About J1207-5050
J1207-5050 is a rare pulsar. It spins once every 4.843 ms, has a dispersion measure of 50.64 pc cm⁻³ and carries a surface magnetic field around 173,421,644 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.