dipper@utastro.UUCP (Debbie Byrd) (07/30/84)
Landsat 1 made it possible to scrutinize Earth from outer space. More about it -- when we come back. July 23 A Satellite to Save the World On today's date in the year 1972, the first Landsat was launched. Landsat 1 systematically surveyed Earth's surface -- to study the health of its crops and the potential of its land and oceans. By the time the second Landsat was launched, in 1975, NASA administrator James Fletcher said that if he had to chose one space-age development to save the world, it would be satellites like Landsat. The first Landsat was placed in a near-polar orbit that enabled the satellite to circle the Earth fourteen times every day. It could view any point on the Earth, except for small areas around the poles. What's more, its orbit was such that every eighteen days, it would view the same spot on Earth's surface at the same time of day. Each pass let the craft's cameras view an area of land or water more than a hundred miles wide. The Landsats were originally known as ERTS, for Earth Resources Technology Satellites. NASA reconsidered this name in the early 1970s, and thought about calling them "Earth satellites" or "Survey satellites" or even "Ceres satellites" for the ancient Greek goddess of the harvest. They finally got the name Landsat after another satellite series -- meant to study the oceans -- was called Seasat. There were three Landsats launched in the 1970s -- a fourth launched early in this decade -- and since this past spring, there's also a fifth landsat which still peers down at Earth from orbit -- and sends back invaluable data on the Earth's resources. Script by Deborah Byrd. (c) Copyright 1983, 1984 McDonald Observatory, University of Texas at Austin