Science Questions

Why is the sun so hot? Megan in Hartford

The sun is so hot because the sun is a giant nuclear reactor in the sky. It's mixing on hydrogen with another hydrogen to make another light gas called helium. You can find helium in the funky balloons that float. When you mix the two hydrogens together, you get a lot of heat energy, and so the sun on its surface is at least six thousand degrees centigrade. That's what keeps us warm.

October 2005