The Celestial Bridge

Flowing across the sky from Cassiopeia in the north-east to Sagittarius in the south is the summertime Milky Way. the summertime Milky Way. It certainly looks like a stream of milk in the sky, and, since the Greek word for milk is "gala,"it came to be known as the Milky Way Galaxy.

The ancient Chinese tell of the weaver girl She-niu and her lover, a peasant shepherd-boy. A small river flowed between their lands, and they could often visit one another. As the years passed, however, the stream grew into a mighty torrent, and they were forever separated. They grew old, forever loving, forever faithful. The two died longing for one another.

To preserve this love, they were transported to the sky: She-niu as the star Vega and the shepherd boy as Altair, separated by the Milky Way. Once a year, though, a flock of magpies forms a celestial bridge so the lovers can join.

It may be just a coincidence, but any one of us, using the simplest pair of binoculars, panning from Vega to Altair, will see -- not a milky stream, but thousands of stars, looking like -- a flock of magpies.

Thatıs just what Galileo first saw four hundred years ago, with his primitive telescope. What men and women had always called the Milky Way was really just a band of thousands of stars too dim to be seen individually without optical aid.

We know now that what we call the Milky Way is just one of the spiral arms of our home galaxy, a grand pinwheel of hundreds of billions of stars.

This arm splits as it passes through the Northern Cross. Called the "Great Rift," this split is caused by enormous clouds of gas and dust obscuring the more distant stars in the Milky Way. These obscuring clouds, called "dark nebula," are found in every part of the sky.

(06/27/07)