NASA reports that seasonal redistribution of water across oceans, ice sheets, and land pushes Earth's center of mass slightly off its geometric center — shifting back and forth by mere fractions of an inch throughout the year.
A NASA-led research team is tracking these small oscillations because the center of mass serves as a fundamental reference point. Satellite navigation systems and precise elevation measurements both depend on knowing exactly where it sits.
Water moving between polar ice, groundwater, and oceans as seasons change is the main driver behind this subtle wobble, according to the source.
