Behind the expedition to the Earth's mantle 04:06. Earth's inner core, a hot iron ball the size of Pluto, has stopped spinning in the same direction as the rest of the planet and might even be ...

A study suggests the Earth’s inner core, which rotates independently from Earth’s surface, slowed down — but it didn’t stop or reverse direction.

Seismologists noted in the 1880s that S waves generated by earthquakes didn’t pass all the way through Earth, and so they concluded that Earth’s core was molten.

A study suggests the Earth’s inner core, which rotates independently from Earth’s surface, slowed down — but it didn’t stop or reverse direction.

A study suggests the Earth’s inner core, which rotates independently from Earth’s surface, slowed down — but it didn’t stop or reverse direction.

A study suggests the Earth’s inner core, which rotates independently from Earth’s surface, slowed down — but it didn’t stop or reverse direction.

A study suggests the Earth’s inner core, which rotates independently from Earth’s surface, slowed down — but it didn’t stop or reverse direction.

A study suggests the Earth’s inner core, which rotates independently from Earth’s surface, slowed down — but it didn’t stop or reverse direction.

A study suggests the Earth’s inner core, which rotates independently from Earth’s surface, slowed down — but it didn’t stop or reverse direction.

A study suggests the Earth’s inner core, which rotates independently from Earth’s surface, slowed down — but it didn’t stop or reverse direction.

A study suggests the Earth’s inner core, which rotates independently from Earth’s surface, slowed down — but it didn’t stop or reverse direction. A recent study suggests the speed at which the Earth’s ...