The extremely hot interior of the Earth is slowly cooling down, but exactly how fast remains unknown. By studying how we…

The extremely hot interior of the Earth is slowly cooling down, but exactly how fast remains unknown. By studying how well a common deep-Earth mineral conducts heat, researchers from Carnegie and ETH Zurich have found that the planet’s interior may be cooling much faster than we thought.
Earth is essentially a giant pie that’s been cooling on a windowsill for 4.5 billion years. At first, it was broiling hot from surface to center, covered in oceans of magma, but as it cooled from the outside in, a solid crust of rock formed. The core is still emanating huge amounts of heat into the mantle, which drives vital processes like plate tectonics and volcanism, but it too will eventually cool off.
Exactly how long this will take is a mystery, but the scientists on the new study sought some answers by investigating a key mineral called bridgmanite.