The Earth is formed of the crust, the mantle and the inner and outer cores.
The rotation of Earth’s inner core may have paused and it could even go into reverse, new research suggests.
Earth’s core is about the size of Mars and about 1/3rd of Earth's mass. It consists mostly of iron and nickel.
A new study has now revealed that the Earth's inner core recently stopped spinning and then changed its spin orientation in the opposite direction.
The rotation came to a grinding halt in 2009 and then it surprisingly turned in an opposite direction.
One cycle of the swing is about seven decades, meaning it changes direction roughly every 35 years, the researchers said.
It previously changed direction in the early 1970s, and predicted the next about-face would be in the mid-2040s.
The team of researchers analysed earthquakes mostly from between 1995 and 2021
Researchers have said that the rotation of the core is related to the changes in the length of the day
It could lead to small variations in the exact time it takes for Earth to rotate on its axis and that there are links between the different layers of the planet -crust, mantle, and core.
Earth's inner core was first discovered in 1936 as researchers were studying seismic waves.