About J1838-01
J1838-01 is an uncommon pulsar. It spins once every 183.295 ms and has a dispersion measure of 320.4 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.