Question: how are the stars going out

David Wilson answered on 13 Nov 2014:

stars go out when they run out of hydrogen in their core. Stars are powered by hydrogen fusing (sticking together) into helium, releasing energy. If there’s no hydrogen left it stars fusing helium, then carbon, swelling up into a huge red giant but soon there’s nothing more that it can fuse together to make energy. It will lose its outer layers until only the core if left, a really dense, super hot ball of carbon called a white dwarf. This will then slowly cool down over billions of years. But don’t worry, the Sun has five billion years left before it gets to this stage!