Breakthrough Discovery: Scientists Uncover Surprising Softness of Earth’s Inner Core

Scientists have long believed that the Earth’s inner core is a solid metal ball, about 3,000 miles beneath our feet. However, recent research from the University of Southern California (USC) suggests that this core might actually be more flexible than we thought.

John Vidale, a professor at USC, led the study and explained that the researchers didn’t initially aim to learn about the inner core’s physical characteristics. Instead, they were focused on observing how the inner core’s rotation is slowing down, a change that previous studies had already noted. They analyzed seismic data from earthquakes to track this movement.

The team looked at 121 repeating earthquakes that occurred between 1991 and 2024. These earthquakes took place near the South Sandwich Islands, just north of Antarctica.

While examining the seismic waveforms, they stumbled upon surprising data that challenged their previous beliefs about the inner core. Some waveforms displayed unusual traits that caught Vidale’s attention. “As I was analyzing decades of seismic data, one dataset really stood out,” he said. “Later, I realized I was looking at evidence that the inner core is not solid.”

By refining their analysis technique, the team discovered that these seismic waveforms indicated some movement within the inner core. This suggests that instead of being completely unmoving and solid, the inner core might actually be changing and shifting.

Vidale noted that their findings showed evidence of structural changes near the surface of the inner core. These changes could be connected to the core’s slowing movement and may help scientists understand more about the Earth’s thermal and magnetic fields. Interestingly, they suggested that this structural alteration might even have minute effects on how long a day lasts.

The research was published in the journal Nature Geoscience, revealing a fascinating new perspective on our planet’s core.