About J1659-4439
J1659-4439 is an uncommon pulsar. It spins once every 353.293 ms, has a dispersion measure of 535 pc cm⁻³ and carries a surface magnetic field around 9.51×10^10 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.