Martin Ryle - 'Eminent Briton'
The Royal Mail has issued a stamp featuring Sir Martin Ryle as part of a series called 'Eminent Britons' on the occasion of the 50th anniversary of the publication of the Cambridge Catalogue.
Sir Martin Ryle (1918 - 1984) was the British radio astronomer who developed revolutionary radio telescope systems and used them for accurate location of weak radio sources. With improved equipment, he observed the most distant known galaxies of the universe. Ryle, who was awarded the Gold Medal of the RAS in 1964, and Antony Hewish shared the Nobel Prize for Physics in 1974, the first Nobel prize awarded in recognition of astronomical research.
After earning a degree in physics at Oxford in 1939, he worked with the Telecommunications Research Establishment on the design of radar equipment during World War II. After the war he moved to the Cavendish Laboratory in Cambridge, where he became an early investigator of extraterrestrial radio sources and developed advanced radio telescopes. In 1957 he became director of the Mullard Radio Astronomy Observatory,was knighted in 1966 and between 1972-82 was Astronomer Royal.
Ryle's early work centred on studies of radio waves from the Sun, sunspots, and a few nearby stars. He guided the Cambridge radio astronomy group in the production of radio source catalogues. The Third Cambridge Catalogue (1959) helped lead to the discovery of the first quasi-stellar object (quasar). To map such distant radio sources as quasars, Ryle developed a technique called aperture synthesis. By using two radio telescopes and changing the distance between them, he obtained data that, upon computer analysis, provided tremendously increased resolving power. In the mid-1960s Ryle put into operation two telescopes on rails that at the maximum distance of 1.6 km (1 mile) provided results comparable to a single telescope 1.6 km in diameter. This telescope system was used to locate the first pulsar, which had been discovered in 1967 by Hewish and Jocelyn Bell Burnell of the Cambridge group.