List of proposed space observatories
This list contains proposals for space telescopes, space-based (situated in space) astronomical observatories. The list of proposed space observatories is a list containing examples of past and present space observatory plans, concepts, and proposals. For observatories in orbit, see list of space telescopes. Unlike that list, this list includes concept and proposals that were not and in all likelihood will not ever be launched as they may have been cancelled or were only ever proposals.
Proposed space observatories
Active in this list means it is still under consideration for development, not that it is in orbit
- Merged, Cancelled, Superseded
- Advanced Telescope for High Energy Astrophysics (ATHENA)
- Big Bang Observer
- CHEOPS (selected for launch)
- Deci-hertz Interferometer Gravitational wave Observatory (DECIGO)
- Fast INfrared Exoplanet Spectroscopy Survey Explorer (FINESSE)
- Gravity and Extreme Magnetism (GEMS)
- LOFT - Large Observatory For X-ray Timing
- Nautilus Deep Space Observatory
- Near-Earth Object Camera (NEOcam)
- Planetary Dynamics Explorer
- PLATO (selected for launch)
- Space Infrared Telescope for Cosmology and Astrophysics (SPICA)
- Telescope for Habitable Exoplanets and Interstellar/Intergalactic Astronomy (THEIA)
- Waypoint 1. 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
Various proposals or concepts for high-energy light observatories (circa 2010s):
- AdEPT: Advanced Energetic Pair Telescope: pair production telescope concept for gamma-ray polarimetry
- AEGIS: Astrophysics Experiment for Grating and Imaging Spectroscopy, soft X-ray spectrometer.
- APT: Advanced Pair Telescope
- Arcus, X-ray spectrometer concept for International Space Station
- ASCOT: Advanced Scintillator Compton Telescope
- A-STAR: All-Sky Transient Astrophysics Explorer
- Athena, an X-ray observatory
- AXSIO: Advanced X-ray Spectroscopic Imaging Observatory
- AXTAR: Advanced X-Ray Timing Array, X-ray timing mission
- BEST: Black Hole Evolution and Space-Time Observatory (include deep hard X-ray imaging (5 – 70 keV))
- BHI: Black Hole Imager
- Black Hole Finder
- CASTER: Coded Aperture Survey Telescope for Energetic Radiation
- EDGE: Explorer of Diffuse emission and Gamma ray burst Explosions
- EPE: Extreme Physics Explorer
- EREXS: Epoch of Reionization Energetic X-ray Survey
- EXIST: Energetic X-ray Imaging Survey Telescope
- Gen-X: The Generation X-Ray Mission
- GRAVITAS: General Relativistic Astrophysics Via Timing and Spectroscopy
- HEX-P: High-Energy X-ray Probe
- IXPE: Imaging X-ray Polarimetry Explorer (to launch in 2021)
- MIRAX: Monitor e Imageador de Raios X
- NHXM: New Hard X-ray Mission
- PheniX, focussing X-ray telescope concept
- PRAXyS: Polarimetry of Relativistic X-ray Sources
- SAHARA: Spectral Analysis with High Angular Resolution Astronomy
- SMART-X: Square Meter, Arcsecond Resolution X-ray Telescope
- Tsubame, micro-satellite for X-ray polarimetry
- WhimEx: Warm-Hot Inter-Galactic Medium Explorer
- WFXIS: Wide-Field X-ray Imaging Spectrometer
- WFXT: Wide-Field X-ray Telescope
- Xenia: a Probe of Cosmic Chemical Evolution
- XIPE: the X-ray Imaging Polarimetry Explorer (ESA)
- X-Ray Surveyor
Additional examples and non-space telescopes
For launch in the 2030s, NASA is evaluating four possible designs: the Origins Space Telescope, Lynx X-ray Surveyor, Habitable Exoplanet Imaging Mission (HabEx), and Large Ultraviolet-Optical-Infrared Surveyor (LUVOIR).
One concept idea is for a 20–30 meter telescope created with balloon in a sub-orbital but extreme high altitude location. 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 (LBR) (sub-orbital version)
- Space-based Large Balloon Reflector (LBR)
- TeraHertz Space Telescope (TST)
Artist's impression of the Laser Interferometer Space Antenna
Artist's impression of the SIM Lite Astrometric Observatory
NASA conception of IXO
- Concept design of the LiteBIRD satellite for CMB B-mode polarization. Y. Sekimoto; P. Ade; K. Arnold; J. Aumont; J. Austermann, etal. Proceedings Volume 10698, Space Telescopes and Instrumentation 2018: Optical, Infrared, and Millimeter Wave; 106981Y (2018) doi:10.1117/12.2313432 Event: SPIE Astronomical Telescopes + Instrumentation, 9 August 2018, Austin, Texas, United States.
- "Advanced Technology Large-Aperture Space Telescope". Space Telescope Science Institute. Retrieved 2010-10-08.
- "KEUS – The X-Ray Evolving Universe Spectroscopy Mission". ESA. Retrieved 2008-02-28.
- "Official NASA IXO Home Page". NASA. Retrieved 2008-02-28.
- "SIM Lite JPL". NASA. Archived from the original on 2007-01-16. Retrieved 2009-03-19.
- "ESA Science & Technology: Darwin". ESA. Retrieved 2008-02-28.
- "Planet Quest: Missions – Terrestrial Planet Finder". NASA. Archived from the original on 2008-02-18. Retrieved 2008-03-03.
- "Dark Universe Observatory". Sonoma State University. Archived from the original on 2004-12-05. Retrieved 2008-02-29.
- "Dark Universe Observatory – About the Launch Vehicle and Orbit". Sonoma State University. Archived from the original on 2004-12-05. Retrieved 2008-02-29.
- "Destiny JDEM Mission Public Page". National Optical Astronomy Observatory. Retrieved 2008-02-28.
- "$1.6 Billion Telescope Would Search Alien Planets and Probe Dark Energy". SPACE. Retrieved 2010-10-09.
- "Astro2010 Report Release Presentation". NASA. Archived from the original (PDF) on 2011-07-26. Retrieved 2010-10-09.
- "NASA Introduces New, Wider Set of Eyes on the Universe" (Press release). 2016-02-18. Retrieved 2016-02-18.
- "Isro plans to launch India's 2nd space observatory".
- "NASA – NSSD – Spacecraft – Trajectory Details (Astromag FF)". NASA. Retrieved 2008-02-27.
- "NASA – NSSDC – Spacecraft – Details (Astromag-F)". NASA. Retrieved 2008-02-27.
- "VSOP-2 project". JAXA. Retrieved 2008-02-28.
- "EXCEDE Home Page". University of Arizona. Retrieved 2012-02-23.
- "EXCEDE the Search for Planets". Astrobiology magazine. Retrieved 2012-02-23.
- LISA Consortium. "LISA: Laser Interferometer Space Antenna" (PDF). Retrieved 29 January 2017.[permanent dead link]
- "WSO-UV". Wso-uv.org. Archived from the original on 27 September 2011. Retrieved 11 August 2017.
- "China's Answer To The Hubble Telescope". Popular Science. March 11, 2016.
- Hatfield, Miles (2 August 2019). "Shining (Star)light on the Search for Life". NASA. Retrieved 3 August 2019.
- NASA (2 August 2019). "News Relese 2-Aug-2019 - Shining (star)light on the search for life". EurekAlert!. Retrieved 3 August 2019.
- "SAFIR - Technologies". safir.jpl.nasa.gov. Archived from the original on 2013-02-16. Retrieved 11 August 2017.
- University of Arizona (2 August 2019). "A new lens for life-searching space telescopes - University of Arizona researchers have designed a new kind of telescope that is a cheaper, lighter and more powerful option than creating telescopes using ever-larger mirrors. With a fleet of the newly designed space telescopes, they aim to scour a thousand potentially earth-like planets for signs of life". EurekAlert!. Retrieved 5 August 2019.
- "A Thousand Earths: A Very Large Aperture, Ultralight Space Telescope Array for Atmospheric Biosignature Surveys". The Astronomical Journal. 158 (2). 29 July 2019. doi:10.3847/1538-3881/ab2631. Retrieved 5 August 2019.
- Apai, D.; et al. (2018). "Nautilus DeepSpace Observatory: A Giant Segmented Space Telescope Array for a Galactic Biosignature Survey" (PDF). Universities Space Research Association. Retrieved 5 August 2019.
- "M. Wong , et al. – A Dedicated Space Observatory for Time-domain Solar System Science" (PDF). Lpi.usra.edu. Retrieved 11 August 2017.
- "NASA Considers Sending a Telescope to Outer Solar System - Universe Today". Universitytoday.com. 19 December 2011. Retrieved 11 August 2017.
- "ZEBRA". Zebra.caltech.edu. Archived from the original on 23 September 2012. Retrieved 11 August 2017.
- "Concepts for Future High Energy Astrophysics Future Missions". heasarc.gsfc.nasa.gov. Retrieved 11 August 2017.
- Scoles, Sarah. "NASA Considers Its Next Flagship Space Telescope". Scientific American. Retrieved 2016-03-31.
- Hall, Loura (3 May 2016). "Ballooning Expectations: New Approach for Astronomy". Nasa.gov. Retrieved 11 August 2017.