Mullard Radio Astronomy Observatory

File:Mrao 1 mile.jpg

One antenna of the One-Mile Telescope at the observatory

File:MRAO Plaque.JPG

The foundation plaque

Mullard Radio Astronomy Observatory (MRAO) is home to a number of large aperture synthesis radio telescopes, including the One-Mile Telescope, 5-km Ryle Telescope, and the Arcminute Microkelvin Imager. Radio interferometry started in the mid-1940s on the outskirts of Cambridge, but with funding from the Science Research Council and a donation of £100,000 from Mullard Limited, construction of the Mullard Radio Astronomy Observatory commenced at Lord's Bridge, a few kilometres to the west of Cambridge. The observatory was founded under Martin Ryle of the Radio-Astronomy Group of the Cavendish Laboratory, University of Cambridge and was opened by Sir Edward Victor Appleton on 25 July 1957. This group is now known as the Cavendish Astrophysics Group.

The site is located at Lord's Bridge, Cambridgeshire on a former ordnance storage facility, next to the now-abandoned Cambridge-Bedford railway line. A portion of the track bed of the old line, running nearly East-West for several miles, was used to form the main part of the "5km" radio-telescope and the Cambridge Low Frequency Synthesis Telescope.

Telescopes

Telescope	Year built	Status
Arcminute Microkelvin Imager Large Array	2007	Active
Arcminute Microkelvin Imager Small Array	2004	Active
Very Small Array (moved to Tenerife in 1999)	1998	Active
Cosmic Anisotropy Telescope made first high-resolution maps of Cosmic Microwave Background fluctuations	1995	Decommissioned
Cambridge Optical Aperture Synthesis Telescope (COAST) first aperture synthesis at optical wavelengths	1993	Operated on clear nights
One receiver from the e-MERLIN array	1990	Active
Cambridge Low Frequency Synthesis Telescope (CLFST)	1980	Decommissioned
Ryle Telescope (formerly 5-Kilometre Telescope)	1971	Decommissioned (repurposed for AMI LA in 2006)
Half-Mile Telescope	1968	Decommissioned
Interplanetary Scintillation Array discovered first pulsar	1967	Decommissioned
One-Mile Telescope	1964	Decommissioned
4C Array, first telescope at the Cambridge's new observatory, used to make the 4C catalogue	1958	Decommissioned

Gallery

The following photographs were taken in June 2014:

• Cmglee Cambridge MRAO station house.jpg

  Lecture hall and exhibition centre in the station house of Lord's Bridge Railway Station

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  Several antennas of the Arcminute Microkelvin Imager Large Array

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  The Arcminute Microkelvin Imager Small Array

• Cmglee Cambridge MRAO CAT.jpg

  Stitched panorama of the Cosmic Anisotropy Telescope enclosure

• Cmglee Cambridge MRAO COAST.jpg

  Part of the Cambridge Optical Aperture Synthesis Telescope

• Cmglee Cambridge MRAO COAST bunker.jpg

  The interior of the bunker of the Cambridge Optical Aperture Synthesis Telescope

• Cmglee Cambridge MRAO MERLIN.jpg

  The receiver from the e-MERLIN array

• Cmglee Cambridge MRAO CLFST.jpg

  Surviving Yagi antennas of the Cambridge Low Frequency Synthesis Telescope

• Cmglee Cambridge MRAO Half Mile Telescope.jpg

  Two antennas of the Half-Mile Telescope

• Cmglee Cambridge MRAO IPS Array.jpg

  Remains of the Interplanetary Scintillation Array

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  One antenna of the One-Mile Telescope (left), two of the Half-Mile Telescope (centre) and the remains of the 4C Array (right)

• Cmglee Cambridge MRAO 4C Array.jpg

  Detail of the remains of the 4C Array, with antennas of the One-Mile Telescope in the background

References

Sources

• The Mullard Radio Astronomy Observatory webpage
• Image from Google maps showing the One-Mile, Half Mile, 4C Array, MERLIN, COAST, CAT and Ryle telescopes.
• Subterranea Britannica entry for Lord's Bridge Forward Filling Depot (also Air Ammunition Park)
• Subterranea Britannica entry for Lord's Bridge Station