Bellatrix

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Harry Potter fans may boo or hiss a bit when they hear its name, but one of the stars of Orion is nothing to sneer at. It's one of the hottest stars in the neighborhood, and one of the brightest, too.

Bellatrix forms Orion's right shoulder. As night falls, it's directly above Orion's Belt and to the right of the hunter's other shoulder, bright orange Betelgeuse.

The name means "the female warrior," after the Amazons of Greek mythology. And the star itself is indeed a powerful one. Its surface is tens of thousands of degrees hotter than the surface of the Sun. The star is several times larger than the Sun, too. The combination of size and temperature makes Bellatrix shine thousands of times brighter than the Sun.

The key to that power is the star's mass -- about eight or nine times that of the Sun. Heavier stars burn through the nuclear fuel in their cores in a big hurry, so they produce far more energy than stars like the Sun.

Bellatrix is probably nearing the end of its life. It's not massive enough to explode as a supernova, so its fate most likely is similar to the Sun's. It will cast its outer layers into space, briefly surrounding itself with a colorful bubble of hot gas. When the gas dissipates, all that will remain is the star's hot, dense core: a white dwarf. This faint cosmic ember will be far too faint to see from here on Earth, so the hunter will lose his strong right shoulder.

Script by Damond Benningfield, Copyright 2009

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