[SauronOfMordor]

This sounds very risky. If the center cools then what.

You're kidding, right? The amount of heat energy down there is huge, and constantly being renewed from the radioactive elements in the core

[cripplecreek]

Yep we got us one massive nuclear reactor down there the size of a small planet.

[glorgau]

The amount of heat energy down there is huge, and constantly being renewed from the radioactive elements in the core

So, essentially, this is evil nuclear power? ;-)

[FRForever]

> constantly being renewed from the radioactive elements in the core

Sorry, Sauron. No more radioactivity down there than there is up here. That’s the Sun you’re thinking about. The Earth’s core is cooling — but over spans of billions of years, since the only ways the Earth as a whole can lose heat are radiation and gas escape.

The main reason it’s still warm is that you’re right about it being a huge amount of heat to start with. The volume of the solid earth is ~20x that of the entire ecosphere (even when very generously defined as being out to the edge of space) and several thousands of times denser — and that large, dense volume is very hot, around 10,000 degrees.

So there’s a *whole bunch* of heat energy down there. So yeah, I think it can stand a couple of glasses of ice water. In fact, you could pour all the oceans of the world on it to convert them to superheated steam to cook everybody on the planet and still not make much of a dent.