Why Doesn't the Sun Burn out?

The sun does not run out of oxygen for the simple fact that it does not use oxygen to burn. The burning of the sun is not chemical combustion. It is nuclear fusion. ... At the same time, hydrogen atoms in the fuel bond with oxygen atoms to make water molecules.

Why does the sun not burn itself out?

The Sun does not "burn", like we think of logs in a fire or paper burning. The Sun glows because it is a very big ball of gas, and a process called nuclear fusion is taking place in its core. ... Hydrogen really doesn't burn, it fuses, into helium. So no oxygen is required!

Is it possible for the sun to burn out?

But in about 5 billion years, the sun will run out of hydrogen. ... That's when the sun will become a red giant. For about a billion years, the sun will burn as a red giant. Then, the hydrogen in that outer core will deplete, leaving an abundance of helium.