Tuesday, July 17, 2012

SUMMER TRIANGLE

During the heart of summer three bright stars make a large, noticeable triangle in the sky (Vega, Deneb, and Altair). This Summer Triangle can be seen even from the most light polluted skies. Although it makes a nice urban constellation, each star is really part of its own heavenly picture.

High up in the sky is bright, blue Vega. Vega is where the aliens from the movie Contact were calling from. Not too far away (only 25 light years), Vega is part of the constellation called Lyra the Harp. Lyra looks like a small parallelogram.

Down and to the left is dimmer star called Deneb. Deneb is a whopping 3,000 light years away - making it the farthest star you can see with the naked eye. This is the tail of the swan, the constellation Cygnus - and these stars actually look like a swan with a stretched out neck going to the right and wings up and down. Cygnus is also called the North Cross because, well, it looks like a cross jutting into the center of the Summer Triangle.
To the right is bright, white Altair. Altair is the head of the constellation Aquila, the Eagle. Although the Eagle might be tough to imagine from the stars, Altair is easy to find because it has two dimmer stars bracketing it.  And it's so bright because it's only 17 light years away.

Look for the Summer Triangle hight in the eastern sky after sunset - closer to overhead later at night.
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