Stars that are more than a few times as massive as our sun contain so much mass that, when they run out of fuel and the outward pressure diminishes, they collapse inwards. This causes the material to heat up rapidly again, and blow the star apart. Such occurrences are called novas, or, if very massive stars are involved, supernovas. The photo above is what's left after a supernova explosion that's centuries old. The remaining core can be a white dwarf, neutron star, or black hole, depending on the force of the explosion.
|
