About J1643-1224
J1643-1224 is an epic pulsar. It spins once every 4.622 ms, has a dispersion measure of 62.4 pc cm⁻³ and carries a surface magnetic field around 295,596,803 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.