Building record 7756/10 - Jodrell Bank Observatory: Cosmic Noise Hut

<1> Historic England, 2011, The National Heritage List for England, 1442129 (Web Site). SCH6528.

The buildings around The Green were the hub of both research and teaching onsite. The construction of these new buildings marked a serious commitment by the University to the development of a permanent radio observatory at the Jodrell Bank site, and they are the earliest surviving purpose-built structures for that use. The Link Hut (originally called the Noise Hut or Cosmic Noise Hut) was built in 1949 as a control and receiving room for the adjacent 30ft telescope (a paraboloid mesh radio-telescope that was sited to the west of the hut). This telescope was designed to investigate ‘cosmic noise’, i.e. the background extra-terrestrial radio signals that had been first discovered by Karl Jansky in 1932. This was the first paraboloid telescope at Jodrell Bank purpose-built for radio astronomy, and marked a development from using the modified fixed ‘Transit’ telescope which was originally built to study cosmic rays and meteors. The first work based in the Noise hut related to the scintillation of radio sources, analogous to the twinkling of stars observed in visible light, and by working with others, Jodrell Bank showed that the ionosphere produced this effect. In late 1953, the 30ft telescope was modified to observe emission at low frequency from inter-stellar hydrogen, without success. However, higher frequency hydrogen emissions were successfully observed, and assisted in work on measuring the distances to radio stars, which proved important when the Lovell Telescope (Grade I, List entry 1221685) became operational.

Externally the appearance of the original building is little altered except for the painted finish and plastic rainwater goods. However, also in late 1953, the Noise Hut was extended with a darkroom to house a spectrohelioscope given to the observatory. It was attached to the east of the original hut, but originally it extended slightly further to the north; it has since been reduced in depth so that its rear wall is now aligned with that of the original hut. Concrete pads in the floor relate to the change of use of this room in 1955, for the experiments that led to the discovery of the Hanbury Brown and Twiss effect. The window in the front wall of the extension is also an insertion, as is the internal cross-partition which also overlies one of the concrete floor-pads. The left-hand front doorway of the original hut has also been blocked. In the 1970s the Development Lab was attached to the east wall of the extension. The original roofing material has been replaced with similar material.

Robert Hanbury Brown (1916-2002) was one of the original ‘boffins’, working from 1936 to 1942 under Sir Robert Watson-Watt on the development of radar. Arriving at Jodrell Bank in 1949, in 1950 he was one of the astronomers responsible for confirming sources of radio emissions beyond our own galaxy. In 1955, together with Richard Q Twiss, he conducted in the Noise Hut the first experiments in optical intensity interferometry. This relies on the effect of interference between simultaneous signals from the same source, on simultaneous measurements of the intensity of that source. When applied to the interaction of sub-atomic particles the Hanbury Brown and Twiss effect also explains observed results and has been important in advancing our understanding of quantum physics.

<2> Chris Blandford Associates, 2016, Jodrell Bank Observatory, Conservation Management Plan (Client Report). SCH8560.