About J1949+3106
J1949+3106 is a rare pulsar. It spins once every 13.138 ms, has a dispersion measure of 164.13 pc cm⁻³ and carries a surface magnetic field around 1.12×10^9 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.