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NASA’s 3D Geoide Map Shows Exaggerated Bumps That Reflect Gravity, Not Surface Shape

The visualization is a gravity-based reference used to measure altitude, calibrate satellite navigation, and track sea-level and ice-mass changes.

Overview

  • NASA published a 3D visualization of the Earth’s geoide that has circulated widely and drawn attention for its large-looking bulges and dips.
  • The image depicts the geoide, an equipotential surface that represents how oceans would sit under gravity and rotation alone, not the planet’s visible topography.
  • The visualization amplifies real geoide variations by a factor of 10,000 so tiny gravity-driven differences become visible to the eye.
  • The underlying GOCO06s gravity model was built from more than one billion satellite observations collected over about 15 years by 19 satellites, including NASA’s GRACE and ESA’s GOCE.
  • Local geoide deviations cited by NASA reach roughly +85 meters in places such as Iceland and −106 meters in parts of southern India, and the model is used for precise altitude, mapping, navigation calibration, and monitoring sea-level and glacier-mass changes.