About J1929+1615g
J1929+1615g is an uncommon pulsar. It spins once every 44.6 ms and has a dispersion measure of 308.7 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.