During the late evening hours the famous Summer Triangle is high in the eastern sky. The Triangle consists of three of the brightest stars in the sky, each the brightest star in its own constellation and serving as a guide to the Milky Way.

The brightest is the bluish-white star Vega, in Lyra the Lyre. Next in brightness is yellow-white Altair in Aquila, the Eagle. Finally there is white Deneb, in Cygnus, the Swan. From our viewpoint, Vega appears twice as bright as Altair and more than three times brighter than Deneb. But sometimes things are not always what they seem.

Brilliant Vega pales in comparison with Deneb, however, one of the greatest supergiant stars known.

Deneb's distance measures 1,467 light years from Earth with a luminosity computed to be more than 60,000 times that of our Sun. But because its light takes nearly 15 centuries to reach us, Deneb merely appears as a fairly conspicuous but by no means particularly notable star.

With the bright Moon now pretty much out of the way, there is no better time to observe the beautiful summer Milky Way.

With a good pair of binoculars or a telescope you can now observe some of the millions of sparkling little stars that make up this glowing, irregular belt of luminosity. It appears to arch from the north-northeast to the south-southeast, with its brightest and most spectacular region running across the Summer Triangle and beyond, toward the south-southeast horizon.

There appears to be a great black rift dividing it into two streams, beginning with Cygnus and extending down toward the south. Also in Cygnus is the black void known as the Northern Coal Sack. This Coal Sack and the Rift are not holes in the Milky Way, but rather are vast clouds of dust "floating" out in interstellar space and presenting a solid and impenetrable curtain between us and the more distant stars.

There have been many stories, myths and legends told about the Milky Way in many different cultures. A poignant Japanese legend actually plays out in the sky this week.

The star Vega represented Orihime, who produced brilliantly colored fabrics. Across the "Heavenly River" (the Milky Way), Altair represented the cowherd Kengyu.

After meeting each other they received divine permission to marry, whereupon both abandoned their occupations. This angered the gods, who separated them and sent them back to their original jobs on opposite sides of the heavenly river. The couple however, received permission from the gods to get together for one night each year. That special night is July 7, but only if the sky is clear and only if the imagination is grand; the stars, of course, don't actually get any closer together than on any other night.

Still, the evening of July 7 has evolved into a young-people's holiday in Japan called Tanabata. Prayers are then offered for clear skies so that Orihime and Kengyu, the star-crossed lovers can be reunited.

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