English radioastronomer. At the Mullard Radio Astronomy Observatory, Cambridge, he developed the technique of sky-mapping using 'aperture synthesis', combining smaller dish aerials to give the characteristics of one large one. His work on the distribution of radio sources in the universe brought confirmation of the Big Bang theory. He won, with his co-worker Antony Hewish, the Nobel Prize for Physics 1974.
Ryle was born in Brighton, Sussex, and studied at Oxford. During World War II he was involved in the development of radar. After the war he joined the Cavendish Laboratory in Cambridge, and in 1959 he became the first Cambridge professor of radioastronomy, responsible for most of the radiotelescope developments. He was Astronomer Royal 1972-82.
Larger and larger radio telescopes were built at the Cambridge sites, resulting in the Cambridge Catalogue Surveys, numbered 1C-5C, giving better and better maps of radio sources in the northern sky. The 3C survey, published 1959, is used as reference by all radioastronomers. The 4C survey catalogued 5,000 sources.
The first 'supersynthesis' telescope, in which a fixed aerial maps a band of the sky using solely the rotation of the Earth, and another aerial maps successive rings out from it concentrically, was built in 1963, and a 5-km/3-mi instrument was completed in 1971. The programmes for which it is in use includes the mapping of extragalactic sources and the study of supernovae and newly born stars. It can provide as sharp a picture as the best ground-based optical telescopes.