It has been thought that the Earth has four main layers: the crust, the mantle, the outer core, and the inner core. Almost a decade ago, a couple proposed the idea of the presence of another distinct layer. Although, the idea was very unclear.
There’s a mysterious layer at the center of our planet that is difficult to observe. Its distinct properties may point to an unknown, dramatic event in the Earth’s history.
Investigating the inner core structure can help us understand more about the Earth’s history and evolution.
Now, scientists from The Australian National University (ANU) have confirmed the existence of the Earth’s “innermost inner core.” They found evidence that may indicate a change in the structure of iron. It implies that there might be two separate cooling events in Earth’s history.
Lead author of the study, Ph.D. researcher Joanne Stephenson said, “The details of this big event are still a bit of a mystery, but we’ve added another piece of the puzzle when it comes to our knowledge of the Earths’ inner core.”
“We got around this by using a very clever search algorithm to trawl through thousands of the models of the inner core. It’s fascinating – and might mean we have to re-write the textbooks!”
- J. Stephenson et al. Evidence for the Innermost Inner Core: Robust Parameter Search for Radially Varying Anisotropy Using the Neighborhood Algorithm. DOI: 10.1029/2020JB020545