Question: Why does the sun have to be hot instead of cold

Eoin Carley answered on 19 Nov 2014:

Hello!
This is a nice question, and the simple answer is…because it’s really really big! All the material the sun has makes its gravity really strong. Gravity is trying to crush the sun as much as it can. All this crushing makes he center of the sun so dense and with so much pressure it turns into a giant nuclear reactor. All those nuclear reactions make the sun very very hot!