Of battleship turrets and pulsars

The Crab Nebula is the remnant of a supernova which exploded - or rather was seen to explode - in 1054AD. The pulsar at the heart of the nebula - the neutron star left over when the star's core collapsed at the moment of the supernova - was discovered in 1968, very shortly after Jocelyn Bell's discovery of the first pulsar using the Cambridge radio telescope.

The pulsar, and its associated nebula, have been and continue to be of great interest to astronomers. But the pulsar itself has a direct...