S21·E4 Celebrates its 20th anniversary

In April 1957 The Sky at Night began. It could not have started at a better time; within months the Space Age opened, with the launch of Sputnik 1, and over the next few years astronomy saw some of the most spectacular advances of all time. Today, 20 years later, men have visited the moon; rockets have flown past the planets and even landed on some of them; new giant telescopes have probed further into the universe than Man has ever done before, and each year brings its new quota of discoveries. Every month, since April 1957, The Sky at Night has presented the changing scene. In this 20th anniversary programme Patrick Moore discusses the past and the future with some of Britain's leading figures in astronomy.