dipper@utastro.UUCP (Debbie Byrd) (08/09/85)
Since the space age began, a new potential problem has arise -- that of debris in orbit around the Earth. More -- in a minute. August 9 Orbital Debris Our planet Earth has some debris surrounding it -- sometimes meteoroids once in orbit around the sun -- that may have encountered our world -- then gone into orbit around Earth. But, since the dawn of the space age, debris also has been left in Earth-orbit by people. This debris may be satellites that are no longer functioning -- or the upper stages of rockets used to launch satellites. Also, smaller pieces like antennas sometimes break off a satellite -- to pursue their own paths around the Earth. At last count, there were more than five thousand objects orbiting the Earth. That's five thousand known objects -- catalogued by NORAD -- the North American Defense command. With radar, NORAD is able to track objects five inches or larger that are in low-earth orbit, about 250 miles above the surface of our planet. The space shuttle and many satellites orbit in this general region. Also, future space stations of the U.S. and Soviet Union are likely to be placed in this orbit. The trouble is that everything in orbit is moving at more than FIVE MILES PER SECOND -- so that any collisions could easily cause catastrophic damage, even if the colliding object is as small as a grain of sand. Plus any orbital explosions or collisions make the situation much worse because of all the fragments they release. According to the experts, space debris is just beginning to become a problem. But it's already being explored since cleaning up the debris will be difficult -- and costly. Script by Diana Hadley, Deborah Byrd, and Harlan Smith. (c) Copyright 1984, 1985 McDonald Observatory, University of Texas at Austin