About J0518+5125
J0518+5125 is an uncommon pulsar. It spins once every 912.512 ms, has a dispersion measure of 39.24 pc cm⁻³ and carries a surface magnetic field around 4.22×10^11 G.
The collapsed core of a star that exploded: about one and a half Suns of matter crushed into a ball the size of a city, held up only by the refusal of neutrons to be squeezed further.