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View Full Version : Discussion: A Supernova that Won't Fade Away



Fraser
2005-Jul-21, 04:35 PM
SUMMARY: Supernovae are powerful stellar explosions that flare up brightly and then slowly fade away. But not always. One supernova, that exploded in 1979, is blazing as brightly in X-rays as it did when it was first discovered. The discovery was made using the ESA's XMM-Newton space telescope. Scientists speculate that a powerful solar wind is smashing into previously ejected material, heated it up until it glows brightly. This is like a powerful light illuminating the whole area, and allowing the astronomers to study the whole area for years and see how it changes over time.

View full article (http://www.universetoday.com/am/publish/old_supernova_in_M100_galaxy.html)

What do you think about this story? Post your comments below.

antoniseb
2005-Jul-21, 05:38 PM
It's interesting that this bright object is telling us some things we don't normally learn about former stars. The article said that it was unknown just why this object is still so bright in xrays. I'd have liked to have known more about what they've considered and dismissed as reasons. Could it be that the star was a close binary, and the remnant is now accreting from the companion? It seems like that would be one of the first ideas they'd try to rule out, but it wasn't mentioned.

lswinford
2005-Jul-21, 07:44 PM
I seem to recall that x-rays are the product of matter falling upon a neutron star or at some stage of the collapse of matter into a vortex about a black hole.

The visible light of this star is diminishing, but wouldn't the x-rays be evidence of something comparable to a long, steady rain as matter falls back upon the star from the star's massive gravity?

Besides, 16,000 years is still a pretty small blip of time to such an old universe, or so I suspect.