dipper@utastro.UUCP (Debbie Byrd) (04/20/85)
No matter where you live, the word zenith describes the point directly over your head. More astronomical terminology -- coming up. April 20 Zenith At any given moment, the sky looks different to people standing on different parts of the globe. But no matter where you are, there are some astronomical words that apply to the sky -- words that can help you get to know it. For example, no matter where you are, you can look straight up at what astronomers call the ZENITH -- the point directly over your head. People at the north pole see the pole star at about their zenith -- while people at the equator don't see the pole star at all. But they do see the SUN at their zenith -- a blazing light directly overhead at noon -- twice a year -- at the equinoxes. Meanwhile those people at the north pole again never see the sun anywhere near their zenith. So the zenith is the point directly over your head -- a point that's different for everyone -- depending on the season, the time of day, and on where you are on the Earth. If you draw an imaginary line through your zenith -- connecting due south to due north -- you have a line called the meridian bu astronomers -- a line that divides your sky into two equal halves. Stars reach their highest points in the sky when they're on the meridian. By the way, there's also a word -- nadir -- for a point we never see. The nadir is the point directly beneath your feet -- all the way through the globe of the Earth -- the overhead point in the sky for people opposite you on the globe. Script by Deborah Byrd. (c) Copyright 1984, 1985 McDonald Observatory, University of Texas at Austin