dipper@utastro.UUCP (Debbie Byrd) (09/29/84)
Happy autumn equinox! We talk more about this hallmark of the year -- right after this. September 22 The Autumn Equinox If you lived at Earth's equator, you'd see the sun directly overhead at noon today -- because today is the equinox, when the sun appears to cross the celestial equator, moving from north to south. The exact moment of the equinox takes place at 2:34 p.m. Central Daylight Time -- that's our local time here in Austin, Texas. The equinox marks the beginning of spring for the southern hemisphere -- and the beginning of autumn for those of us who live north of the equator. The sun has been and will continue to cross the sky on paths that lie lower and lower in the south. Meanwhile, people "down under" see the sun's path push higher and higher, as days lengthen and temperatures slowly rise. The equinox is a good day to do something very useful for stargazers. It's a good day for finding the directions due east and due west from your house or favorite spot to observe heavens. That's because the sun rises due east at the equinox -- and sets due west. If you've got a favorite place for watching the sky, just situate yourself there at sunset. Locate some terrestrial landmarks -- trees or buildings, maybe -- and then wait for the sun to go down. If you always come back to that exact same place to observe, you'll be able to use your earthly landmarks to show you where due west is located -- that's a very helpful bit of knowledge when you're using a star chart, for example. The direction east, of course, is just opposite that -- behind your back as you face due west. Script by Deborah Byrd. (c) Copyright 1983, 1984 McDonald Observatory, University of Texas at Austin