NASA Watches Earth’s Weight, Finds Center of Mass
Seasonal changes redistribute enough water around Earth to shift the planet’s center of mass back and forth by fractions of an inch relative to its geometric center. NASA scientists are on the case, tracking the oscillations because Earth’s center of mass is a crucial reference point for satellite navigation and elevation measurements. A team, led […]
NASA scientists are refining a technique to measure Earth's center of mass, which moves due to seasonal changes in water distribution across the planet. This motion, as small as fractions of an inch, is crucial for satellite navigation and elevation measurements. A team led by NASA's Jet Propulsion Laboratory in California has developed a new method using ultraprecise satellite tracking to estimate the displacement to within fractions of an inch.
The method combines GPS tracking with orbital data from multiple satellites to account for the shifting mass of water and ice. The study, published in Geophysical Journal International, found that snow accumulation in North America and Eurasia causes Earth's center of mass to shift about 3 millimeters toward the North Pole in March.
Conversely, rainwater in the Amazon River basin shifts it 2.2 millimeters toward South America in April. Monsoon water in Southeast Asia adds to the oscillation in November. The researchers noted that understanding these seasonal shifts helps improve global positioning systems and navigation, benefiting everything from shipping to agriculture.
Written by urgent.news from NASA's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
