dipper@utastro.UUCP (Debbie Byrd) (11/20/86)
Look for Venus and Mercury in the predawn sky tomorrow. More -- after this. November 20 Venus and Mercury Earlier this month, both Venus and Mercury passed between the sun and Earth. Since they move faster than Earth in orbit, they rushed between our world and the sun like race horses running on an inside track. Around then, they were invisible in Earth's sky. Looking toward them meant looking in the direction of the sun. But now Venus and Mercury have begun to pull ahead of Earth in their smaller orbits around the sun. They're pulling away from our line of sight to the sun -- becoming easier to see in our sky. You can see them, if you get up before dawn. Venus is much brighter than Mercury, not only because it's closer to Earth -- but also because it's covered with thick clouds that are good at reflecting sunlight. Venus is now low in the east before dawn -- the brightest thing in that part of the sky. As the months pass, and as Venus continues to flee ahead of Earth in orbit, we'll see it rise higher in the predawn sky. Mercury is fainter -- but if you look and see Venus, you might be able to find Mercury, too, to the other world's lower left. Like Venus, Mercury will appear to move farther from the sun each day. But because its orbit is smaller than that of Venus -- because it orbits closer to the sun -- Mercury will turn and head back into the dawn again long before Venus does. We'll see Venus up before dawn until next summer. Meanwhile, Mercury will be there for only about a month before it turns the corner ahead of Earth in orbit -- and disappears again into the sun's glare. Script by Deborah Byrd. (c) Copyright 1985, 1986 McDonald Observatory, University of Texas at Austin