Why is the sun so hot?

Our sun is a big fiery ball of gas. It is very bright and very hot. So hot that we can’t even send spacecraft there without them burning up! But how does the sun make all that heat? We asked physics grad student Raj Katti help us find the answer.Got a question that’s a real scorcher? ? Send it to us at BrainsOn.org/contact, and we’ll get bRIGHT to work finding the answer.