Earth's core is actually hotter than the surface of the sun, reaching temperatures of roughly six thousand degrees Celsius due to radioactive decay and residual heat from planetary formation.

A closer look

Earth's core is actually hotter than the surface of the sun, reaching temperatures of roughly six thousand degrees Celsius due to radioactive decay and residual heat from planetary formation. We are standing on a relatively thin, fragile crust of rock that floats above a swirling, apocalyptic hellscape of molten iron and nickel. We spend trillions of dollars looking up at the sky, terrified of solar flares and asteroids, while completely ignoring the fact that we live directly on top of a gargantuan nuclear furnace. If that crust were to crack open, the sheer thermal energy would vaporize everything we hold dear in seconds. It really puts your daily stresses into perspective when you remember that just a few miles below your feet is an incomprehensibly hot ball of liquid metal waiting to consume us all if the planetary thermostat ever decides to malfunction