In 2011, something strange happened inside the Earth. We've been investigating it for years and still don't know what it was

Scientists identified an unusual reversal in liquid iron-nickel flow in part of Earth’s outer core, first noticed in 2011.

A retrospective analysis of data from 1997 to 2025 found the flow shifted from weakly westward to strongly eastward between 2010 and 2012.

That eastward pattern persisted until 2020, then began to weaken, with the anomaly appearing localized beneath the Pacific Ocean.

Researchers say it may be a temporary fluctuation, periodic oscillation, or system adjustment, but the cause is still unconfirmed.

Understanding these core changes matters because they help shape Earth’s magnetic field, which shields the planet and satellites from solar storms.