About J1900-0051
J1900-0051 is an uncommon pulsar. It spins once every 385.194 ms, has a dispersion measure of 136.8 pc cm⁻³ and carries a surface magnetic field around 2.37×10^11 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.