About J1858+0609g
J1858+0609g is an uncommon pulsar. It spins once every 484.35 ms and has a dispersion measure of 381.5 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.