By Andrea Hargraves 
essence a landA hot ball the size of Pluto, it would have reversed the direction of its rotation, according to a study published on Monday (23).
This “planet within a planet”, about 5,000 kilometers from the surface and made up mainly of iron, has stopped spinning and will, for the time being, be moving in the opposite direction, indicating study Published by Nature Geoscience.
The exact mechanism of rotation of this sphere, which is motionless because it floats in the outer core fluid, remains difficult to understand. What little is known is based on analyzes of seismic waves caused by earthquakes as they pass through a center planet.
By analyzing seismic wave data over the past six decades, Xiaodong Song and Yi Yang peking university, He concluded that the core’s rotation “nearly stopped around 2009 and then rotated in the opposite direction”.
“We think that, relative to the Earth’s surface, the central core rotates in one direction and then the other, like a swing,” they told AFP.
“The full cycle of this movement lasts about seven decades, which means that it changes direction approximately every 35 years,” the researchers added.
The last change in circulation, before 2009, occurred in the early 1970s, and the next change will occur in the mid-40s, completing the cycle, according to Chinese scientists.
They add that this motion roughly adjusts to changes in the length of the day, and subtle changes in the exact time it takes for Earth to rotate on its own axis.
So far, there are few indications of the effect of this rotation on Earth’s surface. However, the authors guarantee that they are convinced that there are physical connections between all the layers that make up the Earth.