About J2143+0654
J2143+0654 is an uncommon pulsar. It spins once every 9,428.229 ms and carries a surface magnetic field around 1.99×10^13 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.