Quote:
Originally Posted by Astroman
The GPS reciever uses geostationary satellites (up to 24 sats, for military and 12 for domestic)
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They aren't geostationary, as that dictates an equatorial orbit at 1x the sidereal rate, such that a geostationary satellite appears to hover above a single point on the equator.
Off Wikipedia:
Quote:
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The space segment is composed of the orbiting GPS satellites, or Space Vehicles (SV) in GPS parlance. The GPS design calls for 24 SVs to be distributed equally among six circular orbital planes centered on the Earth, and not rotating with respect to the distant stars. The six planes have approximately 55° inclination (tilt relative to the equator) and are separated by 60° RA of the ascending node (angle along the equator). The four SVs in each plane are normally spaced equally, approximately 90 degrees apart.Orbiting at an altitude of approximately 20,000km), each SV makes two complete orbits each sidereal day, so it passes over the same location on Earth once each day. The orbits are arranged so that at least six satellites are always within line of sight from almost anywhere on Earth.
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