Why are satellites sometimes put into polar orbits?
Satellites are placed in a variety of orbits with different inclinations to the equator to carry out specific activities. Low-inclination orbits span only a narrow range of latitudes and can include geosynchronous satellites that remain fixed in the sky over a specific longitude. Polar orbits can be made to scan the entire earth's surface and are useful for geographic surveying, weather monitoring and espionage. As the satellite loops around from north to south, the earth rotates underneith it by a fixed amount of longitude per orbit. Over the course of several days or weeks, the entire surface can be photographed or studied.
Copyright 1997 Dr. Sten Odenwald
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