Sadr

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Cygnus, the swan, soars high across the sky tonight, immersed in the glow of the Milky Way. Its brightest stars form a cross. The long arm of the cross represents the swan's body and neck, while the short arm outlines its wings. The swan aims toward the southwest.

The star at the intersection of the two arms is called Sadr, an Arabic name that means "the hen's breast." It's a remarkable star in a remarkable region of the sky.

Sadr is a supergiant, so it's much bigger and hotter than the Sun. It's also thousands of times brighter than the Sun, so it's easily visible to the unaided eye even though it's about 1500 light-years away.

Sadr and the other stars of Cygnus are embowered in the Milky Way -- the combined glow of millions of stars in the disk of our Milky Way galaxy. But the Milky Way splits into two bands inside Cygnus, separated by a dark lane that runs parallel to the swan's body. This lane is caused by clouds of interstellar dust, which block the light from the stars behind them, just as clouds here on Earth block the view of the sky beyond.

Use binoculars or a telescope to scan between Sadr and the star that represents the swan's head for the Cygnus Star Cloud -- thousands of stars swarming across the sky. It's one of the richest star fields in the galaxy.

Look for Sadr, the star at the heart of the swan, high overhead around 9 or 10 o'clock, and nosediving down the western sky during the rest of the night.

Script by Damond Benningfield, Copyright 2001, 2004, 2008

For more skywatching tips, astronomy news, and much more, read StarDate magazine.