Satellite geodesy
Satellite geodesy is the measurement of the form and dimensions of the Earth, the location of objects on its surface and the figure of the Earth's gravity field by means of satellite techniques. In other words, geodesy by means of satellites. It belongs to the broader field of space geodesy, which also includes such techniques as geodetic very long baseline interferometery VLBI and lunar laser ranging.
Traditional astronomical geodesy, which includes astronomical positioning, is not commonly considered a part of satellite geodesy. Also surveying by GPS has become so commonplace that it is less and less considered part of satellite geodesy.
Satellite geodetic measurement techniques
- Geodetic use of global positioning satellite systems (GPS, GLONASS, Galileo)
- Laser ranging to satellites (SLR)
- Synthetic aperture radar (SAR) interferometry from orbit
- Satellite radar altimetry (mostly over oceans)
- Satellite laser altimetry (over land)
- Satellite orbital tracking for determining the Earth's gravitational field; e.g., CHAMP
- Satellite gradiometry (measuring the gravity gradient from orbit); GOCE
- Satellite-to-satellite tracking; GRACE.