About J1803-3329
J1803-3329 is an uncommon pulsar. It spins once every 633.412 ms, has a dispersion measure of 170.9 pc cm⁻³ and carries a surface magnetic field around 4.68×10^11 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.