Earth’s interior is cooling faster than expected

The evolution of our Earth is the story of its cooling: 4.5 billion years ago, extreme temperatures prevailed on the surface of the young Earth, and it was covered by a deep ocean of magma. Over millions of years, the planet’s surface cooled to form a brittle crust. However, the enormous thermal energy emanating from the Earth’s interior set dynamic processes in motion, such as mantle convection, plate tectonics and volcanism. The Earth's core gives off heat to the mantle (orange...