About J1955+2908
J1955+2908 is an epic pulsar. It spins once every 6.133 ms, has a dispersion measure of 104.49 pc cm⁻³ and carries a surface magnetic field around 432,176,363 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.