(
Medium-
Earth
Orbit) A communications satellite in orbit roughly from 1,600 to 15,000 miles above the earth. Revolving around the earth, MEO orbits are higher than low-earth orbit (LEO) and lower than geostationary (GEO) satellites. Widely used for navigation systems such as GPS and GLONASS, MEO satellites can take from two to 24 hours to orbit the earth. See
LEO,
GEO,
HEO and
GPS.