Geocenter

The geocenter is the center of mass of the entire Earth system, including the solid Earth, oceans, and atmosphere, and serves as the origin of global geodetic reference frames like the ITRF. It can be measured using satellite techniques such as Satellite Laser Ranging (SLR), GNSS, and GRACE/GRACE-FO gravity observations, which detect mass redistribution and center-of-mass shifts. Monitoring geocenter motion is essential for precise positioning, satellite orbit determination, and understanding changes in Earth’s mass distribution.