Astronomy:List of largest optical refracting telescopes

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The Grande Coupole for the double refractor of Meudon, with roughly 83 cm (33 in) and 62 cm (24 in) aperture lenses on the same mounting, and making its debut in 1891.

Refracting telescopes use a lens to focus light. The Swedish 1-m Solar Telescope, with a lens diameter of 43 inches, is technically the largest, with 39 inches clear for the aperture.The second largest refracting telescope in the world is the Yerkes Observatory 40 inch (102 cm) refractor, used for astronomical and scientific observation for over a century. The next largest refractor telescopes are the James Lick telescope, and the Meudon Great Refractor.[1]

Most are classical great refractors, which used achromatic doublets on an equatorial mount. However, other large refractors include a 21st-century solar telescope which is not directly comparable because it uses a single element non-achromatic lens, and the short-lived Great Paris Exhibition Telescope of 1900. It used a 78-inch (200 cm) Focault siderostat for aiming light into the Image-forming optical system part of the telescope, which had a 125 cm diameter lens. Using a siderostat incurs a reflective loss. Larger meniscus lenses have been used in later catadioptric telescopes which mix refractors and reflectors in the image-forming part of the telescope. As with reflecting telescopes, there was an ongoing struggle to balance cost with size, quality, and usefulness.

This list includes some additional examples, such as the Great Paris telescope, which also used a mirror, and some solar telescopes which may have more complicated optical configurations. The SST has an optical aperture of 98 cm (39.37"), although the lens itself is 110 cm (43.31"). It is a single element lens whereas most of this list are doublets, with a crown and flint lens elements.

Name/Observatory Location at
debut
Modern location name or fate Lens diameter Focal length Built Comments Image
Great Paris Exhibition Telescope of 1900[2] Paris 1900 Exposition Dismantled 1900 125 cm (49.21") 57 m (187 ft) 1900 Fixed lens, scrapped. Aimed via a 2 m reflecting siderostat Great Ex Telescope Telescope.jpg
Swedish 1-m Solar Telescope,
ORM
La Palma,
Spain
- 110 cm (43") total diameter

98cm (39") clear aperture

15 m 2002 Single element non-achromatic objective[3] combined with reflective Adaptive optics and a Schupmann corrector. The lens is 110 cm in diameter stopped down to 98 cm (39"). Swedish Solar Telescope.jpg
Yerkes Observatory[4] Williams Bay, Wisconsin, United States - 102 cm (40") 19.4 m (62 ft) 1897 Largest in current operation.[5] Yerkes 40 inch Refractor Telescope-2006.jpg
James Lick telescope
Lick Observatory
Mount Hamilton, California, United States - 91 cm (36") 17.6 m 1888[2]   Lick Observatory Refractor.jpg
Grande Lunette
Paris Observatory
Meudon, France - 83 cm + 62 cm (32.67"+24.41") 16.2 m 1891 Double telescope Grande Lunette de l'Observatoire de Meudon.jpg
Großer Refraktor
Astrophysical Observatory Potsdam
Potsdam, Deutsches Kaiserreich Potsdam, Germany 80 cm + 50 cm (31.5"+19.5") 12.0 m 1899 Double telescope by Repsold and Sons, optics by Steinheil Potsdam Great Refractor.jpg
Grande Lunette
Nice Observatory
Nice, France since 1988 Côte d'Azur Observatory 77 cm (30.3")[2][6] 17.9 m 1886 Bischoffscheim funded Grande Lunette Nice.jpg
William Thaw Telescope
Allegheny Observatory, University of Pittsburgh
Pittsburgh, Pennsylvania, United States - 76 cm (30") 14.1 m 1914 Brashear made, photographic[7] Allegheny Observatory 2007a.jpg
Pulkovo observatory Saint Petersburg, Russian Empire Destroyed 76 cm (30") 12.8 m (42 feet) 1885 Destroyed during WWII, only lens (made by Alvan Clark & Sons) survives. Pulkovo 30 inch refracting telescope.jpg
28-inch Grubb Refractor
Royal Greenwich Observatory
Greenwich, London, Great Britain - 71 cm (28") 8.5 m 1894 Great Equatorial Telescope full length.JPG
Rolfscher Refraktor[8] Rathenow, Germany - 70 cm (27.6") 20.8 m 1949 Single element non-achromatic objective with Schupmann corrector. Das Rathenower Brachymedial im Optikpark.jpg
Großer Refraktor
Vienna Observatory
Vienna, Austrian Empire Vienna, Austria 69 cm (27" ) 10.5 m 1880 Largest refractor in 1880, by Grubb[9] Refraktor Wien Kerschbaum 1.jpg
Great Treptow Refractor
Treptow Observatory
Berlin, Germany - 68 cm (26.77") 21 m 1896 renamed Archenhold Observatory 1946 ArchenholdObservatory-GreatRefractor.jpg
Innes Telescope Observatory Johannesburg, South Africa Observatory Johannesburg, South Africa 67 cm (26.5") 11.6 m 1909-1925 Still in operation for educational purposes. By Grubb
Yale-Columbia Refractor
Yale Southern Station
Johannesburg, Union of South Africa Relocated 1952 66 cm (26") 10.8 m 1925–1952 Yale-Columbia Refractor moved to Mount Stromlo Observatory in 1952, same telescope as following entry.
Yale-Columbia Refractor
Mount Stromlo Observatory
Mount Stromlo, Australia Destroyed 2003 66 cm (26") 10.8 m 1952 Yale-Columbia Refractor – previously located in South Africa . Relocated to Australia in 1952. Destroyed by bush fire on January 18, 2003.[10] Fisheye image of yale columbia refractor at stromlo.jpg
Leander McCormick Observatory Charlottesville, Virginia, United States - 66 cm (26") 9.9 m 1884 completed c. 1874, installed 1884 Mccormick observatory 1890.jpg
U.S. Naval Observatory Foggy Bottom Washington, DC, United States moved to Northwest, Washington, D.C., 1893 66 cm (26") 9.9 m 1873 Largest refractor in 1873. Alvan Clark & Sons mounting replaced with Warner & Swasey mounting in 1893. US Navy 030826-N-9593R-043 Personnel at the U.S. Naval Observatory in Washington, D.C., prepare the facility's historic 26-inch refractor telescope for optical viewing of Mars.jpg
Thompson 26-inch Refractor[11] Royal Observatory, Greenwich, Great Britain[11][12] Equatorial Group, Herstmonceux, Sussex[11] 66 cm (26")[11] 6.82 m[11] 1896 Manufactured by Sir Howard Grubb as a gift from Sir Henry Thompson; originally used at Greenwich on the same mount as a 30 inch reflector[12] "The Thompson 26-inch telescope" - Royal Observatory Greenwich ca 1900 (7890150450).jpg
Llano del Hato National Astronomical Observatory Llano del Hato, Venezuela - 65 cm (25.6") 10.6 m 1955 Smaller Telescope of Observatorio Nacional de Llano del Hato.jpg
Belgrade Observatory[13] Belgrade, Kingdom of Serbia Belgrade, Serbia 65 cm (25.6") 10.55 m 1932 Zeiss made lens, same as at Berlin Observatory Pavilion of Large Refractor.JPG
Hida Observatory Gifu, Japan - 65 cm (25.6") 10.5 m 1972
65 cm Zeiss Refractor, Pulkovo observatory Germany[14] Saint Petersburg, Russia 65 cm (25.6") 10.413 m 1954 War reparation from Germany[14] In Pulkovo since 1954. Pulkovo refractor.jpg
Observatory History Museum Mitaka 65 cm Mitaka, Tokyo, Japan - 65 cm (25.6") 10.21 m 1929 Carl Zeiss Jena NAOJ-mitaka-65cm-refractor-dome.jpg
Berlin-Babelsberg Observatory
Berliner Sternwarte Babelsberg
Berlin, Germany 65 cm (26") 10.12 m (33 ft) 1914 Berlin Observatory just moved to Potsdam-Babelsberg in 1913; Zeiss lens Berliner Sternwarte Babelsberg.jpg
Newall Refractor[15]
National Observatory of Athens
UK Athens, Greece since 1957 62.5 cm (24.5") 8.86 m (29 ft) 1869 Built by Thomas Cooke for Robert Stirling Newall. First located at his estate; donated and relocated to Cambridge Observatory in 1889; donated to Athens Observatory and relocated to Mt. Penteli in Greece in 1957. Currently used only for educational purposes as part of the visitor center.
Craig telescope Wandsworth Common, London Dismantled 1857 61 cm (24") 24.5 m (80 ft) 1852 Problem with lens figuring[16] The Family tutor (1851) (14740915186).jpg
Sproul Observatory Pennsylvania, USA Dismantled July 2017 61 cm (24") 11.0 m (36 ft) 1911 Currently under restoration to be re-installed in Northwest Arkansas[17] Sproul Telescope.png
Lowell Observatory Arizona, USA - 61 cm (24") 9.75 m (32 ft) 1894 Alvan Clark & Sons telescope Clark dome.jpg
Einstein Tower[18] Potsdam, Germany - 60 cm (23.6") 14 m 1924 Tower telescope, fixed lens fed by a heliostat Einsteinturm 7443.jpg
Zeiss Double Refractor
Bosscha Observatory
Bandung, Dutch East Indies Bandung, Indonesia 60 cm (23.6") 10.7 m 1928 Bosscha 2003.jpg
Großer Refraktor (Great Refractor)[19]Hamburg Observatory Bergedorf, Germany - 60 cm (23.6") 9 m 1911 by Repsold and Sons, optics (visual + photographic lens) by Steinheil Bdstern 1.jpg
Grubb Parsons Double Refractor Saltsjöbaden, Sweden - 60 + 50 cm (23.6" + 19.7") 8.0 m 1930 Stockholm Observatory in Saltsjöbaden
Radcliffe Double Refractor
UCL Observatory
Oxford, UK Mill Hill, London 60 + 45 cm (23.6" + 18") 7.0 m 1901 Obtained from the Radcliffe Observatory and installed at UCLO (then known as "ULO") in 1938 Radcliffe telescope, University of London Observatory.jpg
Halstead Observatory Princeton, USA Roper Mountain Science Center,[20] Greenville, SC 58.4 cm (23") 9.8 m (32 ft) 1881 by Alvan Clark & Sons
Chamberlin Observatory Colorado, USA - 50 cm (20") 8.5 m (28 ft) 1891 First Light 1894 Chamberlin Observatory Denver, CO.jpg
Chabot Observatory Oakland, California Oakland, California, USA (2000) 50 cm (20") 8.5 m (28 ft) 1914 "Rachel", Warner & Swazey Company (Optics John A Brashear Company) Refurbished in 2000 and moved to present location. Rachel-2-modern.jpg
Van Vleck Observatory Connecticut, USA - 50 cm (20") 8.4 m (27.5 ft) 1922 Vvo.jpg
Carnegie Double Astrograph
Lick Observatory
Mount Hamilton, California, United States Retired? 50 cm (20") x 2 4.67 m (14 ft) 1941/1962 (2nd lens) F7.4 Carnegie telescope dome, Aug 2019.jpg
Merz-Repsold 19 inch telescope
Brera Observatory
Milan, Italy Exposed in Museo Nazionale Scienza e Tecnologia Leonardo da Vinci 49 cm (19.29") 7 m (22.97 ft) 1882 Largest refracting telescope in Italy Telescopio Merz-Repsold di Brera.jpg
Imperial Observatory Straßburg, German Empire Strasbourg, France 48.5 cm (19.1") 7 m (23 ft) 1880[21] Then largest in German Empire Refracting telescope of the Strasbourg observatory.jpg
18½-in Dearborn Observatory Refractor Chicago, USA Evanston, USA 47 cm (18.5") 1862 by Alvan Clark & Sons 2007-04-06 3000x2000 evanston nu observatory.jpg
Luneta 46
Observatório Nacional
Rio de Janeiro, Brazil - 46 cm (18.4") 9.7 m 1921 T. Cooke & Sons[22][23] Observatório Nacional - Rio de Janeiro, Brasil (4118152607).jpg
Wilder Observatory Amherst College, Amherst, Massachusetts, USA - 46 cm (18") (25 ft) 1903 by Alvan Clark & Sons Wilder obsv.jpg
Flower Observatory Philadelphia, USA Dark Sky Project, Lake Tekapo, New Zealand 46 cm (18") 6.7 m (22.6 ft) 1894 by John Brashear From 2016 operational at Lake Tekapo, New Zealand.
Royal Observatory Cape Colony, British Empire South Africa 46 cm (18") 6.7 m (22.6 ft) 1897 [24]
Cooke-Zeiss Refractor,
Royal Observatory of Belgium[25]
Uccle, Belgium - 45 cm (17.7") 6.99 m 1891/1932 by Cooke & Sons, original 38 cm lens by Merz
replaced by 45 cm lens from Zeiss 1932
Gran Ecuatorial Gautier Telescope
La Plata Astronomical Observatory
La Plata, Argentina - 43.3 cm (17") 9,7 m 1894 Gautier Telescopio refractor Gran Ecuatorial Gautier en La Plata.jpg
Brashear Refractor, Goodsell Observatory Northfield, Minnesota, USA - 41.15 cm (16.2") 1890 by John Brashear
Herget Telescope
Cincinnati Observatory
Cincinnati, Ohio - 40.64 cm (16") 1904 by Alvan Clark & Sons Cincinnati Observatory.JPG
Vatican Observatory Castel Gandolfo, Italy - 40 cm (16") 6.0 m 1881 by Zeiss Vatican Observatory Zeiss Visual Refractor Telescope.jpg
Dorides Refractor[26]
National Observatory of Athens
Athens, Greece Athens, Greece 40 cm (16") 5,08 m 1901 by Gautier[27]
Washburn Observatory Madison, Wisconsin, USA In regular use for education and general public. 39.5 cm (15.56") 6.7 m (22.6 ft) 1881 by Alvan Clark & Sons
Dominion Observatory Refractor
Dominion Observatory
Ottawa, Ontario, Canada Moved to Helen Sawyer-Hogg Observatory (Canada Science and Technology Museum, Ottawa) in 1974[28] 38.1 cm (15") 571.5 cm 1905 Original achromat doublet by John Brashear replaced with apochomat triplet by Perkin-Elmer in 1958. Currently used for education and outreach.
Lunette Arago
Paris Observatory
Paris, France - 38 cm (15") 9 m 1883 by Gautier and Henry brothers Paris-observatoirelunettebrünner.jpg
Double Refractor
Fabra Observatory
Barcelona, Spain - 38 cm + 38 cm (15" + 15") 6 m + 4 m 1904 Double telescope
by Mailhat, Paris
Fabra Observatory Refractor.jpg
Gran Ecuatorial Observatorio Astronómico Nacional Tacubaya, México - 38 cm (15") 4.8 m 1885 by Howard Grubb
Harvard Great Refractor
Harvard College Observatory[29]
Cambridge, Massachusetts, USA - 38 cm (15") 6.9 m 1847 largest telescope in America for 20 years[30] Great Refractor.jpg
Merz & Mahler Refractor, Pulkovo observatory Saint Petersburg, Russian Empire Rescued to Leningrad city in WWII (?) 38 cm (15") 6.9 m 1839 (original) twin of the Harvard Great Refractor[29]
Lunette coudée
Lyon Observatory
Saint-Genis-Laval, France - 36.6 cm 7.66 m 1887 Equatorial coudé by Maurice Loewy Observatoire Lyon Coudee.JPG
Telescopio Amici
Osservatorio Astrofisico di Arcetri
Florence, Italy - 36 cm 5 m 1872 28 cm lens by G. B. Amici substituted by Zeiss lens in 1926. Currently used only for educational purposes.
Photographic Refractor
Leiden Observatory
Leiden, Netherlands - 34 cm + 15 cm (13.4" + 5.9") 524 cm 1897 Double telescope
by Gautier and Henry brothers
Astrograph
Vienna Observatory
Vienna, Austrian Empire Vienna, Austria 34 cm + 26 cm (13.3" + 10.2") 3.4 m + 3.4 m 1885 Double telescope
by Steinheil
Perth Astrograph, Perth Observatory[31] Old Perth Observatory, Mount Eliza, Western Australia Perth Observatory, Bickley, Western Australia. Used for public education and outreach 33 cm (13") 3.34 m 1897 Designed and built by Howard Grubb & Co. Relocated to Bickley ~1966. The original telescope (both camera and guide scopes), mount and dome were re-erected at Bickley
Fitz-Clark Refractor
Allegheny Observatory, University of Pittsburgh
Pittsburgh, Pennsylvania, United States - 32.02 cm (13") 4.62 1861 Fitz made, visual/photographic. In 1895 established that Saturn's Rings are made up of particles and not solid.[7] Allegheny Observatory 2007a.jpg
H. Fitz-H.G. Fitz Refractor
Henry Ruthurfurd, Private Observatory
New York City , United States - 32.02 cm (13") 4.62 1864 Fitz made, visual/photographic. Started by Henry, finished by son Henry Giles
Bamberg Refractor
Urania Observatory (Berlin)
Berlin-Moabit, Prussia Berlin, Germany 31.4 cm (12.36") 5 m 1889 then biggest in Prussia, moved to Insulaner Wilhelm Foerster Observatory in 1963[32] Bamberg-Refraktor.P1139429.jpg
H. Fitz 12.6" refractor

Detroit Observatory in Ann Arbor

Ann Arbor, Michigan, USA 32 cm (12⅝") 508 cm (200") 1857 The telescopes were restored to functionality as part of the University of Michigan's 2009 International Year of Astronomy celebration. Viewing nights and open houses[33] have been running since then. 12.6" Fitz telescope in Ann Arbor.jpg
Grubb refractor, Keele Observatory[34] Oxford, England Keele University, England (since 1962),

in use for the public

31.0 cm (12.25") 4.39 m 1874 Still awaiting the reunion with its 19th-century camera used in the Carte du Ciel project and to prove Einstein's general relativity theory during the 1919 solar eclipse. KeeleOxford.jpg
South Telescope, Dunsink Observatory Dublin, Ireland Dublin, Ireland 30 cm (12") 1868 by Grubb, the telescope is still used for various outreach activities
Northumberland Telescope,[35] Institute of Astronomy, Cambridge University Cambridge, England Still in use by Cambridge University Astronomical Society and Cambridge Astronomical Association 30 cm (12") 5.95m 1833 Original lens 11.6" made by Cauchoix of Paris, replaced on 150th anniversary by 12" lens designed by R.V. Willstrop,[36] and made by A.E. Optics of Cambridge.[37] Northumberland Telescope Dome - geograph.org.uk - 370647.jpg
Urania Sternwarte (Zurich) Zurich, Switzerland - 30 cm (12") 5.05 m 1907 by Zeiss Zürich - Lindenhof - Urania-Sternwarte - Kuppel IMG 1911.JPG
Griffith Observatory Los Angeles - 30 cm (12") 5.03 m 1931 by Zeiss ග්‍රිෆිත් දුරේක්‍ෂය.JPG
Clark-Refraktor[38]
Vienna Observatory
Vienna, Austrian Empire Vienna, Austria 30 cm (12") 5.06 m 1880 by Clark and Sons
Deutsches Museum Munich, Germany - 30 cm (12") 5.0 m 1924 by Zeiss Deutsches Museum Munich 2014 02.jpg
Ladd Observatory,
Brown University
Providence, Rhode Island, United States Still in use for instruction and public education 30 cm (12") 4.6 m (15 ft) 1891 Lens designed by Charles S. Hastings and made by John Brashear; telescope mount by George N. Saegmuller Ladd Observatory telescope.jpg
Irving Porter Church Memorial Telescope
Fuertes Observatory, Cornell University
Ithaca, New York Still used for instruction and public outreach. 30 cm (12") 4.57 m (15 ft) 1922 Optics by John Brashear, mounting by Warner & Swasey. Irving Porter Church Telescope.jpg
Jewett Observatory Pullman, Washington, USA Used for instruction and pleasure 30 cm (12") 4.57 m (15 ft) Assembled from older parts 1953[39] Alvan Clark & Sons Jewett Observatory 01-04-15.jpg
Silesian Planetarium and Astronomical Observatory Katowice/Chorzów, Silesia, Poland 30 cm (12")[40] 4.5 m 1955 Largest and oldest Planetarium and Astronomical Observatory in Poland.[41] The 3rd largest in Eastern Europe (east of Germany), after Pulkovo Observatory in Saint Petersburg, Russia and Belgrade Observatory in Belgrade, Serbia Planetarium WPKiW.jpg
University of Illinois Observatory Urbana, Illinois, USA Used for instruction and pleasure 30 cm (12") 4.57 m (15 ft) 1896 by John Brashear, National Historic Landmark, still used for instruction Champaign-Urbana area IMG 1138.jpg
Equatorial Refractor
Sydney Observatory
Sydney, Australia Still in use for education and public outreach 28.956cm (11.4") - 1874 by Hugo Schroeder, used to view transit of Venus that occurred on 9 December 1874 Schroeder telescope in use.jpg
Mitchel Telescope
Cincinnati Observatory
Cincinnati, Ohio, USA - 28 cm (11") 1843 Merz & Mahler; Oldest professional telescope still used weekly by the public[42] Refractor Cincinnati observatory.jpg
Brashear Refractor
Nicholas E. Wagman Observatory
Pittsburgh, Pennsylvania, USA - 28 cm (11") 1910 John Brashear, Amateur Astronomers Association of Pittsburgh[43]
Great Refractor
Kuffner Observatory
Vienna, Austria - 27 cm + 15.6 cm
(10.6" + 6.1")
350 cm + 294 cm 1884 + 1890 Double telescope
by Repsold and Sons, optics by Steinheil
Kuffner Observatory Refractor.jpg
Repsold Refractor (10-duims)
Leiden Observatory
Leiden, Netherlands - 26.6 cm (10.5") 399,5 cm 1885 Repsold and Sons, optics by Alvan Clark & Sons
Äquatoreal (Equatorial)[44]
Hamburg Observatory
Millerntor Observatory, Hamburg, Germany Hamburg Observatory, Bergedorf, Germany 26 cm (10.2") 3 m 1867 Repsold and Sons, optics by G. & S. Merz
Hume Cronyn Memorial Observatory Western University
London, Ontario, Canada
- 25.4 cm (10") 4.386 m (172") 1940 by Perkin-Elmer Corp. Glass from Chance Brothers. Cronyn Observatory 254mm refractor.jpg
Mills Observatory Dundee, Scotland (1951) 25 cm (10")   1871 by T. Cooke & Sons. Training telescope at St. Andrews 1938–1951 The 10-inch Cooke Refractormills.jpg
Coats Observatory Paisley, Scotland (1898) 25 cm (10")   1898 by Howard Grubb. Replaced 5" refractor by Thomas Cooke, installed in 1883. Grubb-Telescope.jpg
Blackett Observatory Marlborough College
Wiltshire, England
- 25 cm (10")   1860 by Thomas Cooke. -
Quito Astronomical Observatory Quito La Alameda park 24 cm (9.6") 1875 An operational 1875 Merz telescope and one of the Oldest Observatories in South America, founded in 1873. Antique Telescope at the Quito Astronomical Observatory 002.JPG
Fraunhofer Refractor, United States Naval Observatory (Foggy Bottom) Foggy Bottom, D.C., USA 24.4 cm (9.6") 1844 [45]
Fraunhofer-Refraktor
Berlin Observatory
Berlin-Kreuzberg, Deutsches Kaiserreich Moved 1913 to Munich, Germany 24 cm (9.6") 4 m (13.4′) 1835 Used to discover Neptune; in Deutsches Museum, München since 1913[46] Sternwarte Berlin Schinkel.jpg
Great Dorpat Refractor (Fraunhofer)
Dorpat/Tartu Observatory (Old Building)
Dorpat, Governorate of Livonia Tartu, Estonia 24 cm (9.6") 4 m (13.4′) 1824 "...the first modern, achromatic, refracting telescope."[47][48] Tartu tähetorn 2006.jpg

See also

References

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Further reading