Earth's molten iron core beneath the Pacific reversed direction in 2010, satellite data reveals
A patch of Earth's molten iron core beneath the Pacific reversed direction in 2010, shifting from westward to eastward flow, per ESA satellite data spanning 1997-2025. The core drives Earth's magnetic field. Flow has weakened since 2020. Source: ESA, via ScienceDaily.
A region of Earth's molten iron outer core beneath the equatorial Pacific abruptly reversed direction in 2010, shifting from a westward drift to a strong eastward flow, according to a new reconstruction using satellite and ground magnetic data collected between 1997 and 2025. The analysis drew on the European Space Agency's Swarm and CryoSat missions along with Germany's CHAMP satellite. The outer core sits roughly 2,200 kilometers beneath the surface and generates Earth's magnetic field as it moves; scientists had long assumed the core flows mainly westward, making this reversal a challenge to that assumption. Researchers found the eastward flow has weakened since 2020, suggesting the pattern is still evolving, though they do not yet know whether it is a short-lived fluctuation, part of a repeating oscillation, or a new stable state for core circulation. The finding shows how much of current scientific understanding of the core's motion rests on a satellite record that only stretches back to the late 1990s, and how fast an assumption that stood for decades can be overturned once continuous data becomes available. Source: European Space Agency, via ScienceDaily.