Jodrell Bank and the Lovell Telescope (1957): Radio Astronomy

The Lovell Telescope at Jodrell Bank in Cheshire, England, was the largest steerable radio telescope in the world when it was completed in 1957. Built by the University of Manchester under the astronomer Bernard Lovell, it won international fame within weeks by tracking the rocket that carried Sputnik 1 into orbit. More than six decades later it remains in use, and Jodrell Bank Observatory is a UNESCO World Heritage Site.

Origins: from wartime radar to radio astronomy

Bernard Lovell (1913–2012) was a physicist who spent the Second World War developing airborne radar. Returning to the University of Manchester in 1945, he wanted to use surplus army radar equipment to study cosmic rays. Electrical interference from the city’s trams made work in central Manchester impossible.

In December 1945 he moved the equipment to Jodrell Bank, a field station of the university’s botany department about 30 kilometres south of the city. Lovell and his colleagues soon found that their radar picked up echoes from meteor trails, and Jodrell Bank became a leading centre for the new science of radio astronomy, which studies the radio waves given off by objects in space.

In 1947 the team built a fixed “transit” telescope, a 66-metre dish of wire mesh that could observe only the strip of sky passing directly overhead. Its results convinced Lovell that a much larger dish that could be pointed anywhere in the sky would open up new research.

Building the Mark I

Lovell worked with the engineer Charles Husband, whose firm designed the new telescope. Funding came mainly from the government’s Department of Scientific and Industrial Research and the Nuffield Foundation, and construction began in 1952.

The design was bold. The dish, 76.2 metres (250 feet) across, hung between two towers and could tilt and turn to follow objects across the sky. To save money and time, the engineers reused the gun-turret racks and gears of the Royal Navy battleships HMS Royal Sovereign and HMS Revenge for the elevation drive. The whole moving structure weighed around 3,200 tonnes.

Costs rose sharply, partly because of design changes and rising steel prices. The final bill was roughly £700,000, about twice the original estimate, and the university was left with a heavy debt. A parliamentary committee questioned the spending, and Lovell faced the possibility of personal financial ruin.

Tracking Sputnik

The telescope was completed in the summer of 1957. On 4 October that year the Soviet Union launched Sputnik 1, the first artificial satellite. Within days the Mark I was being used as a radar to bounce signals off the satellite’s carrier rocket and track its path. It was the only instrument in the West able to do so.

The publicity transformed the telescope’s reputation. Jodrell Bank also followed later Soviet and American spacecraft, and in 1960 it tracked the American probe Pioneer 5 deep into space for NASA. In 1960 a donation from the motor manufacturer Lord Nuffield cleared the remaining debt.

Science and space tracking

The telescope’s main purpose was astronomy. In the 1950s and 1960s Jodrell Bank astronomers measured the sizes of distant radio sources, helping to show that some were extremely compact, work that contributed to the discovery of quasars, the brilliant cores of distant galaxies. Later the telescope became one of the most important instruments for studying pulsars, the rapidly spinning neutron stars first discovered at Cambridge in 1967.

Jodrell Bank also played a well-known role in 1966, when its scientists received pictures transmitted by the Soviet probe Luna 9 from the surface of the Moon. The images were published in British newspapers before the Soviet Union released its own.

The telescope has been upgraded several times. In the early 1970s it received a new reflecting surface and was known as the Mark IA, and a further new surface was fitted in the early 2000s. In 1987, on its 30th anniversary, it was renamed the Lovell Telescope. Today it is part of e-MERLIN, a network of British radio telescopes that work together to make very detailed images.

By the numbers

Timeline

• 1945, December: Bernard Lovell moves radar equipment to Jodrell Bank.
• 1947: The fixed 66-metre transit telescope is built.
• 1952: Construction of the Mark I telescope begins.
• 1957, summer: The Mark I telescope is completed.
• 1957, October: The telescope tracks the carrier rocket of Sputnik 1 by radar.
• 1966, February: Jodrell Bank receives images from Luna 9 on the Moon.
• 1987: The telescope is renamed the Lovell Telescope.
• 2019, July: Jodrell Bank Observatory is inscribed as a UNESCO World Heritage Site.

Why it matters

The Lovell Telescope showed that a giant, fully steerable radio dish was possible and helped make Britain a leader in radio astronomy. Its tracking of Sputnik linked it forever with the start of the Space Age, and its research on quasars and pulsars has kept it at the forefront of astronomy for more than sixty years.