dipper@utastro.UUCP (Debbie Byrd) (01/10/86)
The brightest star in the night sky is Sirius -- now in the south each evening. More -- when we come back. January 10 The Dog Star Sirius You can always recognize at least one star in the winter sky. That's Sirius, the brightest star in the night sky. If you want to see Sirius, look in the south in the evening. Sirius belongs to the constellation Canis Major, the Greater Dog -- a prominent grouping of stars located mostly below Sirius in the south. The ancient Greek stargazers didn't see a dog here -- they were concerned only with Sirius itself, the night sky's brightest star. Australian aborigines also considered the star Sirius a constellation unto itself -- the star was called their Eagle. It wasn't until later that the Romans identified the stars near Sirius with a dog. It was believed in those days that the intense heat of summer drove dogs mad. Sirius is sometimes called the Dog Star, and from this star comes our expression "dog days" as applied to the hottest part of summer. In the heat of the summer, Sirius is located behind the sun along our line of sight. Then it rises the same time the sun does each day, and travels with the sun across the dome of the sky. The Romans believed that the combination of Sirius and the sun actually caused the hot weather. They used to sacrifice a dog to Sirius once each year to prevent this "heat star" from scorching their crops. Again, you can easily see Sirius in the south now each evening. Only the planet Jupiter shines more brightly among the stars -- and Jupiter now is setting shortly after the sun. After Jupiter is gone, Sirius appears as the brightest star in the sky. Script by Deborah Byrd. (c) Copyright 1985, 1986 McDonald Observatory, University of Texas at Austin