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Summer Triangle: Altair and Aquila the Eagle


Tonight for July 17, 2014

In the east after dark on these July evenings, look near the horizon for Altair, the brightest star in the constellation Aquila the Eagle. This is the bottom star of the Summer Triangle; that is, it’s the last of these three bright stars to ascend over the horizon.

The Great Rift of the Summer Milky Way passes through the Summer Triangle, between the stars Vega and Altair. In dark skies in late July and the first two weeks of August, you can see rich star fields with your binoculars on both sides of the Great Rift.

In modern western culture, Altair is probably best known for being the home star system of the aliens in the 1956 science fiction film Forbidden Planet. But in Asian cultures, Altair and the star Vega figure in one of the most beautiful of all stories in the night sky. In Japan, for example, Vega is sometimes called Tanabata (or Orihime), a celestial princess or goddess. She falls in love with a mortal, Kengyu (or Hikoboshi), represented by the star Altair. Read the rest of the story here.

The whole Summer Triangle area is great to observe with binoculars or in dark skies with just your eyes. If you like finding hidden pictures, get set to find a Coathanger, the North American Nebula (NGC7000): and Ring Nebula (M57).

Great Rift of Milky Way passes through the constellation Cassiopeia and the Summer Triangle. Click her for a larger photo

Our Summer Triangle series includes:
Vega and its constellation Lyra
Deneb and its constellation Cygnus
Altair and its constellation Aquila

July 2014 guide to the five visible planets

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