About J1748-2446aj
J1748-2446aj is a rare pulsar. It spins once every 2.959 ms, has a dispersion measure of 238.63 pc cm⁻³ and carries a surface magnetic field around 654,157,307 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.