About J1911+0101B
J1911+0101B is a rare pulsar. It spins once every 5.384 ms and has a dispersion measure of 196.69 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.