List of largest infrared telescopes
The largest infrared telescopes for infrared astronomy are listed in terms of diameter of primary mirror. The infrared spectrum with its longer wavelength than visible light has a number of challenges, especially for ground-based observatories but also in space. Notably infrared radiation is emitted by all physical objects above Absolute Zero temperature so telescopes are subject to local interference.
Overall
Infrared observations from Earth's surface are possible in a limited way but can be very dependent on location and atmospheric conditions. Water vapour in the Earth's atmosphere blocks much of the infrared band, although some limited observations are possible and there is a number of infrared observatories.Sometimes other optical telescopes can make infrared observations if they are equipped with the right detectors, even if they are not dedicated infrared observatories. For ground-based observatories, the location can make a big difference in how much observation is possible.
| Name | Image | Effective aperture | Wavelength Coverage | Site | Year | Refs |
| TAO telescope | 0.9-38 μm | University of Tokyo Atacama Obs., Chile | 2024 | |||
| James Webb Space Telescope | 0.6-28.5 μm | Space, Sun-Earth L2 | 2022- | |||
| VISTA | 0.85 – 2.3 μm | Paranal Obs., Chile | 2008 | |||
| Eastern Anatolia Observatory | 0.9 – 2.5 μm | Erzurum, Turkey | 2024 | |||
| United Kingdom Infrared Telescope | 0.8 - 20 μm | Mauna Kea Obs., Hawaii | 1978 | |||
| Herschel Space Observatory | 60-672 μm | Space, Sun-Earth L2 | 2009-2013 | |||
| Infrared Telescope Facility | 0.8 - 25 μm | Mauna Kea, Hawaii | 1979 | |||
| SOFIA | 0.3 - 655 μm | 747SP; Stratosphere | 2010-2022 | |||
| Wyoming Infrared Observatory | 0.4 - 0.8 μm | Jelm mountain, 9656 ft. | 1977 |
Space telescopes only
| Name | Effective aperture cm | Wavelength Coverage | Year | Refs |
| James Webb (JWST) | 650 cm | 0.6-28.5 μm | 2021- | |
| Herschel Obs. | 350 cm | 60-672 μm | 2009 - 2013 | |
| Hubble Wide [Field Camera 3|WFC3] | 240 cm | 0.2-1.7 μm | 2009 - | |
| Euclid NISP | 120 cm | 0.92-2.02 μm | 2023 - | |
| Spitzer | 85 cm | 3-180 μm | 2003 - 2020 | |
| Akari | 68.5 cm | 2-200 μm | 2006 -2011 | |
| ISO | 60 cm | 2.5-240 μm | 1995-1998 | |
| IRAS | 57 cm | 5-100 μm | 1983 | |
| NEO Surveyor | 50 cm | 4–5.2 & 6–10 μm | 2028 | |
| WISE/NEOWISE | 40 cm | 3-25 μm | 2009-2011 & 2013 - | |
| MSX | 33 cm | 4.3-21 μm | 1996 - 1997 | |
| SPHEREx | 20 cm | 0.75 to 5.0 μm | 2025 - | |
| Spacelab IRT | 15.2 cm | 1.7-118 μm | 1985 Aug |