A pulsar is a very strange astronomical object that is the result of a collapsing star. The conservation of angular momentum means the small collapsed star spins very rapidly, causing it to "pulse" its radio signals on a very reliable frequency, hence the name "Pulsar".
Peter Walters and Katie Davies of England's University of the West decided to 3D print a pulsar. Well, not actual size, of course. We don't have a 3D printer available of that size yet.
The print represents the strength of the radio signals received from the Vela Pulsar (PSR B0833-45) as it rotates. The bizarre astronomical object emits radio, optical, X-ray and gamma rays. Very nasty stuff if you happen to be nearby. We'd rather just admire the beautiful 3D print of its signals.