Most massive stars are the shortest lived. A star's life expectancy depends on its mass. The most massive stars quickly use up their fuel supply and explode into an core collapse supernova. Which are some of the most energetic explosions in the universe. Average stars with up to 1.44 solar masses, such as the Sun, face only a slightly less exotic fate. As they run out of hydrogen to fuse in their cores, they swell into red giant stars before shedding their outer layers. The size of a star tells how long a star will live. …show more content…
It is the mass that determines the amount of fuel the star will have to keep burning, which will determine the life expectancy of the star. Stars shine and are stable owing to the thermonuclear reactions in their cores. At the core 4 hydrogen atoms undergo fusion reaction to form 1 atom of helium, releasing a lot of energy. The greater the initial mass to start with, the faster will the nuclear reaction proceed. So a massive star may have a life expectancy of the order of millions of years, while a less massive star may have life expectancy of a few billion years. And here is why they take a million years to