Neutron star

Neutron stars occurred when nuclear fusion in a supergiant star stops. The core collapses upon itself, a process known a gravitational collapse. The gravity within the stars was so massive that the electrons and protons in the atoms were destroyed, leaving only neutrons. The energy released in the destruction of the atoms caused a supernova. Sometimes, large white dwarfs could collapse to form neutron stars. Also, collapse could result in electron and proton stars.