About J1849+0409
J1849+0409 is an uncommon pulsar. It spins once every 761.194 ms, has a dispersion measure of 63.97 pc cm⁻³ and carries a surface magnetic field around 4.10×10^12 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.