NASA has unveiled a new three-dimensional model of the geoid, created from satellite observations of Earth. In the visualization, the planet appears not as a perfect sphere but as an irregular object with bulges and dips, according to infohub.kz.
The geoid represents the hypothetical surface of the global ocean under the influence of gravity alone, ignoring wind, currents, and tides. The model reveals variations in gravitational pull caused by the uneven distribution of mass within the planet. Regions with denser rocks and other massive structures create stronger gravitational attraction, appearing as conditional 'hills' on the model. In areas where density is lower, gravity is weaker, resulting in 'depressions'.
To make these differences visible, NASA scientists exaggerated the height variations by about 10,000 times. In reality, the differences are only a few dozen meters and are invisible to the naked eye. One of the highest points of the geoid is near Iceland, about 85 meters above the average level. The deepest area is south of India, where the surface is approximately 106 meters below the average.
The model took 15 years to create. It is based on data collected over 15 years, including about 1 billion observations from satellites. The geoid is used not only to study Earth's gravitational field. Scientists employ it to track changes in sea level, glacier melting, depletion of groundwater reserves, and the effects of droughts. According to observations, from 2002 to 2025, Antarctica lost an average of about 135 gigatons of ice per year, while Greenland lost about 264 gigatons. The model also helps analyze changes in water reserves and monitor extreme droughts in various regions, including Spain and France.