Summer Triangle Constellations

As far as I know there are no turkey constellations in the Butler night sky, but as you go over the river and through the woods for that big Thanksgiving feast there are some other birds soaring in the western sky.

Unfortunately, they have nothing to do with Thanksgiving and are actually summer birds.

Believe it or not, we still have some summer constellations in the evening sky. The same constellations that soared nearly overhead in the warm months of summer are about to make their exit in the west. Our Earth in its orbit around the sun is turning away from the birds of summer.

Two of the birds — the constellations Aquila the Eagle and Cygnus the Swan — are heading for the celestial exits. At the start of each evening these constellations are perched a little above the west-northwestern sky. But, by the start of 2011 they’ll be pretty much at or below the horizon and won’t appear in the evening until next June when they’ll be on the rise in the east.

Just look in the western half of the sky for a triangle of the three brightest stars you can see. This is known as the “Summer Triangle,” and all three of these stars are the brightest in their respective constellations.

The highest one is Deneb — the brightest star in the constellation Cygnus the Swan, making a crash swan dive toward the western horizon. Deneb, a giant star over 1,500 light years away, resides at the tail of the falling celestial fowl. By the way, just one light-year equals almost six trillion miles!

The star on the lower left corner of the Summer Triangle is Altair, positioned at the heart of Aquila the Eagle. Most of the rest of this constellation shaped like giant sideways diamond may be a little hard to see since it’s so low in the sky.

The brightest star of the Summer Triangle is Vega, on the lower right corner. The light we see originally left the star about the time Ronald Reagan became President in 1985.

Vega is also the brightest star in the tiny constellation Lyra the Lyre, which is an old fashioned harp. Look for four faint stars that you can barely see with the naked eye to the left of Vega that form a small parallelogram and that’s supposed to outline a diminutive harp in the sky.

Actually, up until the time of the American Revolution, all three of the summer triangle constellations were seen as birds. Lyra the Harp was actually pictured as an eagle clasping a small harp in its beak.

In fact, more than 2,000 years ago ancient India saw what we see as Lyra the Harp as a Vulture. Many Arabic cultures about the same time saw the constellation as a desert eagle.

Make sure you give thanks this week to everything and everybody you love on this earth and all the treasures in the starry skies. While you’re gazing in the heavens after you down that Thanksgiving turkey, fighting off the sleepy effects of the tryptophan, look to the west and say a final farewell to summer, or at least the birds of summer, all three of them. Bye Bye birdies!

Celestial Huggings this week: Sunday night the waning full moon will be hanging out just below and to the left of the wonderful Pleiades star cluster in the eastern evening sky.

The Pleiades, otherwise known as “The Seven Little Sisters,” is an open star cluster of over a hundred young stars about 400 light years away. With the naked eye it looks a little like a miniature Big Dipper. Most people can see six stars but if you’ve kept up on your carrots you may see seven. How many can you see?

Mike Lynch is an amateur astronomer and professional broadcast meteorologist for WCCO Radio in Minneapolis and is author of the book, “Pennsylvania Starwatch,” available at bookstores and at his website www.lynchandthestars.com