Parts from the Cambridge Interplanetary Scintillation Array

Discovering pulsars

This is part of the four-acre radio telescope used in one of astronomy’s most famous chance discoveries. In 1967, student Jocelyn Bell noticed a ‘bit of scruff’ on the telescope’s data charts. Astronomers realised that the unusual signal, which repeated regularly, came from a new class of cosmic object. Initially, these objects were nicknamed LGM, for ‘little green men’. But rather than aliens, they are rapidly spinning dense stars. They are called pulsars and over 1800 are now known.