About J2017+2043
J2017+2043 is an uncommon pulsar. It spins once every 537.143 ms, has a dispersion measure of 60.49 pc cm⁻³ and carries a surface magnetic field around 7.40×10^11 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.