Starship Asterisk*

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In a few minutes the collapsing core is converted from nickel and iron nuclei to mostly alpha particles (helium nuclei). Deprived of support from the core, the overlying mass of the star freefalls. As this mass impacts onto the now largely Helium core it is further compressed and heated. The Helium is then dissociated into the fundamental subatomic particles - protons, neutrons, and electrons; and for a brief time the electrostatic force of the electrons resists the pressure of the star's overlying weight. But this resistance, known as electron degeneracy pressure, is not enough to resist the force of gravity given the tremendous mass of the star. In a white dwarf star electron degeneracy pressure is able overcome by gravity only if the mass is under a limit close to the Chandrasekhar limit. When the core approaches this limit the proton finds itself in a sea of electrons that cause the proton to be unstable against electron capture or "inverse beta decay". Electrons are absorbed into protons transmuting each electron-proton pair into a single neutron and releasing a neutrino in the process. Within fractions of a second the core is converted to a mass of neutrons at near nuclear density -- the core is literally a giant neutron-rich atom!