About J1730-2900
J1730-2900 is an uncommon pulsar. It spins once every 1,538.427 ms, has a dispersion measure of 289 pc cm⁻³ and carries a surface magnetic field around 3.73×10^12 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.