Patrick Moore celebrates the 50th birthday of the radio telescope at Jodrell Bank in Cheshire, created just in time to pick up the radar signal from the satellite Sputnik. It has been at the centre of radio astronomy ever since and has been responsible for the discovery of quasars, gravitational lenses and groundbreaking research into pulsars and cosmic explosions such as supernovae. Astronomer Bernard Lovell talks about how it came to be built, despite huge engineering and financial challenges.