{{Short description|Radio telescope in Cambridge, England}} {{Use dmy dates|date=October 2025}} {{refimprove|date=November 2025}} {{Infobox telescope}} The '''4C Array''' is a cylindrical paraboloid radio telescope at the Mullard Radio Astronomy Observatory, near Cambridge, England. It is similar in design to the Molonglo Observatory Synthesis Telescope. It is 450 m long, 20 m wide, with a second, moveable element (now mostly removed; some of it is still visible, beyond COAST).{{Citation needed|date=January 2024}} The first large aperture synthesis telescope (1958), it was also the first new instrument to be built at Lord's Bridge, after the Observatory was moved there in 1957, and needed {{convert|64|km|mi|abbr=on}} of reflector wire (since removed).{{Citation needed|date=January 2024}} The 4C operated at 178 MHz (1.7 m), and located nearly 5000 sources of the 4C (4th Cambridge) catalogue published in 1965 and 1966, which helped establish the evolution of the radio galaxy population of the universe.<ref>{{Cite web |last=Longair |first=Malcolm |title=A Brief History of Radio Astronomy in Cambridge |url=https://www.astro.phy.cam.ac.uk/about/history?}}</ref> The telescope is now inoperable.<ref>{{Cite web |date=2019-09-11 |title=Report - - The 4C Array radio telescope – Mullard Observatory – Cambridge – August 2019 {{!}} Other Sites |url=https://www.28dayslater.co.uk/threads/the-4c-array-radio-telescope-mullard-observatory-cambridge-august-2019.120012/ |access-date=2025-11-13 |website=28DaysLater Urban Exploring Forums |language=en-GB}}</ref>
It is flanked to the northwest by the Cosmic Anisotropy Telescope enclosure and to the south by the One-Mile and Half-Mile Telescopes.{{Citation needed|date=January 2024}}
thumb|250px|none|One antenna of the One-Mile Telescope (left), two of the Half-Mile Telescope (centre) and the remains of the 4C Array (right) in June 2014
== References == <references />
{{Authority control}} {{Use British English|date=October 2025}}
Category:Cavendish Laboratory Category:Radio telescopes Category:Interferometric telescopes Category:Astronomical observatories in England
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