The Long Michelson Interferometer was a

radio telescope A radio telescope is a specialized antenna (radio), antenna and radio receiver used to detect radio waves from astronomical radio sources in the sky. Radio telescopes are the main observing instrument used in radio astronomy, which studies the r ...

interferometer Interferometry is a technique which uses the '' interference'' of superimposed waves to extract information. Interferometry typically uses electromagnetic waves and is an important investigative technique in the fields of astronomy, fiber opt ...

built by

Martin Ryle Sir Martin Ryle (27 September 1918 – 14 October 1984) was an English radio astronomer who developed revolutionary radio telescope systems (see e.g. aperture synthesis) and used them for accurate location and imaging of weak radio sourc ...

and co-workers in the late 1940s beside a rifle range to the west of

Cambridge Cambridge ( ) is a List of cities in the United Kingdom, city and non-metropolitan district in the county of Cambridgeshire, England. It is the county town of Cambridgeshire and is located on the River Cam, north of London. As of the 2021 Unit ...

, England. The interferometer consisted of 2 fixed elements 440m apart to survey the sky using Earth rotation. It produced th
Preliminary survey of the radio stars in the Northern Hemisphere
at 45 MHz - 214 MHz. The telescope was operated by the Radio Astronomy Group of

Cambridge University The University of Cambridge is a Public university, public collegiate university, collegiate research university in Cambridge, England. Founded in 1209, the University of Cambridge is the List of oldest universities in continuous operation, wo ...

and

Antony Hewish Antony Hewish (11 May 1924 – 13 September 2021) was a British radio astronomer who won the Nobel Prize for Physics in 1974 (together with fellow radio-astronomer Martin Ryle) for his role in the discovery of pulsars. He was also awarded the ...

received the

Nobel Prize for Physics The Nobel Prize in Physics () is an annual award given by the Royal Swedish Academy of Sciences for those who have made the most outstanding contributions to mankind in the field of physics. It is one of the five Nobel Prize, Nobel Prizes establi ...

in 1974 for this and later work in radio interferometry.

References

A preliminary survey of the radio stars in the Northern Hemisphere
Ryle, M.; Smith, F. G.; Elsmore, B., (1950),

Monthly Notices of the Royal Astronomical Society ''Monthly Notices of the Royal Astronomical Society'' (MNRAS) is a peer-reviewed scientific journal in astronomy, astrophysics and related fields. It publishes original research in two formats: papers (of any length) and letters (limited to ...

, Vol. 110, p. 508 Cavendish Laboratory Radio telescopes Interferometric telescopes 1940s establishments in England {{observatory-stub