Earth’s core has ‘stopped spinning’ and may be going in reverse, study says
The inner core of the earth is thought by researchers to have ceased spinning and may now be turning in the other direction.
Scientists Yi Yang and Xiaodong Song from Peking University in China claim that the earth’s inner core has nearly stopped rotating in the past decade and that it may even be ‘experiencing a turning-back in a multidecadal oscillation, with another turning point in the early 1970s.’ These findings were presented in a paper that was published in the journal Nature.
The article investigates the unexplained inner workings of the globe by analyzing seismic waves generated by earthquakes that ruptured deep within the planet. Their records of the seismic waves coming from the inner core go all the way back to the beginning of records kept in Alaska, which was in the 1960s.
They have hypothesized that these shifts are a part of a cycle known as “oscillation,” which is expected to endure for seven decades. According to Xiaodong Song, a seismologist at Peking University and one of the authors of the study, the inner core is like “a world within a planet,” and as such, the movement of the inner core is evidently very essential. But the mechanism behind it is, for the most part, a mystery.
Made from mostly solid iron, it packs a punch
According to National Geographic, it has a radius of 758 miles (1,220 km) and a temperature of approximately 9,392 degrees Fahrenheit (5,200 degrees Celsius). From what we have learned so far, it is mostly composed of solid iron. That’s one meatball with a kick to it.
“There are two major forces acting on the inner core,” Yang and Song said in an email. “We think that the core is, relative to the surface of the Earth, rotating in one direction and then the other, like a swing,” He continued. They mentioned that the electromagnetic force is the first one. The fluid motion that originates from the earth’s outer core is what generates the magnetic field that shields the globe from the effects of cosmic radiation.
It is anticipated that the magnetic field that is acting on the metallic inner core will cause the inner core to rotate through a process known as “electromagnetic coupling.” They continued: “The other is gravity force. The mantle and inner core are both highly heterogeneous, so the gravity between their structures tends to drag the inner core to the position of gravitational equilibrium, so-called gravitational coupling.”
Rotating back and forth in a game of “Tug of War”
On the other hand, this “tug of war” leads the inner core to spin back and forth for an approximately “70-year oscillation.” In addition, the researchers noted that their findings provide credence to “the multidecadal pattern of the rotation,” which they referred to as “the inner rotation.”
According to a seismologist at the University of Southern California named John Vidale, who was not part in the research project, there is a great deal of research that is in contradiction with one another regarding the rotation of the inner core. And despite the fact that its inaccessibility makes it challenging to confirm, he continues to have optimism.