Deep beneath the Earth's surface, there's a scorching ball of iron surrounded by an ocean of boiling hot liquid metal – the Earth's core. It's as toasty as the surface of the Sun ...

Something’s cooking down inside Earth. At the center of our planet ... Just like a piping hot lasagne cooling on a plate, the surface quickly chills and the center is the last to moderate.

The Earth was already more than 600 million years old when life began. The planet had cooled down from its original ... seas gave rise to life, with hot, mineral-rich volcanic vents acting as ...

Geothermal water from deeper in the Earth can be used directly for heating homes and offices, or for growing plants in greenhouses. Some U.S. cities pipe geothermal hot water under roads and ...