Posted on 03/09/2008 11:11:33 PM PDT by neverdem
Thanks to a lucky break and an overactive galaxy, astronomers have for the first time caught a massive star in the act of exploding. An X-ray outburst recently recorded by NASA's Swift satellite suggests that researchers began viewing the violent demise of a star in the galaxy NGC 2770 just a few seconds after the first X rays arrived at Earth, and hours before the first visible-light fireworks.
Most supernovas aren't identified until they generate an outpouring of visible light, long after key information about the size and other properties of the collapsing star has vanished. The new finding suggests that astronomers using wide-angle X-ray telescopes could routinely witness the very beginnings of hundreds of supernova explosions each year, suggest Alicia Soderberg and her colleagues in an online posting.
Astronomers have previously observed the immediate aftermath of a related class of stellar explosions, the demise of massive stars that are signaled by gamma-ray bursts, the most powerful eruptions in the universe. But in each of the four cases for which researchers have firmly established the link between a supernova and a gamma-ray burst, the bright visible-light afterglows of the bursts hide the information-rich early emissions from the supernovas, Soderberg's team notes.
Early, X-ray signs of supernovas have been predicted for 4 decades but never before been found.
On Jan. 9, Soderberg and her colleagues were using an X-ray telescope on Swift to study a supernova in NGC 2770 that had been discovered 10 days earlier. Just as Swift began observations of this supernova, it recorded a fresh spike of X rays from another region in the galaxy that lasted for about 7 minutes. On Jan. 11, using the Gemini North telescope on Hawaii's Mauna Kea, Soderberg and her colleagues identified the visible-light fingerprint of the new supernova, now dubbed...
(Excerpt) Read more at sciencenews.org ...
They were emitted first. I don't know why the visibile light was emitted later. I'm not an astrophysicist.
:’)
I agree, we should make the ozone layer very thick.
bump
Yeah, I wonder about those “dark spots” in space, the ones that light doesn’t shine through and which do not seem to have enough mass (thus weak gravity) to bend light around them? Could be Dyson constructs, yes?
no (hopefully not :)
can you imagine, the size of those spheres...at those distances? *whistle*
They would be very old, constructed in the earliest eons of the universe. If the stars inside had supernovaed, they would of course shredded.
paging: Carl ("millions upon millions of light years ago....") Sagan.
it just depends "on where" you stand.
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