About J0837-4135
J0837-4135 is an uncommon pulsar. It spins once every 751.625 ms, has a dispersion measure of 147.2 pc cm⁻³ and carries a surface magnetic field around 1.65×10^12 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.