Posts Tagged ‘Brian May’

Jodrell Bank and Amateur Radio Telescopes

December 18, 2015

BBC 4 a few weeks ago broadcast a documentary on the history of Jodrell Bank, Britain’s pioneering radio telescope. Bernard Lovell, its founder and director, had been one of the scientists working on the development of radar during the War, and the radio telescope was originally built using parts left over from the project that were due to be scrapped. In the early days it was very much an ad hoc operation. The size of the telescope’s dish has the radius it has because that was the distance between the van holding its key components in the early days to the edge of the field. The programme covered the history of the telescope from its very beginnings to today. It described how the telescope came into its own in the late 1950s and 1960s when it was the only instrument that could independently verify the first Soviet space missions and their conquest of space. This also caused additional pressure on Lovell, as there was official demand for him to monitor space missions in the USSR, which detracted from his real interest in exploring the heavens through the radio signals sent out into space from stars, nebulae and galaxies.

The Russians also liked and admired Lovell, so much so that on scientific trip to the Soviet Union, the Russians showed him some of their highly top secret space installations, and hinted that he would be very welcome if he left Britain and joined them. Obviously the great man did not take up the offer. Eventually such pressure proved so great that he was off work suffering from depression, and even considered leaving science altogether. Lovell was a Methodist, and to the surprise of his children, at this point in his career he considered joining the clergy. He didn’t, but went back to charting the heavens.

Other highlights of the telescope’s fifty-odd year history was the discovery, by Jocelyn Bell-Purnell, of pulsars. These are neutron stars, small, highly compact stars at the end of their lives, which broadcast a signal into space. The stars are small, about 40 miles or so in diameter, and spin quickly, so it appears that the signal is being sent in pulses. They’re also regular, so that in the first few days when they were discovered one of the theories about them was that they were a signal deliberately sent out into space from an extraterrestrial civilisation. After more pulsars were discovered in the following days, the scientists were able to give the true explanation of their origins.

Since its heyday, much larger telescopes and arrays have been built. Jodrell Bank nevertheless still remains important, contributing valuable research in this area of astronomy.

Indeed. I remember a few years ago an edition of one of the Beeb’s astronomy programmes in which Dara O’Brien and Brian May were up there. O’Brien is a failed mathematician, having dropped out of a university maths course, while May is a properly accredited astrophysicist. He had, it’s true, a twenty-odd year gap in his career, due to performing with Queen, but he finally handed his thesis in a few years ago. It was duly marked, and he passed. This obviously makes him one of the most rock ‘n’ roll scientists ever. I think in the programme they were supposed to be looking for signals from alien civilisations. They didn’t find any, which probably surprised no one, given that scientists have been looking, off and on, for radio signals from aliens since the days of Project OZMA in the late ’60s and 70s. Despite NASA’s optimistic prediction in 1995 that in five years they would be discovered, no has as yet.

Patrick Moore, one of the greatest science communicators and popularisers, always maintained that astronomy was still one of the very few areas of science where amateurs using modest equipment could make a real contribution. I doubt that there are very many ordinary people outside the big observatories, who have an active interest in radio telescopy. Nevertheless, it is possible to build your own radio telescopes. There’s a piece by Trevor Hill, who was a science teacher at Taunton School in Somerset, about how he built a an array of radio telescopes in the book, Small Astronomical Observatories, edited by Patrick Moore (London: Springer 1986). He did so as part of an attempt to get the pupils interested in astronomy. Naturally, he started off by building a normal, optical observatory for a telescope. He turned to radio astronomy at the suggestion of one of the pupils after the normal astronomy session had been cancelled due to rain. The pupil pointed out that radio waves travel through clouds, and so observation wouldn’t be stopped by bad weather. His article in the book describes the radio telescopes he built. This includes a set of Ham radio aerials set up in an array to receive radio waves from solar flares.

Taunton School Radio Telescope

Trevor Hill’s Solar Flare Radio Telescope at Taunton School

He also provides a schematic of the telescope’s construction. As you can see from the photo, even as a small-scale amateur project it’s still very large. Nevertheless, he states that it was very cheap. With the exception of the computer, it cost about £200 in 1995. Which means it’s almost possible for every man or woman to become their own radio astronomer. Obviously, this was before the boom ended, and Cameron got in to hit everyone with massive debt and advancing poverty.

Here’s Tim O’Brien, professor of astrophysics at Manchester University and the radio telescope’s associate director, talking about the telescope on the 70s anniversary of its establishment. It’s great to hear him say that it remains at the cutting edge of research, and may be so for the next fifty years.

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