In a new study, we've observed clues that distinguish the very deepest part of Earth's core

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Not so long ago, Earth’s interior was thought to be made up of four layers: the crust, mantle, (liquid) outer core and (solid) inner core.

In a new study published today in Nature Communications, we provide further evidence for the existence of an “innermost inner core” – a distinct internal metallic ball embedded in the inner core like the most petite Russian nesting doll.