About J1740-5340B
J1740-5340B is an epic pulsar. It spins once every 5.787 ms and has a dispersion measure of 72.2 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.