Satellite gravimetry
Retrieves time-variable gravity-field and mass-change signals by tracking changes in distance between two co-orbiting satellites, as in GRACE and GRACE-FO.
Satellite gravimetry is the method used when the target is mass redistribution rather than surface appearance. A pair of satellites follows the same orbit; changes in the pull of Earth's gravity alter their separation, and precision inter-satellite ranging turns those distance changes into monthly gravity-field and equivalent-water-height maps. It resolves basin-to-global mass signals such as ice-sheet mass, groundwater and terrestrial water storage, and ocean-mass sea-level components. It is weak for local detail: spatial resolution is coarse, leakage corrections matter near coasts and small basins, and the retrieval depends on geophysical background corrections.
- K-band Ranging Instrument (KBR)
via GRACE
KBR microwave inter-satellite ranging demonstrated on GRACE and reused on GRACE-FO for satellite gravimetry.
- SuperSTAR Accelerometer
via GRACE
Onboard electrostatic accelerometers support GRACE and GRACE-FO satellite gravimetry by observing non-gravitational acceleration for force correction.
- GRACE-FO Laser Ranging Interferometer (LRI)
via GRACE-FO
GRACE-FO LRI demonstrates laser inter-satellite ranging for satellite gravimetry.
None on record.
Determines the static gravity field and fine geoid by measuring gravity gradients directly with an onboard gradiometer, as demonstrated by GOCE.
- [1]GRACE-FO Mission Overview, NASA/JPLagency doc2026-06-08Describes paired GRACE-FO satellites, approximately 220 km separation, precise microwave ranging, accelerometers, and monthly gravity-field maps showing mass movement.
- [2]Gravity Recovery and Climate Experiment (GRACE), NASA/JPLagency doc2026-06-08Mission overview: GRACE measured gravity changes with twin spacecraft and supported ice mass, sea level, groundwater, drought, and solid-Earth applications.
- [3]Applications and Challenges of GRACE and GRACE Follow-On Satellite Gravimetrypeer reviewed2026-06-08Review of GRACE/GRACE-FO satellite gravimetry applications and limitations for cryosphere, hydrology, oceans, and solid Earth.
Edited from public sources. Last reviewed date pending by SpectraWorks editorial. See the data dictionary for field definitions.