Planetary disc around a pulsar. Artwork of a disc of rocky debris (brown) surrounding a pulsar (centre). A pulsar, a rotating neutron star, is the collapsed, super-dense core of a massive star that has blown off its outer layers in a supernova. The force of the supernova pulverised the planets surrounding the star and formed glowing clouds of gas and dust (pink). The stellar and planetary debris eventually formed the disc seen here, which could form into new planets. This artwork, published in 2006, was inspired by infrared observations with the Spitzer Space Telescope of a disc around pulsar 4U 0142+61, 13,000 light years away in the constellation Cassiopeia.