Scientists Find Earth’s Core Slowing Enough to Reverse Spin Direction

There is a solid metal orb at Earth’s core that spins on its own, unrelated to the Earth’s rotation. The rate and direction of rotation of the inner core have been disputed by scientists.

Recent studies have shown that the inner core’s speed has varied, and scientists are unsure of the precise consequences of decelerating or even reversing it.

In 1936, Danish seismologist Inge Lehmann found the ball-shaped inner core, which lies about 3,220 miles below the surface of the Earth. Iron and nickel make up the bulk of it. According to estimates, the inner core may become as hot as the sun’s surface, which is nearly 10,000 degrees Fahrenheit.

The iron atoms inside the Earth’s inner core are so dense and subjected to such high pressure that the plasma there acts as a solid.

The inner core is pulled to spin by the Earth’s magnetic field. On a 70-year cycle, the rotation of the inner core is thought to go faster and then slower. The inner core may have spun quicker than Earth itself during the past, according to a theory from 2023, but its current rotation seems to be slower.

A slowdown of the inner core compared to the mantle was first detected by researchers in 2008, and by 2023, the spin had somewhat reversed direction. Within the next five to ten years, according to the researchers, the rotation will begin to accelerate again.

According to a new study, the Earth’s magnetic field may have been affected by the recent slowing of its deep core. To shield Earth from dangerous solar radiation, the Earth’s magnetic field is powered by electrical currents generated by the circulation of metal-rich material in the planet’s outer core. The magnetic field may be affected if the inner core slows down or reverses.

Dr. Lauren Waszek, a senior professor of physical sciences at James Cook University in Australia, says researchers need more data and better multidisciplinary methods to study the impacts of the inner core slowdown. Waszek observed that he couldn’t imagine it having any impact on an individual’s lifetime.