Why is the sun hot?, now before you jump on the comments and say “because it’s the sun, stupid” think about it, our sun is basically a giant nuclear reactor at the centre of our solar system but not like the ones on earth. They create energy by nuclear fission, that is they split large atoms like uranium in to smaller lighter ones and in the process it releases large amount of energy. Atomic bombs also work in the same way which is why they are so destructive. The sun creates its energy b