What is earth powered by?

Answer 1

There are three primary sources of energy for the Earth or any planetary body. Many secondary sources can be derived from these, but everything traces back to the initial three. These are:


1) Solar radiation - Earth receives more energy every day from the heat and light of the Sun than all of humanity expends. However, most of this energy also escapes the Earth (thankfully or we'd all roast) or is absorbed by the ground and water. The Sun produces most of its energy through nuclear fusion.

2) Geothermal pressure - Earth also contains a lot of energy from the formation of our planet. Similar to when you rub your hands together to warm them up, the interior of the Earth warmed up as larger and larger pieces joined up. The layers of surrounding rocks act as isolaters (like laying under a pile of blankets), so that for every 40m you go down the temperature increase by 1°C (or 1°F for 70 feet). In the core, the maximum temperature depends of the melting point of impure iron, roughly 5430°C (9,800°F).

3) Radioactive decay - most elements have stable and unstable isotopes. Unstable isotopes decay and emit energy and sometimes mass to become stable isotopes. Everything around us is at least mildly radioactive. Earth's major heat-producting isotopes ar potassium-40, uranium-235, uranium-238, and thorium-232.