An Etymological Dictionary of Astronomy and Astrophysics

A coordinate positioning tool, using a combination of satellites
that can rapidly and accurately determine the → latitude, → longitude, and the → altitude of a point on or above the Earth’s surface. The GPS is based on a constellation of 24 Earth-orbiting satellites at an altitude of about 26,000 km. The system is a direct application of the thories of → special relativity and → general relativity.

See also: → global; → positioning; → system.