Hello Haley it is believed that in 4 to 5 billion years, the sun will expand as it fuses the last of its core hydrogen. The outer layers of gas will swallow some inner planets (possibly even the Earth). This is commonly referred to as the red giant phase. Then the inner parts of the Sun will stop fusing, contract, and become a white dwarf. So explode may not be quite the right word. Here are some useful websites that talk about the lifetime of stars http://casswww.ucsd.edu/public/tutorial/HR.html http://www.astronomynotes.com/evolutn/s2.htm