Earth runs on massive amounts of heat, enough to melt iron in the core and create our magnetic field, enough to power the constant movement of plate tectonics. Where all this heat comes from is a mystery...but we're getting closer.
The inner core of our planet is roughly as big as the Moon, and we can only guess what's going on deep inside our planet. We might now have an answer...and it's even more volatile and weird than we thought.
Earth's continents are constantly changing, moving and rearranging themselves over millions of years - affecting Earth's climate and biology. Every few hundred million years, the continents combine to create massive, world-spanning supercontinents. Here's the past and future of Earth's supercontinets.
Nearly a mile underground, there's an entire ecosystem carving out a rather alien existence in the deepest layer of Earth's crust. These bacteria are totally unlike their brethren nearer the surface, and there might be even stranger bacteria further down.