Source: https://aidb.si/d/largest-optical-telescopes — From Wikipedia, CC BY-SA 4.0: "List of largest optical reflecting telescopes" (https://en.wikipedia.org/wiki/List_of_largest_optical_reflecting_telescopes), by Wikipedia contributors. Wikidata identifiers are CC0.
| ID | Telescope | Wikidata | Aperture (m) | Mirror type | Mirror detail | Nationality / sponsors | Site | First light | Later change |
|---|---|---|---|---|---|---|---|---|---|
| large-binocular-telescope-lbt | Large Binocular Telescope (LBT) | Q845304 | 11.9 | Multiple | Two 8.4 m (331 in) mirrors | USA, Italy, Germany | Mount Graham International Observatory, Arizona, USA | 2005 | |
| gran-telescopio-canarias-gtc | Gran Telescopio Canarias (GTC) | Q59973 | 10.4 | Segmented | 36 hexagonal segments | Spain, Mexico, USA | Roque de los Muchachos Obs., Canary Islands, Spain | 2006 | |
| hobby-eberly-telescope-het | Hobby–Eberly Telescope (HET) | Q139605 | 10 | Segmented | 91 × 1 m (39 in) hexagonal segments forming an 11 m × 9.8 m mirror | USA, Germany | McDonald Observatory, Texas, USA | 1997 | Aperture increased 2015 |
| keck-1 | Keck 1 | Q210997 | 10 | Segmented | 36 hexagonal segments | USA | Mauna Kea Observatories, Hawaii, USA | 1993 | |
| keck-2 | Keck 2 | Q210997 | 10 | Segmented | 36 hexagonal segments | USA | Mauna Kea Observatories, Hawaii, USA | 1996 | |
| southern-african-large-telescope-salt | Southern African Large Telescope (SALT) | Q833639 | 9.2 | Segmented | 91 × 1 m (39 in) hexagonal segments forming an 11 m × 9.8 m mirror | South Africa, USA, UK, Germany, Poland, New Zealand | South African Astronomical Obs., Northern Cape, South Africa | 2005 | |
| subaru-jnlt | Subaru (JNLT) | Q841079 | 8.2 | Single | Japan | Mauna Kea Observatories, Hawaii, USA | 1999 | ||
| vlt-ut1-antu | VLT UT1 – Antu | Q265628 | 8.2 | Single | ESO Countries, Chile | Paranal Observatory, Antofagasta Region, Chile | 1998 | ||
| vlt-ut2-kueyen | VLT UT2 – Kueyen | Q265628 | 8.2 | Single | ESO Countries, Chile | Paranal Observatory, Antofagasta Region, Chile | 1999 | ||
| vlt-ut3-melipal | VLT UT3 – Melipal | Q265628 | 8.2 | Single | ESO Countries, Chile | Paranal Observatory, Antofagasta Region, Chile | 2000 | ||
| vlt-ut4-yepun | VLT UT4 – Yepun | Q265628 | 8.2 | Single | ESO Countries, Chile | Paranal Observatory, Antofagasta Region, Chile | 2001 | ||
| gemini-north-gillett | Gemini North (Gillett) | Q744667 | 8.1 | Single | USA, UK, Canada, Chile, Australia, Argentina, Brazil | Mauna Kea Observatories, Hawaii, USA | 1999 | ||
| gemini-south | Gemini South | Q744667 | 8.1 | Single | USA, UK, Canada, Chile, Australia, Argentina, Brazil | Cerro Pachón (CTIO), Coquimbo Region, Chile | 2001 | ||
| james-webb-space-telescope | James Webb Space Telescope | Q186447 | 6.5 | Segmented | 18 hexagonal segments | NASA, ESA, CSA | Halo orbit around the Earth-Sun L2 Point | 2022 | |
| mmt-current-optics | MMT (current optics) | Q779895 | 6.5 | Single | USA | F. L. Whipple Obs., Arizona, USA | 2000 | ||
| magellan-1-walter-baade | Magellan 1 (Walter Baade) | Q1541020 | 6.5 | Single | USA | Las Campanas Obs., Atacama Region, Chile | 2000 | ||
| magellan-2-landon-clay | Magellan 2 (Landon Clay) | Q1541020 | 6.5 | Single | USA | Las Campanas Obs., Atacama Region, Chile | 2002 | ||
| tokyo-atacama-observatory-tao | Tokyo Atacama Observatory (TAO) | Q652811 | 6.5 | Single | Japan | Cerro Chajnantor, Atacama Desert, Chile | 2024 | ||
| simonyi-survey-telescope | Simonyi Survey Telescope | Q672021 | 6.4 | Combined | primary & tertiary mirror Total diameter 8.4 m (331 in) | USA | Vera C. Rubin Observatory, Coquimbo Region, Chile | 2025 | |
| bta-6 | BTA-6 | Q787671 | 6 | Single | USSR/Russia | Special Astrophysical Obs., Karachay–Cherkessia, Russia | 1975 | ||
| large-zenith-telescope-lzt | Large Zenith Telescope (LZT) | Q1805929 | 6 | Liquid | Canada, France, United States | Maple Ridge, British Columbia, Canada | 2003 | Decommissioned 2016 | |
| hale-telescope | Hale Telescope | Q2471197 | 5.08 | Single | USA | Palomar Observatory, California, USA | 1949 | ||
| lamost | LAMOST | Q1513326 | 4.9 | Segmented | 37 segments for the 6.67 m × 6.05 m primary and 24 segments for the 5.72 m × 4.40 m corrector; effective aperture 3.6–4.9 m | China | Beijing Astronomical Obs., Xinglong, China | 2008 | |
| mmt-original-optics-see-above-for-current-version | MMT (original optics) (see above for current version) | Q779895 | 4.7 | Multiple | Six 1.8 m (71 in) mirrors | USA | F. L. Whipple Obs., Arizona, USA | 1979 | Mirrors removed 1998 |
| lowell-discovery-telescope | Lowell Discovery Telescope | Q1383460 | 4.3 | Single | USA | Lowell Observatory, Happy Jack, Arizona, USA | 2012 | ||
| william-herschel-telescope | William Herschel Telescope | Q541505 | 4.2 | Single | UK, Netherlands, Spain | Roque de los Muchachos Obs., Canary Islands, Spain | 1987 | ||
| soar | SOAR | Q787525 | 4.1 | Single | USA, Brazil | Cerro Pachón (CTIO), Coquimbo Region, Chile | 2002 | ||
| vista | VISTA | Q612291 | 4.1 | Single | ESO Countries, Chile | Paranal Observatory, Antofagasta Region, Chile | 2009 | ||
| victor-m-blanco-telescope | Víctor M. Blanco Telescope | Q7944666 | 4 | Single | USA | Cerro Tololo Inter-American Obs., Coquimbo Region, Chile | 1976 | ||
| international-liquid-mirror-telescope | International Liquid Mirror Telescope | Q112861106 | 4 | Liquid | Belgium, Canada, India, Poland | ARIES Devasthal Observatory, Nainital, India | 2022 | ||
| nicholas-u-mayall-4-m | Nicholas U. Mayall 4 m | Q3546489 | 4 | Single | USA | Kitt Peak National Obs., Arizona, USA | 1973 | ||
| daniel-k-inouye-solar-telescope | Daniel K. Inouye Solar Telescope | Q2825377 | 4 | Single | USA | Haleakala Observatory, Hawaii, USA | 2019 | ||
| dag-telescope | DAG Telescope | Q6032929 | 4 | Single | Turkey | Eastern Anatolia Observatory, Erzurum, Turkey | 2025 | ||
| anglo-australian-telescope-aat | Anglo-Australian Telescope (AAT) | Q2632045 | 3.89 | Single | Australia, UK | Australian Astronomical Obs., New South Wales, Australia | 1974 | ||
| united-kingdom-infrared-telescope-ukirt | United Kingdom Infrared Telescope (UKIRT) | Q848021 | 3.8 | Single | UK, United States | Mauna Kea Observatories, Hawaii, USA | 1979 | ||
| 3-67-m-aeos-telescope-aeos | 3.67 m AEOS Telescope (AEOS) | Q4634267 | 3.67 | Single | USA | Air Force Maui Optical Station, Hawaii, USA | 1996 | ||
| 3-6-m-devasthal-optical-telescope-dot | 3.6 m Devasthal Optical Telescope (DOT) | Q24949537 | 3.6 | Single | India | ARIES Devasthal Observatory, Nainital, India | 2016 | ||
| telescopio-nazionale-galileo-tng | Telescopio Nazionale Galileo (TNG) | Q16269 | 3.58 | Single | Italy | Roque de los Muchachos Obs., Canary Islands, Spain | 1997 | ||
| new-technology-telescope-ntt | New Technology Telescope (NTT) | Q1982969 | 3.58 | Single | ESO countries | La Silla Observatory, Coquimbo Region, Chile | 1989 | ||
| canada-france-hawaii-telescope-cfht | Canada-France-Hawaii Telescope (CFHT) | Q1031946 | 3.58 | Single | Canada, France, USA | Mauna Kea Observatories, Hawaii, USA | 1979 | ||
| eso-3-6-m-telescope | ESO 3.6 m Telescope | Q74784 | 3.57 | Single | ESO countries | La Silla Observatory, Coquimbo Region, Chile | 1977 | ||
| mpi-caha-3-5-m | MPI-CAHA 3.5 m | Q209610 | 3.5 | Single | West Germany, Spain | Calar Alto Obs., Almería, Spain | 1984 | ||
| usaf-starfire-3-5-m | USAF Starfire 3.5 m | Q2332743 | 3.5 | Single | USA | Starfire Optical Range, New Mexico, USA | 1994 | ||
| wiyn-telescope | WIYN Telescope | Q7951025 | 3.5 | Single | USA | Kitt Peak National Obs., Arizona, USA | 1994 | ||
| space-surveillance-telescope | Space Surveillance Telescope | Q1418160 | 3.5 | Single | USA, Australia | White Sands Missile Range, New Mexico, United States Relocated to Harold E. Holt Naval Communication Station, Western Australia, Australia | 2011 | Relocated 2020 | |
| astrophysical-research-consortium-arc | Astrophysical Research Consortium (ARC) | Q616529 | 3.48 | Single | USA | Apache Point Obs., New Mexico, USA | 1994 | ||
| iranian-national-observatory-ino340 | Iranian National Observatory (INO340) | Q5931793 | 3.4 | Single | Iran | Mount Gargash, Isfahan Province, Iran | 2022 | ||
| shane-telescope | Shane Telescope | Q5006395 | 3.05 | Single | USA | Lick Observatory, California, USA | 1959 | ||
| nasa-infrared-telescope-facility | NASA Infrared Telescope Facility | Q1662664 | 3 | Single | USA | Mauna Kea Observatory, Hawaii, USA | 1979 | ||
| nasa-lmt | NASA-LMT | Q126192277 | 3 | Liquid | USA | NASA Orbital Debris Obs., New Mexico, USA | 1995 | Decommissioned 2002 |