A neutron star is a stellar remnant left after a giant star with too little mass to form a black hole dies. It is dense enough to reach the neutron degeneracy pressure, when the pressure is high enough to combine protons and electrons to form neutrons, and therefore has a mass of greater than 1.4 solar masses (the Chandrasekhar limit).

The maximum mass of a neutron star is given by the Tolman–Oppenheimer–Volkoff limit, and is somewhere between 2.0 and 3.0 solar masses.

Stellar Classes
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