White dwarfs and neutron stars are both "stellar corpses", the remnant of stars. White dwarfs roughly cram the Sun's mass into an Earth-sized sphere, neutron st

White dwarfs and neutron stars are both "stellar corpses", the remnant of stars. White dwarfs roughly cram the Sun's mass into an Earth-sized sphere, neutron stars cram that amount of mass into a sphere of about 10km diameter. Oh, and neutron stars have mountains: height differences on their crust of a few centimeters or less. Scaling that height difference takes more energy than scaling Mount Everest. Gravity is weird. (Armchair interest in astrophysics; this is roughly correct but I'm sure others can point out nuances better).