About J1717-5800
J1717-5800 is an uncommon pulsar. It spins once every 321.793 ms, has a dispersion measure of 125.22 pc cm⁻³ and carries a surface magnetic field around 2.54×10^11 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.