Home · Science · Sep 21 archive
NASA Reveals Earth's Center of Mass Drifts Less Than Thought
Confirmed
In Short: NASA's Space Geodesy Project has revealed that Earth's center of mass moves significantly each year due to seasonal changes, water redistribution, and snow accumulation.
NASA's Space Geodesy Project has revealed that Earth's center of mass moves significantly each year due to seasonal changes, water redistribution, and snow accumulation, according to a study published Wednesday, September 16, 2026. The project, launched in 2018, uses twin satellites to map monthly fluctuations in Earth's gravitational pull due primarily to the mass movement of water above and below ground.
The study found that snow accumulation in North America and Eurasia reaches a maximum in March, shifting Earth's center of mass about 3 millimeters toward the North Pole. This shift is part of a larger pattern where Earth's center of mass continually swivels around its geometric center by as much as several millimeters due to seasonal changes and water redistribution.
To measure Earth's center of mass accurately, scientists must look to space. Satellites don't just orbit Earth; they orbit the exact center of Earth's mass. Any small shift in that center of mass means there is a shift in orbital trajectories, which is crucial for satellite navigation and elevation measurements.
The team also observed longer-term shifts in the center of mass due to geological effects such as volcanic activity and earthquakes. These shifts, while less frequent, contribute to the overall dynamic nature of Earth's mass distribution.
Knowing Earth's center of mass down to the order of millimeters reveals some interesting facts about our planet. For instance, 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.
According to NASA, the size of the movement of Earth’s mass center back and forth each year is now estimated to be about half of what was believed eight years ago. This refined understanding is a result of improved satellite technology and more precise measurements.
The study highlights the dynamic nature of Earth’s mass distribution, which changes with the seasons. This information is crucial for various applications, including satellite navigation and elevation measurements, where even small shifts can have significant impacts.
While much about these deep processes remains unknown, there are certain seismic waves whose trajectories can indicate irregularities near the literal center of the Earth as they are scattered and deflected.
What this adds
The study isn't the first attempt to pin down Earth’s center of mass, but it is the most precise to date, reducing our uncertainty to less than a millimeter.
Background
NASA scientists have refined their understanding of Earth's center of mass, revealing that it shifts less than previously thought.
NASA's Space Geodesy Project has revealed that Earth's center of mass moves significantly each year due to seasonal changes, water redistribution, and snow accumulation.
What's confirmed
- “We’re now estimating the size of the movement of Earth’s mass center back and forth each year to be about half of what we believed it to be eight years ago,” said Argus.
- They found that snow accumulation in North America and Eurasia reaches a maximum in March and shifts Earth’s center of mass about 3 millimeters toward the North Pole.
What's still developing
- These allowed us to determine the center of mass to within a centimeter or so.
- The result reduces our uncertainty to less than a millimeter.
- A conventional space elevator would begin near Earth's equator and extend far beyond geostationary orbit, where an orbiting object remains over the same location on Earth.
- (CREDIT: Wikimedia / CC BY-SA 4.0) Getting into space still requires throwing away an extraordinary amount of mass.
- Its current materials guidance says single-crystal graphene remains the ultimate target because of its combination of tensile strength and low mass.
- Charnia did not have a mouth, organs, or any visible means of movement, and was essentially a ‘goo-filled bag’ – like a sedentary jellyfish – however, it is thought to be one of the earliest animals to exist.
- And sometimes Earth's features are really, really subtle – so much so that they might be impossible to see with the naked eye.
- They can stretch for kilometers but are generally only 100 to 500 meters (328–1640 feet) wide and less than 9 meters deep.
- “A Palestinian life is no less valuable than any other life on this earth.” Hours later, Kraft revealed that Sheeran had already contacted him before Macklemore issued that challenge, asking Kraft to commit $2 million to match what Kraft described as Sheeran’s own donation for humanitarian aid in the region.
- This artist’s concept shows a very young star encircled by a disk of gas and dust, the raw materials from which rocky planets such as Earth are thought to form.
- Look after it a bit while I worked, while my husband worked (both freelance, therefore maternity/paternity leave-less, sick pay-less, holiday pay-less), because there was no way on God’s good earth we could afford London childcare fees?
- Scientists and sci-fi authors have envisioned massive cities and settlements on the lunar surface.