Is it a bird, is it a plane…? Is it an alien?! No, it's actually a pulsar! Scientists used to jokingly label unidentified signals from space as 'Little Green Men'. Thanks to Jocelyn Bell Burnell and the Interplanetary Scintillation Array, we now know that some of these signals are from pulsars, rapidly spinning neutron stars that emit beams of radiation from each magnetic pole that we detect as regular pulses from Earth. A stylised diagram of these pulses became the cover art for Joy Division's