Earth has Another Core Inside It’s Core

By Avi Qin '25

While I doze off in the middle of science class, immersed in my own thoughts, I frequently wonder: What are humans yet to discover? Generally, we like to think that scientists have gotten pretty far in figuring how most things work. However,the mysteries of planet Earth pose the most daunting and perplexing challenge for modern geologists. 

Recently, there have been new academic findings on the Earth’s inner core. What we (high school students) typically know of the inner core is that it is located at the center of Earth and has an incredibly high heat and pressure. However, research published by Dr. (add first name or initial here)Tkalcic and Thanh-Son Pham in the journal Nature Communications in February 2023 indicates that there is an innermost inner core with distinctive rotation. In their paper, both researchers investigate data collected from seismometers close to the epicenter of major earthquakes, where they measured seismic waves that bounced back and passed through the innermost inner core multiple times. “We processed 200 events and found that 16 of them had these bouncing waves,” Dr. Tkalcic said in the New York Times.  

More shockingly, preceding research published in Nature Geoscience by Peking University chair professor Xiaodong Song and associate research assistant, Yi Yang showed that since 2009, seismic records showed little difference. This suggests that the innermost inner core rotation has paused. 

All of these novel discoveries about the center of Earth are useful for us in understanding planetary formation and the history of our universe. According to Vernon Cormier, a professor of physics at the University of Connecticut who was not involved with the research, the inner core is a range of 600 million to a billion years old. 

Nonetheless, the new research alerts us to the importance of teaching ourselves about our own planet, as the activity and age of Earth’s inner core are intertwined with humankind to some extent. How cool is that?

Sources:

Phạm, TS., Tkalčić, H. Up-to-fivefold reverberating waves through the Earth’s center and distinctly anisotropic innermost inner core. Nat Commun 14, 754 (2023). https://doi.org/10.1038/s41467-023-36074-2

Other links I need to properly cite: https://www.nytimes.com/2023/02/23/science/earth-core-seismic-waves.html

https://www.cnn.com/2023/01/25/world/earth-core-turning-scli-scn-intl/index.html