The Long Michelson Interferometer was a radio telescope interferometer built by Martin Ryle and co-workers in the late 1940s beside a rifle range to the west of Cambridge, England.
The interferometer consisted of 2 fixed elements 440m apart to survey the sky using Earth rotation.
The telescope was operated by the Radio Astronomy Group of Cambridge University.
Martin Ryle and Antony Hewish received the Nobel Prize for Physics in 1974 for this and later work in radio interferometry.
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