About J2016+1948
J2016+1948 is a rare pulsar. It spins once every 64.94 ms, has a dispersion measure of 33.81 pc cm⁻³ and carries a surface magnetic field around 5.16×10^9 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.