Scientists find hidden layer in Earth’s inner core

The video discusses Earth's structure, traditionally known to have four layers: crust, mantle, outer core, and inner core. A new study from the Australian National University suggests an additional layer within the inner core, primarily composed of iron and about two-thirds the size of the moon. This finding implies a significant event in Earth's early history, possibly 4.5 billion years ago.

How does the size of the innermost core compare to the moon?

What does the study suggest about the Earth's history?