dipper@utastro.UUCP (Debbie Byrd) (12/16/85)
Look for two planets before dawn tomorrow. More on Mercury and Saturn -- right after this. December 16 Saturn and Mercury Two planets that aren't especially easy to see ARE easy to see before dawn now. Saturn and Mercury ornament the southeast shortly before the sun comes up. They're the brightest things low in the predawn sky -- conspicuous now because they appear very near each other. Mercury reaches its greatest elongation on Monday, when it's night for our part of the globe. Greatest elongation indicates the time that Mercury reaches its farthest point from the sun on the imaginary celestial sphere surrounding Earth. It's an event that takes place whether we're facing Mercury and the sun at that time -- or not. This greatest elongation for Mercury happens during our night -- and by the time we see Mercury again, our clocks will show that it's nearly dawn. At dawn, Mercury still will be generally farthest from the sun in our sky -- about 20 degrees from the sunrise point. The presence of Saturn near Mercury is a coincidence -- but a very esthetic one -- one you ought to check out, if you think about it, before the sun comes up on Tuesday. When the world has spun us around to see Mercury and Saturn, we'll be nearly facing the sun as well. It'll be shortly before dawn -- and the two worlds will be hanging there low in the east -- brighter than any thing else in that part of the sky -- and very pretty. And by the way if you miss them on Tuesday, try the next day. The two planets will be drifting apart in our sky -- but they'll remain in the east before dawn all month. Script by Deborah Byrd. (c) Copyright 1984, 1985 McDonald Observatory, University of Texas at Austin