About J1737-3102
J1737-3102 is an uncommon pulsar. It spins once every 768.672 ms, has a dispersion measure of 280 pc cm⁻³ and carries a surface magnetic field around 5.42×10^12 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.