About J1824-2452D
J1824-2452D is a rare pulsar. It spins once every 79.832 ms and has a dispersion measure of 119.5 pc cm⁻³.
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.