For decades, scientists believed the Earth’s inner core was a solid ball of metal, but new research has revealed it may be more malleable. Researchers at the University of Southern Carolina found that the inner core’s speed of rotation is decreasing, and their analysis of seismic waveform data from 121 earthquakes between 1991 and 2024 showed unexpected properties.
Principal investigator John Vidale discovered a dataset of waveforms that stood out from the rest while analyzing multiple decades’ worth of seismograms. The team improved their resolution technique and found evidence that the inner core is not as solid as previously thought, but rather undergoes structural changes.
The discovery may shed light on the Earth’s thermal and magnetic fields, as well as its slowing rotation. The researchers believe the change in the inner core could have “minutely altered the length of a day.” This new understanding could help scientists better comprehend our planet’s inner workings.
Source: https://www.space.com/the-universe/earth/scientists-accidentally-discover-earths-inner-core-is-less-solid-than-expected