medium Earth orbit

Medium Earth Orbit (MEO), sometimes called Intermediate Circular Orbit (ICO), is the region of space around the Earth above low Earth orbit  and below geostationary orbit . The most common use for satellites in this region is for navigation, such as the GPS , Glonass  and Galileo  constellations. Communications satellites that cover the North and South Pole are also put in MEO.The orbital periods of MEO satellites range from about two to 12 hours. Telstar, one of the first and most famous experimental satellites, orbited in MEO.
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