About J0302+2252
J0302+2252 is an uncommon pulsar. It spins once every 1,207.165 ms, has a dispersion measure of 18.99 pc cm⁻³ and carries a surface magnetic field around 3.19×10^11 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.