What keeps the earth's core so hot? It's had over 3 billion years to cool.?

Answer 1

This is historically a really interesting question that perplexed scientists for years. Some of the very first estimates of the earth's age were based on newly discovered thermal radiation equations based on the earths size. They all grossly underestimated the true age of the earth because they didn't take into account the one thing that has been keeping the earth hot all these years: the decay of radioactive elements in our planet's core!

Answer 2

There are several reasons why the core of the Earth is so hot.
For one, when the material that made the Earth came together, a great deal of heat was released. After that, the Earth melted and all the heavier elements sank to the center to form the core. As this segregation process took place, additional heat was released when the molten iron and other heavy metals sank to the center. Impacts from space also made the young Earth very hot, especially the impact that created the Moon. Secondly, the core of the Earth is under enourmous pressure. Extreme pressure also creates extreme temperatures. The pressure is so great the iron and nickle there is more than twice as dense as it would be at the surface. Iron would be a gas at the temperatures though to exist in the inner core, but matter under high pressure does not follow the same rules as it does on the surface. The overlying layers of rock are poor conductors of heat, henceforth the only way heat can get out of the core is through slow connvection in the mantle, which is itself mostly solid. The mantle and crust act like a insulating blanket and only allow heat to escape slowly. There is a great deal of uranium, thorium, potassium and other radioactive isotopes in the core also. When these unstable isotopes and elements decay, the subatomic particles and gamma rays strike nearby atoms. This and the break-up of unstable nuclei creates a great deal of heat. Finally, the Earth is a very large rocky planet. A large planet takes a lot longer time to cool than a small one because it's surface area relative to it's interior volume is much smaller. A small planet radiates away internal heat much faster than a big one. That is why the Moon is inert now while the Earth is still active geologically.

Answer 3

radioactive decay keeps it hot. the decay and subsequent release of energy keeps the core at its temperature. since the energy has no place to go the core won't cool down for quite a long time.

Answer 4

That's a common misperception. The core is actually as cold as ice. Volcanic eruptions happen because of large underground coal fires that heat up the area near the surface.

Answer 5

good question. But the core IS cooling, only very slow.
The inner core used to be completely liquid, and yet, it has been solidifying and cooling slowly but certainly (about 100 degrees per billion years).

Answer 6

The tidal forces and its pull that generates the heat. So as long as we have a Moon ,there is your generator.

Answer 7

extreme pressure

Answer 8

uhh....im just here for the drinks