Mondo Knows Facts
GPS relies on a constellation of at least twenty-four active satellites
The Global Positioning System calculates positions using atomic clock signals from medium Earth orbit
Developed by the United States Department of Defense in 1973, GPS became fully operational in 1995 with twenty-four satellites orbiting roughly 20,200 kilometres above Earth. Receivers calculate geographical position, altitude, and precise time by measuring microsecond signals from multiple satellites simultaneously. Relativistic corrections are applied to compensate for satellite orbital speed and gravity.
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Tags: gps, satellites, navigation
GPS relies on a constellation of at least twenty-four active satellites: the short answers
- Where does this come from, and can I check it?
- The Global Positioning System calculates positions using atomic clock signals from medium Earth orbit. The figure is taken from GPS.gov, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
- Is this really a technology fact?
- Yes. It sits on the Technology shelf, one of 1,090 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
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