 24, 2003A team of European astronomers is using the NASA/ESA Hubble Space Telescope to look back in time. They have imaged the spiral galaxy NGC 3982 and hundreds of other galaxies in the hope that one of the millions of stars in these images will some day explode as a supernova. They can then look back and pinpoint the exact star that has exploded. Only two such supernova "mother stars" have ever been identified. |
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