Their findings, suggesting that this inner inner core might indicate a second, extreme cooling event sometime in our world's past, are detailed in a new study recently published at the online scientific site, Journal of Geophysical Research: Solid Earth.
Dr. Joanne Stephenson, lead author and PhD researcher in the Research School of Earth Sciences at the Australian National University explained that investigating the structure of the inner core can aid in understanding more about the Earth’s history and evolution.
“Traditionally we’ve been taught the Earth has four main layers: the crust, the mantle, the outer core and the inner core," she said in a University press release. "The idea of another distinct layer was proposed a couple of decades ago, but the data has been very unclear.”