What is the final stage of a massive star’s life cycle?

When a massive star uses up all its fuel, it can end its life in one of two main ways. If it’s large enough, it explodes in a supernova, and the remaining core collapses into a neutron star or even a black hole. A neutron star is made almost entirely of neutrons and is incredibly dense, while a black hole has gravity so strong that nothing, not even light, can escape. Smaller stars like our Sun don’t explode—they slowly become white dwarfs after shedding their outer layers.