A groundbreaking study has revealed that Earth’s inner core is not a solid sphere as previously believed, but is undergoing dynamic structural changes. The new findings challenge long-held views of Earth’s deepest layer and may drastically alter our understanding of the planet’s evolution, its magnetic field, and its rotation.
Scientists have long assumed that the inner core, more than 3,000 miles beneath the Earth’s surface, was a solid iron and nickel ball. But decades of seismic data have made a surprising discovery: the inner core surface is altering shape, indicating that it is far more dynamic than scientists had assumed.
This research, by researchers interpreting seismic waveforms of earthquakes that happened between 1991 and 2024 close to the South Sandwich Islands in Antarctica, revealed anomalous data indicating physical alterations in the structure of the inner core. The scientists concentrated on the manner in which the inner core spins and slows down movement, specifically observing its change in rotation rates, including a speed-up in 2010.
Seismic waves, created by earthquakes, held the secret to this finding. The waves move through Earth’s layers, and by observing how they act as they move through the inner core, scientists can deduce their physical characteristics. The anomalous seismic waveform data revealed that the inner core is being reshaped continuously, a process not previously included in geological models.
The new results suggest that the inner core is not a static, unchanged structure but rather undergoes ongoing and intricate changes. This “shape-shifting” behavior may provide new insights into the forces operating far beneath the Earth, and pose questions regarding the long-term stability of this critical layer.
Learning how the inner core behaves is key to enhancing our understanding of the planet’s magnetic field, which is produced by the spinning molten metals of the outer core. This new dynamic model can potentially unlock deeper insights into the Earth’s internal workings, such as its rotation and the driving forces behind plate tectonics.
As researchers begin to scrutinize the data, this find has the potential to redefine textbooks and compel scientists to rethink old concepts regarding the shape of our planet.
