The Earth’s core has not stopped rotating

The Earth’s core has stopped spinning and may have reversed direction

Earth’s solid inner core layer may have paused its rotation recently and started to spin in the opposite direction instead

Earth’s inner core may have started to spin in opposite direction

It has been very widely reported that the Earth’s solid inner core may have stopped rotating, or started rotating in reverse. The same claim has also been shared on Facebook.

This is potentially misleading, because it is based on scientific research which did not say that the earth’s inner core had stopped rotating. It actually said that the inner core might have stopped rotating faster than the mantle (the part of the Earth’s interior between the crust and the core).

In other words, there was no suggestion in the paper that the inner core had stopped rotating altogether—only that the difference between the speed of its rotation and the mantle’s may have changed.

Many of the media reports may have been misled by a press release from Nature Geoscience, the journal that published the research. Its first line originally said: “The rotation of the Earth’s solid inner core may have recently paused and could be reversing”. Following contact from Full Fact, the journal updated the release with clearer language.

A spokesperson for Springer Nature told Full Fact: “We have clarified that the term “reversal” (and derivations thereof) are commonly used by the research community that focuses on this area to describe the phenomena in question, namely the slowing or speeding up of the inner core relative to the mantle.

“However, we recognise that for a generalist audience these terms can be misleading without additional context and should not have been used in the press release.”

Following contact from Full Fact, both the Independent and Metro have updated their articles. The BBC has not yet responded. The story was misleadingly reported by many media outlets but we only contacted these three before writing this fact check.

What the research said

The original research paper measured the way that seismic waves—vibrations often caused by earthquakes—travelled from one side of the planet to the other. It found that these waves have behaved differently in the past decade.

The authors said that this “suggests that inner-core rotation has recently paused”—by which they meant “differential rotation of Earth’s inner core relative to the mantle”.

As a different news article from Nature explains, the differential rotation of the Earth’s inner core has been a matter of scientific debate for many years.

However, there is no suggestion that the inner core has stopped rotating altogether. Rather than spinning slightly faster than the rest of the planet, this research suggests it may now be spinning at the same speed, or slower.

Image courtesy of NASA