dipper@utastro.UUCP (Debbie Byrd) (12/09/84)
Some kinds of astronomy can be done in the daytime. More -- in a minute. December 9 Twenty-four Hour Astronomy The classic idea of an astronomer is someone bent over a telescope in the middle of the night -- peering at the heavens. But astronomy is a twenty-four hour science. Until this century astronomers studied just the VISIBLE light of stars -- the light we see with our eyes. But visible light is only a tiny portion of the electromagnetic spectrum. In this last century astronomers discovered that stars radiate a whole array of electromagnetic energy. Modern astronomers try to study the whole spectrum -- as the various types of energy radiations tell us different things. Some of these other kinds of energy can be collected by Earth-based telescopes even when the sun is in our sky. For instance, radio astronomers observe through the day as well as the night -- pointing their antenna telescopes toward celestial radio sources. They then usually want to compare their findings with those of optical astronomers -- to see if there is a visible light source at the same spot in the sky that's emitting the radio waves. There are some astronomers who find that daytime is the ONLY time for studying a certain average star! But this one holds a very special interest for us, as the star we orbit -- our sun. Even as telescopes are placed in space and larger ones are constructed here on Earth's surface, there's still not enough time in the day -- or the night -- for astronomers to collect all the information needed to provide answers to our ever-growing number of questions about the universe. Script by Diana Hadley. (c) Copyright 1983, 1984 McDonald Observatory, University of Texas at Austin