First Cambridge Catalogue of Radio Sources
Encyclopedia
The First Cambridge Catalogue of Radio Sources (1C) refers to the catalogue listed in the article Ryle M, Smith F G & Elsmore B (1950) MNRAS
vol 110 pp508-523 "A Preliminary Survey of Radio Stars in the Northern Hemisphere". http://ukads.nottingham.ac.uk/cgi-bin/nph-bib_query?bibcode=1950MNRAS.110..508R&db_key=AST
The 1C catalogue listed about 50 radio sources, detected at 3.7 m with a fixed meridian interferometer. According to researchers at the Special Astrophysical Observatory http://cats.sao.ru/doc/3C.html, most of the sources from 1C were later recognized to be the effect of confusion, i.e. they were not real objects.
The survey was produced using the Long Michelson Interferometer
at the Old Rifle Range in Cambridge
in 1950. This device operated primarily at a wavelength of 3.7 metres, and was operated using Ryle's
phase switching technique. F. Graham Smith also used the interferometer to measure the electron density in the ionosphere.
The catalogue from this survey is only informally known as the 1C catalogue.
Monthly Notices of the Royal Astronomical Society
Monthly Notices of the Royal Astronomical Society is one of the world's leading scientific journals in astronomy and astrophysics. It has been in continuous existence since 1827 and publishes peer-reviewed letters and papers reporting original research in relevant fields...
vol 110 pp508-523 "A Preliminary Survey of Radio Stars in the Northern Hemisphere". http://ukads.nottingham.ac.uk/cgi-bin/nph-bib_query?bibcode=1950MNRAS.110..508R&db_key=AST
The 1C catalogue listed about 50 radio sources, detected at 3.7 m with a fixed meridian interferometer. According to researchers at the Special Astrophysical Observatory http://cats.sao.ru/doc/3C.html, most of the sources from 1C were later recognized to be the effect of confusion, i.e. they were not real objects.
The survey was produced using the Long Michelson Interferometer
Long Michelson Interferometer
The Long Michelson Interferometer was a radio telescope interferometer built by Martin Ryle and co-workers in the late 1940s beside the rifle range to the west of Cambridge, England. The interferometer consisted of 2 fixed elements 440m apart to survey the sky using Earth rotation. It produced the ...
at the Old Rifle Range in Cambridge
Cambridge
The city of Cambridge is a university town and the administrative centre of the county of Cambridgeshire, England. It lies in East Anglia about north of London. Cambridge is at the heart of the high-technology centre known as Silicon Fen – a play on Silicon Valley and the fens surrounding the...
in 1950. This device operated primarily at a wavelength of 3.7 metres, and was operated using Ryle's
Martin Ryle
Sir Martin Ryle was an English radio astronomer who developed revolutionary radio telescope systems and used them for accurate location and imaging of weak radio sources...
phase switching technique. F. Graham Smith also used the interferometer to measure the electron density in the ionosphere.
The catalogue from this survey is only informally known as the 1C catalogue.