While Earth’s inner core apparently started spinning faster during the 1970s, its rotation eventually slowed and synchronized with Earth’s around 2009.
Our planet’s super-hot spinning iron core may now be spinning slower than our planet’s surface, according to a new study.
The authors of the new research, Yi Yang and Xiaodong Song of Peking University in China, postulated that “the rotation of the inner core recently stopped”, even though the inner core had previously started rotating faster than the rest of the Earth in the 1970s.
“We think the inner core rotates, relative to the Earth’s surface, back and forth, like a seesaw,” the researchers said, as quoted by media. “A seesaw cycle lasts about seven decades.”
The study authors came to these conclusions after studying seismic waves from repeated earthquakes that have occurred over the past six decades. These waves pass through the planet’s core and can help track its movements.
The researchers further suggested that the rotation of the inner core came into sync with the rotation of our planet around 2009, and that the next change in this rotation cycle is believed to occur during the 2040s.