Scientists accidentally discover Earth's inner core is less solid than expected

Earth's inner core is made primarily of iron.

For a long time, scientists thought the Earth's inner core was a solid ball of metal, sort of like a planet within a planet that sits some 3,000 miles (4,828 kilometers) below the surface.

However, researchers from the University of Southern Carolina (USC) now say they discovered — almost by accident — that the Earth's inner core may be much more malleable.