About J1903+0925
J1903+0925 is an uncommon pulsar. It spins once every 357.155 ms, has a dispersion measure of 162 pc cm⁻³ and carries a surface magnetic field around 3.67×10^12 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.