DIVISION OF SPACE RESEARCH: RADIO ASTRONOMY AND THE NEW NATIONAL OBSERVATORY*

Abstract

National Radio Astronomy Observatory, Green Bank, W . V a . tOne need only look up at the sun by day or at the stars by night t o understand why astronomy has such a long history as an observational science. Despite some early confusion with respect to the size, shape, and position of our own planet relative t o the sun and stars, man recognized quite early the fundamental role of the sun as a source of light and energy. The moon and brighter planets, which sometimes could be seen by day, moved relative t o the sun and stars, all of which partook of a daily motion from east t o west across the sky. It was further observed that the sun, moon, and planets had cyclic motions northward and southward, and all of these observed events were found t o be related t o things that directly influenced our own activities -the tides, the feeding habits of birds, beasts, and marine life, t h e seasons and t h e spring flowering of the fields oc the autumnal coloring of the forests. Peoples interpreted these things in a variety of ways and reacted accordingly. W e should not b e surprised by the frequent occurrence of sun worshipers or of astrological beliefs and explanations that prevail t o this day. W e should not be surprised that early peoples related groups of s t a r s t o legendary characters or things, real or imagined, that survive t o t h i s day in the familiar constellations. However, we should not let these things blind u s t o the fact that early scientists and engineers put astronomy t o good use. W e should greatly honor and respect Eratosthenes of Alexandria, who in 250 B.C. reasoned that the earth was a sphere and proceeded t o determine its size from the observed difference in elevation of the sun at two stations separated a measured distance along a meridian. Other examples could be cited on t h e early feats of navigation or on the design and orientation or alignment of structures still standing. T h e invention of t h e telescope improved the quality of astronomical observations, but it is important to note that Newton's formulation of modern mechanics was based on a m a s s of observational data that preceded the telescope. In more recent times, as the quality of our observations improved with the development of better telescopes, the photographic plate, the spectrograph, and the photoelectric cell, man's understanding of the universe grew -man now realizes that our sun *This paper, illustrated with slides,