About J1955+6708
J1955+6708 is a rare pulsar. It spins once every 8.565 ms, has a dispersion measure of 57.15 pc cm⁻³ and carries a surface magnetic field around 332,396,985 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.