Moon and Scorpius
The almost-full Moon takes aim at the head of the scorpion tonight -- three bright stars that form a diagonal line to the Moon's left. From top to bottom, they're known as Beta, Delta, and Pi Scorpii.
There's much more to these stars than meets the eye. Each of them is actually a system of at least four stars. And the systems are probably related. They're members of a large group of stars that formed from a giant cloud of gas and dust.
Many of these stars are supergiants -- stars that are much bigger, heavier, and brighter than the Sun.
Beta Scorpii, for example, consists of at least five stars, and at least four of them are supergiants. They're thousands of times brighter than the Sun, making the system easily visible across 500 light-years of space.
To the lower left of the scorpion's head is its orange heart -- the star Antares. It's a supergiant, too -- part of the same group as the others. More about Antares and the Moon tomorrow.
These stars not only share a common birth, they'll share a common death. Supergiants live bright but short lives -- millions of years compared to billions of years for stars like the Sun. And when they're done, they'll go out with a bang -- each one will blast itself to bits as a supernova.
Millions or billions of years in the future, some of their scattered remains will be incorporated into new stars -- continuing the cycle of stellar birth and death in the scorpion.
Script by Damond Benningfield, Copyright 2009
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