Scientists have discovered some unusual activity going on at the center of the Earth. Recent research published in Nature revealed that the inner core of our planet has been rotating at a slower pace compared to the mantle and surface since approximately 2010. This finding supports a controversial discovery made in 2023, suggesting that the inner core may have reversed its rotation in relation to the rest of the Earth every 35 years or so.
Geophysicist John Vidale from the University of Southern California noted that the latest data indicates that the inner core is moving back slower than it had moved forward, adding a layer of complexity to the situation. In simple terms, while the inner core is still rotating in the same general direction as the surface and mantle, from a different perspective, it appears to be turning in the opposite direction compared to a couple of decades ago.
The study involved analyzing earthquake data from the South Sandwich Islands near Antarctica between 1991 and 2023. By studying the seismic waves from repeating earthquakes, researchers were able to determine that the inner core had indeed altered its rotation sometime around 2008. The slower rotation speed could be attributed to gravitational forces from the surrounding mantle, which makes up the majority of Earth’s mass. This could be causing the inner core to deform and distort its oscillation pattern.
Vidale’s team found a total of 25 matching waveforms out of 200 comparisons, indicating a shift in the inner core’s rotation. This aligns with the 2023 study’s conclusion that the inner core’s gyration likely follows a 70-year cycle. However, some researchers like Lianxing Wen from Stony Brook University argue that the inner core’s surface movements could explain the data without the need for a rotational shift.
Geophysicist Hrvoje Tkalčić believes that the truth lies somewhere between these differing viewpoints. More data and observations are necessary to fully understand the inner core’s behavior accurately. By monitoring the inner core’s rotation over the next few years, scientists hope to gain further insights into its complex movements.
The Earth’s inner core continues to be a source of intrigue and mystery for researchers around the world. The ongoing studies and observations aim to shed light on the inner workings of our planet and how its core influences geological processes on the surface. With further research and collaboration among scientists, we may soon unlock more of the secrets hidden deep within the Earth.
