About J2023+2853g
J2023+2853g is an uncommon pulsar. It spins once every 11.33 ms and has a dispersion measure of 22.8 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.