About J1930+2441
J1930+2441 is an epic pulsar. It spins once every 5.767 ms, has a dispersion measure of 69.57 pc cm⁻³ and carries a surface magnetic field around 225,999,535 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.