Nuclear fusion in massive stars eventually fails to counteract gravitational pressure, leading to core collapse and a subsequent supernova explosion. This collapse generates a shock wave that ejects the star's outer layers, leaving behind a core fragment, often a neutron star, which can be propelled at high speeds due to asymmetrical explosion dynamics. The Chandrasekhar limit, set at approximately 1.39 solar masses, determines whether a star will become a neutron star or a black hole, with progenitor stars needing to exceed eight solar masses to undergo core collapse. Stars below this limit will instead evolve into white dwarfs after forming a planetary nebula. Understanding these processes is crucial for comprehending stellar evolution and supernova mechanics.