* Supernovae are the explosive death of stars. They happen when a star runs out of fuel and can no longer support its own gravity. The core collapses, leading to a massive explosion.
* There's nothing left after a supernova. The explosion blasts away most of the star's material, leaving behind either a neutron star or a black hole.
* No star can survive a supernova. The intense energy release is catastrophic, completely destroying the star.
However, there are some exceptions:
* Multiple stars in a system can each experience a supernova. If a star system has multiple stars, they can each individually undergo supernovae.
* Type Ia supernovae are special cases. These supernovae occur in binary systems when a white dwarf star accretes material from a companion star until it reaches a critical mass. While this involves two stars, the explosion itself happens in the white dwarf, which is the remnant of a star that has already died.
So, while a single star can't have multiple supernovae, multiple stars in a system can each experience one, and some types of supernovae involve the remnants of stars that have already died.
