Satellites in a geostationary orbit sit directly over the equator, performing circular orbits approximately 36,000km above the Earth. (This is a special type of geosynchronous orbit.) At this height, the satellite matches the speed and direction of spin of the Earth, so it stays in the same place in the sky. Some weather satellites and communications satellites are placed in this type of orbit because they can provide continuous coverage of a chosen area. Source: UK Space Agency