dipper@utastro.UUCP (Debbie Byrd) (06/04/85)
The glittering Milky Way is returning to the evening sky. More -- after this. June 4 The Return of the Milky Way The Milky Way is a spiral galaxy -- round and flat like a pancake. It's about a hundred thousand light-years wide -- and about a thousand light-years thick -- made of hundreds of billions of stars. Since our sun and planets move inside the flat plane of the Milky Way, we see more stars when we look sideways into the plane than when we look up and out of it. In a dark country sky, in late summer, we've got the best view of the galaxy in the evening. Then our evening sky faces the star-rich center of the Milky Way -- and we see a ribbon of densely packed stars stretching between two horizons. The Milky Way appears so faraway and hazy that some people mistake it for a cloud. That'll be the view in late summer, when Earth has moved a little farther around the sun -- last month, the plane of the Milky Way was nearly parallel with our horizon in the evening hours. So the starry ribbon of the Milky Way wasn't visible in our sky in the evening last month -- instead, it lay all around us, hidden in the haze above the circle of the horizon. This month, the Milky Way is beginning to edge up over the eastern horizon in the evening hours. We don't yet see the richest portion of the galaxy -- the galactic center -- until the middle of the night. But those in the country may make out a hazy band in the east in mid-evening -- really myriad stars in the plane of our own Milky Way. Script by Deborah Byrd. (c) Copyright 1984, 1985 McDonald Observatory, University of Texas at Austin