A new study suggests that Earth’s inner core may have deformed over the past two decades, altering its once spherical shape. Researchers found that some areas of the inner core’s edges may have shifted by over 100 meters, challenging long-held assumptions about its structure.
Led by Professor John Vidale of the University of Southern California, the study—published in Nature Geoscience—adds to growing evidence that the inner core’s rotation has slowed in recent years. The findings could have significant implications for understanding Earth’s magnetic field, which is generated by the core and protects the planet from harmful solar radiation.
Scientists used seismic waves from repeated earthquakes between 1991 and 2023 to track changes in the inner core’s movement. Their analysis suggests that the deformation is occurring where the solid inner core meets the surrounding molten outer core, an area of extreme heat and dynamic flow.
Earth’s core is crucial to maintaining the planet’s magnetic field. Without it, Earth could face a fate similar to Mars, which lost its magnetic field billions of years ago, leaving it exposed to harsh solar winds.
While the study sheds light on the inner workings of our planet, experts caution that further research is needed to confirm the findings. Some scientists speculate that changes in the core could be linked to fluctuations in Earth’s magnetic field, but the full implications remain uncertain.
Professor Vidale emphasized that while these changes are unlikely to impact daily life, they are key to understanding Earth’s deep interior. “In all likelihood, this finding doesn’t affect our daily lives one iota, but we really want to understand what’s happening in the middle of the Earth,” he said.
