About J1903+0327
J1903+0327 is an epic pulsar. It spins once every 2.15 ms, has a dispersion measure of 297.52 pc cm⁻³ and carries a surface magnetic field around 203,554,012 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.