About J1137+7528
J1137+7528 is an epic pulsar. It spins once every 2.513 ms, has a dispersion measure of 29.17 pc cm⁻³ and carries a surface magnetic field around 91,303,584 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.