Future Blasters
Orion, the hunter, climbs back to prominence this month. Right now, he's in good view in the east by 9 o'clock. Look for the line of three bright stars that marks Orion's Belt standing almost straight up from the horizon. The bright orange star Betelgeuse is to the Belt's left, with the slightly brighter blue star Rigel the same distance to its right.
Someday, the cores of these two stars will collapse, and their outer layers will rebound, setting up shock waves that will blast the stars to bits as supernovae.
Watching stars just before they explode can help astronomers understand the processes that power supernovae. It can also help tie together the theories of how such stars die and how they live.
Unfortunately, there's no way to know when a star is about to explode. So after a supernova flares to life, astronomers try to find pictures of the star before the explosion.
The search is complicated by the fact that all of the supernovae that astronomers have seen in the last few centuries are in galaxies outside the Milky Way. It's difficult to pick out an individual star from the billions of other stars in another galaxy.
So far, astronomers have found about a half-dozen stars that later became supernovae. A Texas astronomer is looking for more. The search may help astronomers turn back the clock, and look at ticking timebombs before they blow up.
We'll talk about the aftermath of an explosion tomorrow.
Script by Damond Benningfield, Copyright 2006
For more skywatching tips, astronomy news, and much more, read StarDate magazine.
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