List of proposed space telescopes
This list contains proposals for space telescopes, space-based astronomical observatories. It is a list of past and present space observatory plans, concepts, and proposals. For observatories in orbit, see list of space telescopes. Unlike that list, this one includes concepts and proposals that are unlikely ever to be launched, as they may have been cancelled or were only proposals.
Space observatories under development
| Name | Agency | Type | Proposed launch date | Status | Proposed location | Ref |
| TOLIMAN | NASA | visible | 2026 | under construction | Low Earth orbit | |
| Xuntian | CNSA | ultraviolet, visible, infrared | 2026 | under construction | Low Earth orbit | |
| PLATO | ESA | visible | 2026 | under construction | Sun-Earth L2 Lagrange point | |
| ULTRASAT | ISA | ultraviolet | 2026 | Geosynchronous orbit | ||
| Nancy Grace Roman Space Telescope | NASA | infrared | October 2026-May 2027 | confirmed and named 2020 | Sun-Earth L2 Lagrange point | |
| Compton Spectrometer and Imager | NASA | gamma ray | 2027 | Low Earth orbit | ||
| ARIEL | ESA | visible, infrared | 2028 | Sun-Earth L2 Lagrange point | ||
| Lazuli Space Telescope | Schmidt Sciences | visible, near-infrared | 2028 | Proposed, funded | Elliptical orbit | |
| Spektr-UV | Roscosmos | ultraviolet | 2029 | funded | Geosynchronous orbit | |
| UVEX | NASA | ultraviolet | 2030 | Highly elliptical orbit | ||
| LiteBIRD | JAXA | millimeter radio | 2032 | Approved for development | Sun-Earth L2 Lagrange point | |
| AXIS | NASA | X-Ray | 2032 | early planning | Low Earth orbit | |
| PRIMA | NASA | far-infrared | 2032 | early planning | Sun-Earth L2 Lagrange point | |
| Taiji | CNSA/CAS | gravitational waves | 2033 | phase 1 of 3-phase development completed | Heliocentric orbit | |
| Advanced Telescope for High Energy Astrophysics | ESA | x-ray | 2035 | Sun-Earth L2 Lagrange point | ||
| Laser Interferometer Space Antenna | ESA | gravitational waves | 2037 | Approved for development | Solar Earth-trailing orbit | |
| Habitable Worlds Observatory | NASA | Ultraviolet, Visible, Infrared | 2041 | early planning 'Phase 1' | Sun-Earth L2 Lagrange point | |
| X-Ray Great Observatory | NASA | X-Ray | 2047 | early planning 'Phase 1' | possibly Sun-Earth L2 Lagrange point | |
| Far-Infrared Great Observatory | NASA | Far-Infrared | 2051 | early planning 'Phase 1' | possibly Sun-Earth L2 Lagrange point | |
| AstroSat-2 | ISRO | Near Ultraviolet, Far Ultraviolet, Visible | TBD | – | Low Earth orbit | |
| ExoWorlds Mission | ISRO | TBD | ||||
| Indian spectroscopic and imaging space telescope | ISRO | TBD | ||||
| Galileo Solar Space Telescope | INPE | Visible and ultraviolet | TBD | Admission process at AEB | Low Earth orbit or Geostationary orbit |
Additional examples and non-space telescopes
For launch in the 2030s, NASA is evaluating four possible designs: the Origins Space Telescope, Lynx X-ray Observatory, Habitable Exoplanets Observatory, and Large UV Optical Infrared Surveyor.Balloon-borne telescopes have been in use since the 1950s. A 20–30 meter balloon telescope has been suggested. The balloon would be transparent on one side, and have a circular reflecting mirror on the other side. There are two main designs using this principle.
- Large Balloon Reflector
- Space-based Large Balloon Reflector
- *TeraHertz Space Telescope
Additional examples
- Advanced Telescope for High Energy Astrophysics
- Big Bang Observer
- Cosmological Advanced Survey Telescope for Optical and UV Research
- Deci-hertz Interferometer Gravitational wave Observatory
- EChO
- Fast Infrared Exoplanet Spectroscopy Survey Explorer
- Gravity and Extreme Magnetism Small Explorer
- Habitable Exoplanets Observatory, a large UV to NIR focused design, 4 meter mirror
- LOFT - Large Observatory For X-ray Timing
- Large Ultraviolet Optical Infrared Surveyor
- Large Interferometer For Exoplanets
- Nautilus Deep Space Observatory
- Near-Earth Object Surveillance Mission
- PEGASE
- Planetary Dynamics Explorer
- Space Infrared Telescope for Cosmology and Astrophysics
- Telescope for Habitable Exoplanets and Interstellar/Intergalactic Astronomy
- THESEUS
- Waypoint-1 Space Telescope, visible light, UV and hyper-spectral imaging for astrophysical research and ground observation
- Whipple, proposed transit telescope for KBO and Oort objects
- ZEBRA, Zodiacal dust, Extragalactic Background and Reionization Apparatus A small infrared observatory sent out to 10 AU by NASA
- Membrane Space Telescope: A concept of huge reflecting telescopes in space, where the primary mirror would be composed of very thin and lightweight membrane, that would be kept in the required accurate shape by thermal radiative pressure projected from behind. ~15nm RMS precision was achieved in prototype testing.