About J1903+0534g
J1903+0534g is an uncommon pulsar. It spins once every 357.65 ms and has a dispersion measure of 407.7 pc cm⁻³.
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.