A new study has revealed that Earth’s inner core might’ve stopped spinning and could be moving in reverse.
According to scientists at the University of China, Yi Yang and Xiaodong Song, Earth’s inner core has nearly stopped rotating in the last ten years. In addition, they theorize Earth may even be “experiencing a turning-back in a multidecadal oscillation, with another turning point in the early 1970s.”
Their research paper, published in Nature Geoscience, examines the mysterious insides of our planet. They studied tectonic waves from earthquakes that penetrated its core.
Their data on the inner core’s waves date back to the 1960s. Now, scientists theorize these new movements are part of an ‘oscillation’ cycle. In addition, they also believe this cycle could last at least 70 years.
According to Xiaodong Song, a seismologist at Peking University and co-author of the research, Earth’s inner core is “a planet within a planet.” Yet, despite their findings, scientists are still perplexed by how it works.
Currently, scientists know the inner center consists primarily of solid iron. They also know it has a radius of over 750 miles and a temperature of around 9,392° F, per reports from National Geographic.
New research reveals ‘two major forces’ contributing to Earth’s inner core
“There are two major forces acting on the inner core,” Yang and Song wrote in an email.
According to the two, the first is the electromagnetic force. Our planet’s magnetic field, which protects Earth from cosmic radiation, is created by fluid motion from the exterior core.
Scientists believe the magnetic field on the metallic inner core will force the inner core to rotate. This process is called “electromagnetic coupling.”
They added: “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.”
Despite the push and pull behavior, it causes the inner core to spin back and forth. In addition, this behavior could last for nearly 70 years.
The scientists also said their research backs up the inner rotation and “the multidecadal pattern of the rotation.”
According to John Vidale, a University of Southern California seismologist who was not a part of the study, there are many clashing studies regarding the inner core rotation. Although it’s challenging to confirm or deny, he stays optimistic.
“It’s certainly possible we’ll never figure it out,” he said in an interview with The New York Times. “I’m an optimist. The pieces are going to fall into place someday.”