Stock image showing the inner layers of the Earth. A new paper states that the inner core may contain an extra, innermost core. iStock / Getty Images Plus. Before this discovery, the ...

Scientists say they’ve confirmed Earth’s inner core has been slowing down. Here’s what it could mean — and why the topic has been the subject of fierce debate.

Earth’s core consists of a solid iron-nickel ball rotating within a layer of liquid metal. But that ball may not be as simple as it seems: new research suggests the inner core contains its own ...

The rotation of Earth’s inner core may have paused and it could even go into reverse, new research suggests.

Earth's inner core is a roughly moon-size chunk of solid iron and nickel that lies more than 3,000 miles (4,800 kilometers) below our feet. It is surrounded by the outer core — a superhot layer ...

They found that the inner core was rotating in the same easterly direction as the Earth itself, albeit slightly faster than the other solid layers—the mantle and surface.

As the Earth gradually cools, the inner core expands outwards at the surrounding iron-rich liquid "freezes." That said, it is still extremely hot, at least 5,000 Kelvin (K) (4,726.85°C) .

Earth Day is on Tuesday, April 22, this year. The annual observation is set aside to increase awareness around environmental issues like climate change, pollution, endangered species and other ...