Orion's Last Call

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One of the most beautiful constellations is putting in its final evening-sky appearance of the season over the next couple of weeks. It'll soon disappear in the Sun's glare. The next time we see it after that, it'll be in the morning sky shortly before sunrise.

The constellation is Orion, the hunter. Look for it low in the west-southwest in early to mid evening. Its most promiment feature is a short line of three stars called Orion's Belt. The Belt appears almost parallel to the horizon, and sets about three hours after sunset.

Below and to the left of the Belt, look for Rigel, the constellation's brightest star. It has a brilliant blue-white color, although it may look a bit dull right now because Rigel is so low in the sky. Rigel is a supergiant star. That means it'll live a brief but spectacular life, then die an even more spectacular death -- a titanic explosion called a supernova.

Orion's most famous star is Betelgeuse, which stands above and to the right of the Belt. It, too, is a supergiant, but a red one, not a blue one. That indicates that Betelgeuse is farther along in its evolutionary path than Rigel, and probably closer to that big end-of-life explosion.

Look for these two future exploding stars low in the western sky in early evening the next few nights. Rigel will disappear in the evening twilight within a few days, with Orion's Belt following a few days later, and Betelgeuse toward the middle of May.

Script by Damond Benningfield, Copyright 2004, 2008

For more skywatching tips, astronomy news, and much more, read StarDate magazine.