Ariel

Names| Atmospheric Remote-sensing Infrared Exoplanet Large-survey
Mission type| Space telescope
Operator| European Space Agency
Website| esa.int: Ariel
arielmission.space
Mission duration| 4 years (planned) [1]
Spacecraft properties
Launch mass| 1,300 kg (2,900 lb) [2]
Dry mass| 1,000 kg (2,200 lb)
Payload mass| 300 kg (660 lb)
Start of mission
Launch date| 2031 (planned)[3]
Rocket| Ariane 62
Launch site| Guiana Space Centre,
Kourou, ELA-4
Contractor| Arianespace
Orbital parameters
Reference system| Sun–Earth L2 orbit[1]
Main Cassegrain reflector
Diameter| 1.1 × 0.7 m
Focal length| f/13.4
Collecting area| 0.64 m2
Wavelengths| visible and near-infrared
Instruments
Telescope assembly (TA)
Ariel infrared spectrometer (AIRS)
Fine Guidance System (FGS)

Ariel mission insignia

Cosmic Vision

<- PLATO

EnVision ->

ESA's exoplanet missions

Ariel (Atmospheric Remote-sensing Infrared Exoplanet Large-survey) is a planned space telescope and the fourth medium-class mission of the European Space Agency's Cosmic Vision programme. The mission is aimed at observing at least 1,000 known exoplanets using the transit method, studying and characterising the planets' chemical composition and thermal structures. Compared to the James Webb Space Telescope, Ariel will be a much smaller telescope with more observing time available for planet characterisation. Ariel was expected to be launched in 2029 aboard an Arianespace Ariane 6 together with the Comet Interceptor into the Sun-Earth Lagrange point L2.[4][5][6] However as of January 2026, it is likely to be delayed until 2031.[3]

## Contents

* 1 Background
* 2 Objective
* 3 Spacecraft
* 4 Telescope
* 5 Timeline
* 5.1 Development
* 5.2 Construction and testing
* 5.3 Launch and trajectory
* 6 See also
* 7 Notes
* 8 References
* 9 External links

## Background

The Ariel mission is being developed by a consortium of various institutions from eleven member states of the European Space Agency (ESA),[lower-alpha 1] and international contributors from four countries.[lower-alpha 2] The project is led by principal investigator Giovanna Tinetti of the University College London,[8][9] who had previously led the unsuccessful Exoplanet Characterisation Observatory (EcHO) proposal for the M3 Cosmic Vision launch slot.[10][11]; alongside RAL Space, STFC for the PLM engineering consortium leadership.

Operations of the mission and the spacecraft will be handled jointly by ESA and the consortium behind the mission's development, through a coordinated Instrument Operations and Science Data Centre (IOSDC).[7] A Mission Operations Centre (MOC) will be set up at the European Space Operations Centre (ESOC) in Darmstadt, Germany, while a concurrent Ariel Science Operations Centre (SOC) will be set up at the European Space Astronomy Centre (ESAC) near Madrid, Spain.[7] The MOC will be responsible for the spacecraft itself, while the SOC will be responsible for archiving mission data and scientific data downlinked from the spacecraft. The IOSDC will help develop results from the mission based on data received by the SOC.[7]

## Objective

Ariel will observe 1,000 planets orbiting distant stars and make the first large-scale survey of the chemistry of exoplanet atmospheres.[12] The objective is to answer fundamental questions about how planetary systems form and evolve.[12] A spectrometer will spread the light into a spectrum and determine the chemical fingerprints of gases in the planets' atmospheres.[12] This will enable scientists to understand how the chemistry of a planet links to the environment in which it forms, and how its formation and evolution are affected by its parent star.[12] Ariel will study a diverse population of exoplanets in a wide variety of environments, but it will focus on warm and hot planets in orbits close to their star.[12]

## Spacecraft

The design of the Ariel spacecraft is based on that intended for the Exoplanet Characterisation Observatory (EChO) mission, and has heritage from the thermal design of the Planck space observatory.[7][13] The body of the spacecraft is split into two distinct modules known as the Service Module (SVM) and the Payload Module (PLM). The PLM will complete its Assembly, Integration and Test (AIT) at RAL Space, STFC. The PLM consists of three aluminium V-Grooves and three pairs of low conductivity fibreglass bipod struts supporting the PLM.[13] A basic horizontal telescope configuration is used for the PLM itself, housing all of the spacecraft's scientific instruments and its oval 1.1 m × 0.7 m (3 ft 7 in × 2 ft 4 in) primary mirror.[13][1] At launch, the spacecraft will have a fuelled mass of 1,300 kg (2,900 lb), and will have a dry mass of 1,000 kg (2,200 lb).[1] The PLM will account for around 300 kg (660 lb) of that mass.[1]

## Telescope

The Ariel telescope's assembly is an off-axis Cassegrain telescope followed by a third parabolic mirror to recollimate the beam. The telescope uses an oval 1.1 m × 0.7 m (3 ft 7 in × 2 ft 4 in) primary mirror; the imaging quality of the system is limited by diffraction for wavelengths longer than about 3 μm, and its focal ratio (f) is 13.4.[14] The system will acquire images in the visible and near-infrared spectrum.[14] The near-infrared sensor and its front-end driver board is the same as that of Euclid's NISP instrument. To operate its infrared spectroscope between 1.95–7.8 μm, the telescope will be cooled to a temperature of 55 K (−218.2 °C; −360.7 °F).[7][14]

Ariel's 1.1-m-diameter primary mirror will be the largest telescope mirror ever constructed completely from aluminium.[15][16] It will be built in a conventional way from a single large piece of metal.[17] However, for future space telescopes, ESA is developing techniques for joining together multiple aluminium segments to form a single large mirror.[18]

## Timeline

### Development

In August 2017, NASA conditionally selected Contribution to ARIEL Spectroscopy of Exoplanets (CASE) as a Partner Mission of Opportunity, pending the result of ESA's Cosmic Vision selection.[19] Under the proposal NASA provides two fine guidance sensors for the Ariel spacecraft in return for the participation of U.S. scientists in the mission.[20] CASE was officially selected in November 2019, with JPL astrophysicist Mark Swain as principal investigator.[21]

In March 2018, ESA officially selected Ariel as its fourth medium-class science mission. At that time, its launch was planned for 2028.[22][23][24] In November 2020, Ariel moved from study to implementation phase, with a launch scheduled for 2029.[25] On 7 December 2021, ESA announced that the €200 million contract to build Ariel's SVM had been awarded to Airbus Defence and Space.[26] In August 2023, Ariel passed its payload Preliminary Design Review.[27] On 6 December 2023, ESA approved the construction of Ariel while maintaining a targeted launch date of 2029.[28]

### Construction and testing

In October 2024, the mission's construction phase has started at Airbus in Toulouse, France with the assembly of Ariel's structural model.[29]

### Launch and trajectory

The Ariel spacecraft is expected to be launched in 2031[3] by Arianespace's Ariane 62 launch vehicle.[26][25][30][31] It will be launched from the Guiana Space Centre in Kourou, French Guiana,[30][31] from ELA-4 purpose-built for Ariane 6 launches.[32] Ariel will be launched to the Sun-Earth Lagrange point L2, in a position located at a distance of 1,500,000 km (930,000 mi) from Earth,[30] where it will encounter a very stable thermal environment that is required for its operations.[31]

## See also

* List of European Space Agency programmes and missions
* List of space telescopes
* CHEOPS and PLATO – Cosmic Vision exoplanetology missions
* FINESSE – NASA's cancelled mission proposal similar to ARIEL

## Notes

1. ↑ These are the University of Vienna from Austria, the Universities of Leuven and Liège from Belgium, the Technical University of Denmark, the CEA, CNES, Paris Institute of Astrophysics, Marseille, Côte d'Azur, and Paris Observatories in France, the Max Planck Society and University of Hamburg in Germany, SRON and the Universities of Amsterdam, Delft, and Leiden in the Netherlands, the Space Research Centre of Polish Academy of Sciences, the CAB, Institute of Space Sciences and the Institute of Astrophysics of the Canary Islands in Spain, University of Bern in Switzerland, and the ATC and the Universities of Cardiff, Exeter, Hertfordshire, Keele, Leicester, London, and Oxford in the United Kingdom.[7]
2. ↑ These are the Université de Montréal and the University of Toronto in Canada, the ELSI, Tokyo Institute of Technology, and Osaka University in Japan, the National Autonomous University of Mexico, and Caltech, the Lunar and Planetary Laboratory (LPL) and Jet Propulsion Laboratory (JPL), Lunar and Planetary Institute, and Universities of Arizona State, Chicago, and Princeton in the United States.[7]

## References

1. ↑ 1.0 1.1 1.2 1.3 1.4 "Facts & Figures". ARIEL Space Mission. University College London. May 2017. https://ariel-spacemission.eu/ariel-media/.
2. ↑ "ARIEL Spacecraft". ESA. 11 November 2020. https://sci.esa.int/web/ariel/-/59800-spacecraft.
3. ↑ 3.0 3.1 3.2 "ESA's Comet Interceptor mission moves up launch". 2026-01-14. https://spacenews.com/esas-comet-interceptor-mission-moves-up-launch/.
4. ↑ "Ariel exoplanet survey mission greenlit by ESA". The Engineer. 13 November 2020. https://www.theengineer.co.uk/content/news/ariel-exoplanet-survey-mission-greenlit-by-esa.
5. ↑ Coates, Rebecca; Civiš, Svatopluk, eds. (3 August 2023). "Ariel passes major milestone". www.avcr.cz (Press release). Czech Academy of Sciences/University College London. Retrieved 7 November 2025.
6. ↑ Greaves, Mark, ed. (12 November 2020). "UCL-led space mission to uncover distant planets" (Press release). University College London. Archived from the original on 17 July 2025. Retrieved 7 November 2025.
7. ↑ 7.0 7.1 7.2 7.3 7.4 7.5 7.6 ARIEL – Atmospheric Remote-sensing Infrared Exoplanet Large-survey -- Enabling Planetary Science across Light-years (PDF) (Technical report). ESA. March 2017. (ESA/SCI(2017)2). Archived (PDF) from the original on 22 March 2018. Retrieved 12 June 2021.
8. ↑ J. Amos (2018-03-20). "Discovering the nature of planets". BBC News. https://www.bbc.com/news/av/science-environment-43477355/discovering-the-nature-of-planets.
9. ↑ E. Gibney (2018). "First space mission dedicated to exoplanet atmospheres gets green light". Nature 555 (7698): 571. doi:10.1038/d41586-018-03445-5. Bibcode: 2018Natur.555..571G.
10. ↑ V. Gewin (2011). "Turning point: Giovanna Tinetti". Nature 472 (7342): 251. doi:10.1038/nj7342-251a. ISSN 1476-4687.
11. ↑ "ESA selects planet-hunting PLATO mission" (Press release). Noordwijk, Netherlands: ESA. 21 February 2014. Archived from the original on 5 October 2025. Retrieved 22 March 2018 - via Astronomy.
12. ↑ 12.0 12.1 12.2 12.3 12.4 "Ariel exoplanet mission selected as ESA's next medium-class science mission" (PDF) (Press release). University College London/Science and Technology Facilities Council. 20 March 2018. Archived (PDF) from the original on 12 December 2025. Retrieved 12 June 2021.
13. ↑ 13.0 13.1 13.2 "ARIEL: Spacecraft". ESA. 20 March 2018. https://sci.esa.int/web/ariel/-/59800-spacecraft.
14. ↑ 14.0 14.1 14.2 "ARIEL - Payload". ESA. https://sci.esa.int/web/ariel/-/59801-payload.
15. ↑ E. Guerriero; P. Chioetto; A. Tozzi (August 2022). "Heat treatment procedure of the aluminium 6061-T651 for the Ariel telescope mirrors". Space Telescopes and Instrumentation - Optical, Infrared, and Millimeter Wave. 12180. Montréal, Canada. pp. 1218014. doi:10.1117/12.2628178. ISBN 978-1-5106-5341-2. Bibcode: 2022SPIE12180E..14G. https://discovery.ucl.ac.uk/id/eprint/10159730/.
16. ↑ P. Picchi; A. Tozzi; A. Brucalassi (June 2024). "Aluminum based large telescopes: The ARIEL mission case". Space Telescopes and Instrumentation 2024: Optical, Infrared, and Millimeter Wave. 13092. Yokohama, Japan. p. 284. doi:10.1117/12.3018855. ISBN 978-1-5106-7507-0. Bibcode: 2024SPIE13092E..4GP. https://www.spiedigitallibrary.org/conference-proceedings-of-spie/13092/3018855/Aluminum-based-large-telescopes-the-ARIEL-mission-case/10.1117/12.3018855.short.
17. ↑ V. Da Deppo; E. Pace; G. Morgante (September 2018). "The primary mirror of the ARIEL mission: study and development of a prototype". European Planetary Science Congress. 12. Berlin, Germany. Bibcode: 2018EPSC...12.1079D. https://meetingorganizer.copernicus.org/EPSC2018/EPSC2018-1079.pdf.
18. ↑ "To see the Universe in aluminium". European Space Agency. 2023-12-07. https://www.esa.int/Enabling_Support/Space_Engineering_Technology/To_see_the_Universe_in_aluminium.
19. ↑ Landau, Elizabeth; Chou, Felicia, eds. (10 August 2017). "NASA Selects Proposals to Study Galaxies, Stars, Planets" (Press release). NASA/JPL. 2017-213. Archived from the original on 16 January 2021. Retrieved 28 April 2018. This article incorporates text from this source, which is in the public domain.
20. ↑ "FINESSE and ARIEL + CASE: Dedicated Transit Spectroscopy Missions for the Post-TESS Era". Cosmic Origins Program Analysis Group (COPAG). NASA. https://cor.gsfc.nasa.gov/copag/AAS_Jan2018/bean_finesse_case.pdf. This article incorporates text from this source, which is in the public domain.
21. ↑ Landau, Elizabeth (8 November 2019). "NASA Instrument to Probe Planet Clouds on European Mission" (Press release). NASA/JPL. 2019-225. Archived from the original on 5 December 2021. Retrieved 12 November 2019. This article incorporates text from this source, which is in the public domain.
22. ↑ S. Clark. "Exoplanet telescope selected as ESA's next space science mission". Spaceflight Now. https://spaceflightnow.com/2018/03/22/exoplanet-telescope-selected-as-esas-next-space-science-mission/.
23. ↑ de Lapparent, Valérie (March 2018). "The ARIEL space mission selected by the European Space Agency". www.iap.fr (Press release). Institut d'Astrophysique de Paris. Archived from the original on 26 December 2025. Retrieved 7 November 2025.
24. ↑ "ESA's next science mission to focus on nature of exoplanets". European Space Agency. 2018-03-20. https://www.esa.int/Science_Exploration/Space_Science/ESA_s_next_science_mission_to_focus_on_nature_of_exoplanets.
25. ↑ 25.0 25.1 "Ariel moves from blueprint to reality". European Space Agency. 2020-11-12. https://www.esa.int/Science_Exploration/Space_Science/Ariel_moves_from_blueprint_to_reality.
26. ↑ 26.0 26.1 A. Parsonson (2021-12-07). "ESA award €200m contract to Airbus to build Ariel observatory". European Spaceflight. https://europeanspaceflight.com/esa-award-e200m-contract-to-airbus-to-build-ariel-observatory/.
27. ↑ "Exoplanet surveyor Ariel passes major milestone". European Space Agency. 2023-08-09. https://www.esa.int/Science_Exploration/Space_Science/Exoplanet_surveyor_Ariel_passes_major_milestone.
28. ↑ Gough, Evan (6 December 2023). "ESA's Ariel Mission is Approved to Begin Construction". Universe Today. https://www.universetoday.com/articles/esas-ariel-mission-is-approved-to-begin-construction.
29. ↑ "Ariel takes shape and first shake". European Space Agency. 2024-10-29. https://www.esa.int/ESA_Multimedia/Images/2024/10/Ariel_takes_shape_and_first_shake.
30. ↑ 30.0 30.1 30.2 "ESA's next science mission to focus on nature of exoplanets". ESA Science & Technology Portal. ESA. 20 March 2018. https://sci.esa.int/web/cosmic-vision/-/59796-esa-s-next-science-mission-to-focus-on-nature-of-exoplanets.
31. ↑ 31.0 31.1 31.2 Warren, Melissa (20 March 2018). "UK part of Ariel exoplanet project selected as ESA's next medium-class science mission". Science and Technology Facilities Council. https://www.ralspace.stfc.ac.uk/Pages/ARIEL-exoplanet-mission-selected-as-ESA’s-next-medium-class-science-mission.aspx.
32. ↑ "Race to build Ariane 6 rocket launch pad". Euronews. 14 December 2017. https://www.euronews.com/next/2017/12/14/race-to-build-ariane-6-rocket-launch-pad.

## External links

* ARIEL official website
* ARIEL at the European Space Agency

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* Mikhailo Lomonosov (since 2016)
* Mini-EUSO (since 2019)
* NCLE (since 2018)
* NEOSSat (since 2013)
* NICER (since 2017)
* NuSTAR (since 2012)
* Odin (since 2001)
* SDO (since 2010)
* SOHO (since 1995)
* SOLAR (since 2008)
* Spektr-RG (since 2019)
* Spitzer (since 2003)
* STEREO (since 2006)
* Swift (since 2004)
* TESS (since 2018)
* WISE (since 2009)
* XMM-Newton (since 1999)

Planned|

* CHEOPS (2019)
* iWF-MAXI (2019)
* Astro-1 Telescope (2020)
* ILO-1 (2020)
* LUCI (2020)
* Nano-JASMINE (2020)
* ORBIS (2020)
* Solar Orbiter (SolO) (2020)
* IXPE (2021)
* James Webb (JWST) (2021)
* LORD (2021)
* SVOM (2021)
* XPoSat (2021)
* Euclid (2022)
* Space Solar Telescope (2022)
* XRISM (2022)
* Xuntian (2022)
* K-EUSO (2023)
* Solar-C (2023)
* SPHEREx (2023)
* Small-JASMINE (2024)
* Near-Earth Object Surveillance Mission (2025+)
* Spektr-UV (2025)
* WFIRST (2025+)
* PLATO (2026)
* LiteBIRD (2027)
* ARIEL (2028)
* Spektr-M (2030+)
* ATHENA (2031)
* LISA (2034)

Proposed|

* Arcus
* AstroSat-2
* EXCEDE
* Fresnel Imager
* FOCAL
* HabEx
* Hibari
* Hypertelescope
* JEM-EUSO
* LUVOIR
* ATLAST
* HDST
* Lynx
* Nautilus Deep Space Observatory
* New Worlds Mission
* NRO donation to NASA
* OST
* PhoENiX
* Solar-D
* SPICA
* THEIA
* THESEUS

Retired|

* Akari (Astro-F) (2006–2011)
* ALEXIS (1993–2005)
* Alouette 1 (1962–1972)
* Ariel 1 (1962, 1964)
* Ariel 2 (1964)
* Ariel 3 (1967–1969)
* Ariel 4 (1971–1972)
* Ariel 5 (1974–1980)
* Ariel 6 (1979–1982)
* ATM (1973–1974)
* ASCA (Astro-D) (1993–2000)
* Astro-1 (1990)
* BBXRT
* HUT
* Astro-2 (HUT) (1995)
* Astron (1983–1989)
* ANS (1974–1976)
* BeppoSAX (1996–2003)
* CHIPSat (2003–2008)
* Compton (CGRO) (1991–2000)
* CoRoT (2006–2013)
* Cos-B (1975–1982)
* COBE (1989–1993)
* DXS (1993)
* EPOCh (2008)
* EPOXI (2010)
* Explorer 11 (1961)
* EXOSAT (1983–1986)
* EUVE (1992–2001)
* FUSE (1999–2007)
* Kvant-1 (1987–2001)
* GALEX (2003–2013)
* Gamma (1990–1992)
* Ginga (Astro-C) (1987–1991)
* Granat (1989–1998)
* Hakucho (CORSA-b) (1979–1985)
* HALCA (MUSES-B) (1997–2005)
* HEAO-1 (1977–1979)
* Herschel (2009–2013)
* Hinotori (Astro-A) (1981–1991)
* HEAO-2 (Einstein Obs.) (1978–1982)
* HEAO-3 (1979–1981)
* HETE-2 (2000–2008)
* Hipparcos (1989–1993)
* IUE (1978–1996)
* IRAS (1983)
* IRTS (1995–1996)
* ISO (1996–1998)
* IXAE (1996–2004)
* Kepler (2009–2018)
* Kristall (1990–2001)
* LEGRI (1997–2002)
* LISA Pathfinder (2015–2017)
* MOST (2003–2019)
* MSX (1996–1997)
* OAO-2 (1968–1973)
* OAO-3 (Copernicus) (1972–1981)
* Orbiting Solar Observatory
* OSO 1
* OSO 2/OSO B
* OSO 3
* OSO 4
* OSO 5
* OSO 6
* OSO 7
* OSO 8
* Orion 1 (1971)
* Orion 2 (1973)
* PAMELA (2006–2016)
* PicSat (2018)
* Planck (2009–2013)
* RELIKT-1 (1983–1984)
* R/HESSI (2002–2018)
* ROSAT (1990–1999)
* RXTE (1995–2012)
* SAMPEX (1992–2004)
* SAS-B (1972–1973)
* SAS-C (1975–1979)
* Solwind (1979–1985)
* Spektr-R (2011–2019)
* Suzaku (Astro-EII) (2005–2015)
* Taiyo (SRATS) (1975–1980)
* Tenma (Astro-B) (1983–1985)
* Uhuru (1970–1973)
* Vanguard 3 (1959)
* WMAP (2001–2010)
* Yokoh (Solar-A) (1991–2001)

Hibernating
(Mission completed)|

* SWAS (1998–2005)
* TRACE (1998–2010)

Lost|

* OAO-1 (1966)
* OAO-B (1970)
* CORSA (1976)
* OSO C (1965)
* ABRIXAS (1999)
* HETE-1 (1996)
* WIRE (1999)
* Astro-E (2000)
* Tsubame (2014–2015)
* Hitomi (Astro-H) (2016)

Cancelled|

* AOSO
* Astro-G
* Constellation-X
* Darwin
* Destiny
* EChO
* Eddington
* FAME
* FINESSE
* GEMS
* HOP
* IXO
* JDEM
* LOFT
* OSO J
* OSO K
* Sentinel
* SIM & SIMlite
* SNAP
* SPOrt
* TAUVEX
* TPF
* XEUS
* XIPE

See also|

* Great Observatories program
* List of space telescopes
* List of proposed space observatories
* List of X-ray space telescopes

* Category

* v
* t
* e

Future spaceflights

Crewed|

| 2020|

* Soyuz MS-16 (April)
* Soyuz MS-17 (October)
* Shenzhou 12
* Crew Dragon Demo-2
* Boeing Crewed Flight Test
* USCV-1
* USCV-2
* New Shepard (crewed flight test)
* VSS Unity VF02

|

2021|

* Gaganyaan Crewed Flight 1
* Shenzhou 13
* USCV-3

2022|

* Artemis 2

2023+|

* #dearMoon project (2023)
* Artemis 3 (2024)

Robotic|

| 2020|

* AFSPC-7
* ALOS-3
* ALOS-4
* Artemis 1 (November)
* Orion
* Lunar Flashlight
* NEA Scout
* BioSentinel
* SkyFire
* Lunar IceCube
* CuSP
* LunaH-Map
* EQUULEUS
* OMOTENASHI
* ArgoMoon
* Cislunar Explorers
* CU-E3
* Team Miles
* Chandrayaan-3
* Chang'e 5
* GSAT-20
* Hope Mars Mission (July)
* HX-1 (July–August)
* Ingenio
* Inmarsat-6 F1
* JCSAT-17
* Kounotori 9 (May)
* Mars 2020 (July–August)
* MX-1E (July)
* Nauka / European Robotic Arm (December)
* QZS-1R
* RAPIS-2 / Z-Sat / DRUMS / KOSEN-1
* Rosalind Franklin rover and Kazachok lander (July)
* Solar Orbiter (February)
* Space Complex Alpha
* TARANIS

|

2021|

* Aditya-L1
* Astrobotic M1 (June)
* AEM rovers
* Uni
* EXA/AEC lunar orbiter
* B330
* CAPSTONE (December)
* DART / LICIA (June)
* Dream Chaser (September)
* Hakuto-R M1 (October)
* IXPE (April)
* James Webb Space Telescope (March)
* Landsat 9 (January)
* Lucy (October)
* Luna 25 (July)
* Nova-C (July)
* PROBA-3 (Q2)
* PTScientists
* Tianhe
* SES-17
* Space RIDER
* UN/Dream Chaser
* Wentian
* XPoSat

2022|

* Biomass (October)
* DESTINY+
* EarthCARE (June)
* Euclid (June)
* HTV-X1
* JUICE (June)
* KPLO (July)
* MetOp-SG Series A
* NISAR (September)
* Power and Propulsion Element (December)
* Prichal
* Psyche (August)
* PUNCH / TRACERS
* Soyuz GVK-1
* SpaceX Starship (1st Mars departure)
* TEREX-1
* Weather System Follow-on Microwave
* XRISM / SLIM (January)

2023|

* Chang'e 7
* Hakuto-R M2 (March)
* MetOp-SG Series B
* QZS-5
* QZS-6
* QZS-7
* Shukrayaan-1
* SMILE
* SPHEREx

2024+|

* Chang'e 6 (2023 or 2024)
* FLEX
* GOES-U (2024)
* Hera / APEX / Juventas (October 2024)
* IMAP / SWFO-L1 (October 2024)
* Luna 26 (2024)
* MMX (September 2024)
* MOM 2 (2024)
* Small-JASMINE (2024)
* ZhengHe (2024)
* Europa Clipper (2025)
* Luna 27 (2025)
* Luna 28 (2025+)
* Spektr-UV (2025)
* Dragonfly (2026)
* PLATO (2026)
* Venera-D (2026 or 2031)
* Chang'e 8 (2027)
* LiteBIRD (2027)
* ARIEL / Comet Interceptor]] (2028)
* ATHENA (2031)
* LISA (2034)

TBA|

* Energia-100
* Europa Lander (2025?)
* KiwiSAT
* Lybid 1
* Nano-JASMINE
* Near-Earth Object Surveillance Mission
* WFIRST (mid-2020s)

Recently
launched|

* Progress MS-13 (6 December)
* Jilin-1 Gaofen-02B (7 December)
* HEAD-2A / 2B (7 December)
* GLONASS-M List of GLONASS satellites

* List of proposed missions to the Moon
* List of proposed space observatories

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Original source: https://en.wikipedia.org/wiki/ARIEL. Read more

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