Jupiter Icy Moons Explorer
JUICE spacecraft.png
Artist's impression of the JUICE spacecraft
Mission typePlanetary science
Mission durationCruise phase: 8 years
Science phase: 3.5 years
Spacecraft properties
ManufacturerAirbus Defence and Space
Launch mass6,042.9 kg (13,322 lb)
Dry mass2,405 kg (5,302 lb)
Power820 watts[1] from a solar panel ~100 m2 (1,100 sq ft)[2]
Start of mission
Launch date13 April 2023 (planned)[3]
RocketAriane 5 ECA
Launch siteCentre Spatial Guyanais, ELA-3
Flyby of Moon
Closest approachAugust 2024
Flyby of Earth
Closest approachAugust 2024
Flyby of Venus
Closest approach31 August 2025
Flyby of Earth
Closest approach29 September 2026
Flyby of Earth
Closest approach18 January 2029
Flyby of 223 Rosa
Closest approach15 October 2029 (proposed)
Jupiter orbiter
Orbital insertionJuly 2031 (planned)
Orbital departureDecember 2034
Ganymede orbiter
Orbital insertionDecember 2034 (planned)
Orbital parameters
Periapsis altitude500 km (310 mi)
Apoapsis altitude500 km (310 mi)
JUICE mission logo

JUICE mission insignia
← Euclid

The Jupiter Icy Moons Explorer (JUICE) is an interplanetary spacecraft in development by the European Space Agency (ESA) with Airbus Defence and Space as the main contractor. The mission will study three of Jupiter's Galilean moons: Ganymede, Callisto, and Europa (excluding the volcanically active Io; Io is not an icy moon) all of which are thought to have significant bodies of liquid water beneath their surfaces, making them potentially habitable environments.[4]

The spacecraft is scheduled to launch on 13 April 2023 and will reach Jupiter in July 2031 after four gravity assists and eight years of travel.[5][6] In December 2034, the spacecraft will enter orbit around Ganymede for its close up science mission,[5] becoming the first spacecraft to orbit a moon other than the Moon of Earth. The selection of this mission for the L1 launch slot of ESA's Cosmic Vision science programme was announced on 2 May 2012.[7][8] Its period of operations will overlap with NASA's Europa Clipper mission, launching in 2024.


A concept art for the Jupiter Ganymede Orbiter, the ESA component of the proposed Europa Jupiter System Mission – Laplace
A concept art for the Jupiter Ganymede Orbiter, the ESA component of the proposed Europa Jupiter System Mission – Laplace

The mission started as a reformulation of the Jupiter Ganymede Orbiter proposal, which was to be ESA's component of the cancelled Europa Jupiter System Mission – Laplace (EJSM-Laplace).[9] It became a candidate for the first L-class mission (L1) of the ESA Cosmic Vision Programme, and its selection was announced on 2 May 2012.[7]

In April 2012, JUICE was recommended over the proposed Advanced Telescope for High Energy Astrophysics (ATHENA) X-ray telescope and a gravitational wave observatory (New Gravitational wave Observatory (NGO)).[10][11]

In July 2015, Airbus Defence and Space was selected as the prime contractor to design and build the probe, to be assembled in Toulouse, France.[12]

This section needs expansion. You can help by adding to it. (April 2022)


Launch and trajectory

JUICE will be launched on 13 April 2023 on an Ariane 5 launch vehicle from the Guiana Space Centre.[3] Following the launch, there will be multiple planned gravity assists to put JUICE on a trajectory to Jupiter: a flyby of the Earth–Moon system in August 2024, Venus in August 2025, second flyby of Earth in September 2026, and a final third flyby of Earth in January 2029.[5]

JUICE will pass through the asteroid belt twice. A flyby of the asteroid 223 Rosa has been proposed, and would occur in October 2029.[13]

Arrival at the Jovian system

When it arrives in Jupiter's system in July 2031, JUICE will first perform a flyby of Ganymede in preparation for Jupiter orbital insertion ≈ 7.5 hours later. The first orbit will be elongated, with subsequent orbits gradually lowered over time, resulting in a circular orbit around Jupiter.[5]

The first Europa flyby will take place in July 2032. JUICE will enter a high inclination orbit to allow exploration of Jupiter's polar regions and to study Jupiter's magnetosphere.[5]

Orbital insertion on Ganymede

In December 2034, JUICE will enter an elliptical orbit around Ganymede, becoming the first spacecraft to orbit a moon other than Earth's Moon. The first orbit will be at a distance of 5,000 km (3,100 mi). In 2035, JUICE will enter a circular orbit 500 km (310 mi) above the surface of Ganymede.[5] JUICE will study Ganymede's composition and magnetosphere among other things.

Planned deorbit on Ganymede

When the spacecraft consumes its remaining propellant, JUICE is planned to be deorbited and impact Ganymede at the end of 2035.[5]

Trajectories of JUICE
Around the Sun
Around Jupiter
Around Ganymede
  Sun ·   Earth ·   JUICE ·   Venus ·   223 Rosa ·   Jupiter ·   Ganymede ·   Callisto  ·   Europa

Science objectives

Ganymede view by Galileo
Ganymede view by Galileo
Section of Europa's icy surface
Section of Europa's icy surface

The JUICE orbiter will perform detailed investigations on Ganymede and evaluate its potential to support life. Investigations of Europa and Callisto will complete a comparative picture of these Galilean moons.[14] The three moons are thought to harbour internal liquid water oceans, and so are central to understanding the habitability of icy worlds.

The main science objectives for Ganymede, and to a lesser extent for Callisto, are:[14]

For Europa, the focus is on the chemistry essential to life, including organic molecules, and on understanding the formation of surface features and the composition of the non-water-ice material. Furthermore, JUICE will provide the first subsurface sounding of the moon, including the first determination of the minimal thickness of the icy crust over the most recently active regions.

More distant spatially resolved observations will also be carried out for several minor irregular satellites and the volcanically active moon Io.


Design drivers

The main spacecraft design drivers are related to the large distance to the Sun, the use of solar power, and Jupiter's harsh radiation environment. The orbit insertions at Jupiter and Ganymede and the large number of flyby manoeuvres (more than 25 gravity assists, and two Europa flybys) requires the spacecraft to carry about 3,000 kg (6,600 lb) of chemical propellant.[15]

Gravity assists include:[16]

Science instruments

JUICE scheme
JUICE scheme

On 21 February 2013, after a competition, 11 science instruments were selected by ESA, which are being developed by science and engineering teams from all over Europe, with participation from the US.[17][18][19][20]
Japan will also contribute several components for SWI, RPWI, GALA, PEP, JANUS and J-MAG instruments, and will facilitate testing.[21][22][23]

Jovis, Amorum ac Natorum Undique Scrutator (JANUS)

The name is Latin for "comprehensive observation of Jupiter, his love affairs and descendants."[24] A camera system to image Ganymede and interesting parts of the surface of Callisto at better than 400 m/pixel (resolution limited by mission data volume). Selected targets will be investigated in high-resolution with a spatial resolution from 25 m/pixel down to 2.4 m/pixel with a 1.3° field of view. The camera system has 13 panchromatic, broad and narrow-band filters in the 0.36 µm to 1.1 µm range, and provides stereo imaging capabilities. JANUS will also allow relating spectral, laser and radar measurements to geomorphology and thus will provide the overall geological context.

Moons and Jupiter Imaging Spectrometer (MAJIS)

A visible and infrared imaging spectrograph operating from 400 nm to 5.70 µm, with spectral resolution of 3–7 nm, that will observe tropospheric cloud features and minor gas species on Jupiter and will investigate the composition of ices and minerals on the surfaces of the icy moons. The spatial resolution will be down to 75 m (246 ft) on Ganymede and about 100 km (62 mi) on Jupiter.

UV Imaging Spectrograph (UVS)

An imaging spectrograph operating in the wavelength range 55–210 nm with spectral resolution of <0.6 nm that will characterise exospheres and aurorae of the icy moons, including plume searches on Europa, and study the Jovian upper atmosphere and aurorae. Resolution up to 500 m (1,600 ft) observing Ganymede and up to 250 km (160 mi) observing Jupiter.

Sub-millimeter Wave Instrument (SWI)

A spectrometer using a 30 cm (12 in) antenna and working in 1080–1275 GHz and 530–601 GHz with spectral resolving power of ~107 that will study Jupiter's stratosphere and troposphere, and the exospheres and surfaces of the icy moons.

Ganymede Laser Altimeter (GALA)

A laser altimeter with a 20 m (66 ft) spot size and 10 cm (3.9 in) vertical resolution at 200 km (120 mi) intended for studying topography of icy moons and tidal deformations of Ganymede.

Radar for Icy Moons Exploration (RIME)

An ice-penetrating radar working at frequency of 9 MHz (1 and 3 MHz bandwidth) emitted by a 16 m (52 ft) antenna; will be used to study the subsurface structure of Jovian moons down to 9 km (5.6 mi) depth with vertical resolution up to 30 m (98 ft) in ice.

JUICE-Magnetometer (J-MAG)

The scalar sub-instrument (MAGSCA) is an optical magnetometer with low absolute error, that is part of J-MAG
The scalar sub-instrument (MAGSCA) is an optical magnetometer with low absolute error, that is part of J-MAG

Will study the subsurface oceans of the icy moons and the interaction of Jovian magnetic field with the magnetic field of Ganymede using a sensitive magnetometer.

Particle Environment Package (PEP)

A suite of six sensors to study the magnetosphere of Jupiter and its interactions with the Jovian moons. PEP will measure positive and negative ions, electrons, exospheric neutral gas, thermal plasma and energetic neutral atoms present in all domains of the Jupiter system from 1 meV to 1 MeV energy.

Radio and Plasma Wave Investigation (RPWI)

Will characterise the plasma environment and radio emissions around the spacecraft, it is composed of four experiments: GANDALF, MIME, FRODO and JENRAGE. RPWI will use four Langmuir probes, each one mounted at the end of its own dedicated boom, and sensitive up to 1.6 MHz to characterize plasma and receivers in the frequency range 80 kHz to 45 MHz to measure radio emissions. This scientific instrument is somewhat notable for using Sonic as part of its logo.[25][26]

Gravity and Geophysics of Jupiter and Galilean Moons (3GM)

3GM is a radio science package comprising a Ka transponder and an ultrastable oscillator.[27] 3GM will be used to study the gravity field – up to degree 10 – at Ganymede and the extent of internal oceans on the icy moons, and to investigate the structure of the neutral atmospheres and ionospheres of Jupiter (0.1 – 800 mbar) and its moons.

Planetary Radio Interferometer and Doppler Experiment (PRIDE)

The experiment will generate specific signals transmitted by JUICE's antenna and received by very-long-baseline interferometry to perform precision measurements of the gravity fields of Jupiter and its icy moons.


The craft will encounter two planets and the Moon before arriving at Jupiter.[5]

See also


  1. ^ Pultarova, Tereza (24 March 2017). "Europe's Jupiter explorer mission moves to prototype production". SpaceNews. Retrieved 25 March 2017.
  2. ^ Amos, Jonathan (9 December 2015). "Juice mission: Deal signed to build Jupiter probe". BBC News.
  3. ^ a b "Juice on final stretch for launch to Jupiter". ESA. 10 February 2023. Retrieved 14 February 2023.
  4. ^ "ESA—Selection of the L1 mission" (PDF). 17 April 2012.
  5. ^ a b c d e f g h "Juice's journey and Jupiter system tour". ESA. 29 March 2022. Retrieved 3 April 2022.
  6. ^ "JUpiter ICy moons Explorer (JUICE)". NSSDC. NASA. 28 October 2021. Retrieved 10 November 2021.
  7. ^ a b "ESA selects 1bn-euro Juice probe to Jupiter". Jonathan Amos. BBC News. 2 May 2012.
  8. ^ Howell, Elizabeth (13 February 2017). "JUICE: Exploring Jupiter's Moons". Space.com. Retrieved 18 May 2020.
  9. ^ JUICE (JUpiter ICy moons Explorer): a European-led mission to the Jupiter system
  10. ^ Lakdawalla, Emily (18 April 2012). "JUICE: Europe's next mission to Jupiter?". The Planetary Society.
  11. ^ Amos, Jonathan (19 April 2012). "Disappointed astronomers battle on". BBC News.
  12. ^ "Preparing to build ESA's Jupiter mission". European Space Agency. 17 July 2015.
  13. ^ Avdellidou, C.; Pajola, M.; Lucchetti, A.; Agostini, L.; Delbo, M.; Mazzotta Epifani, E.; Bourdelle De Micas, J.; Devogèle, M.; Fornasier, S.; Van Belle, G.; Bruot, N.; Dotto, E.; Ieva, S.; Cremonese, G.; Palumbo, P. (2021). "Characterisation of the main belt asteroid (223) Rosa". Astronomy & Astrophysics. 656: L18. Bibcode:2021A&A...656L..18A. doi:10.1051/0004-6361/202142600. S2CID 244753425.
  14. ^ a b "JUICE—Science objectives". European Space Agency. 16 March 2012. Retrieved 20 April 2012.
  15. ^ "JUICE—Spacecraft". European Space Agency. 16 March 2012. Retrieved 20 April 2012.
  16. ^ "JUICE (JUpiter ICy moons Explorer)" (PDF). European Space Agency. March 2012. Retrieved 18 July 2013.
  17. ^ "ESA chooses instruments for its Jupiter Icy Moon Explorer". CSW. ESA. 21 February 2013. Retrieved 17 June 2013.
  18. ^ "JUICE science payload". European Space Agency. 7 March 2013. Retrieved 24 March 2014.
  19. ^ "The JUICE Instruments". CNES. 11 November 2013. Retrieved 24 March 2014.
  20. ^ "Jupiter Icy Moons Explorer (JUICE): Science objectives, mission and instruments" (PDF). 45th Lunar and Planetary Science Conference (2014). Retrieved 24 March 2014.
  21. ^ "JAXA – What is JUICE? – A "Great Journey to the Outer Solar System"".
  22. ^ Current Status of Japanese Participation to Jupiter Icy Moons Explorer "JUICE" Saito, Y.; Sasaki, S.; Kimura, J.; Tohara, K.; Fujimoto, M.; Sekine, Y. AGU; Fall Meeting Abstracts. Published in December 2015. Bibcode: 2015AGUFM.P11B2074S
  23. ^ [1] and [2] – Japan's contributions to JUICE instruments (in Japanese)
  24. ^ Köhler, Ulrich (December 2021). "Of Distant Moons and Oceans" (PDF). DLRmagazine. pp. 34–37.
  25. ^ "木星氷衛星探査機に搭載の電波観測装置が「ソニック・ザ・ヘッジホッグ」と共に木星へ|お知らせ|東北大学大学院理学研究科・理学部". www.sci.tohoku.ac.jp. Retrieved 21 January 2023.
  26. ^ "Actual Space Mission Picks Sonic The Hedgehog As An Official Mascot". Kotaku. 3 October 2019. Retrieved 21 January 2023.
  27. ^ Shapira, Aviv; Stern, Avinoam; Prazot, Shemi; Mann, Rony; Barash, Yefim; Detoma, Edoardo; Levy, Benny (2016). "An Ultra Stable Oscillator for the 3GM experiment of the JUICE mission". 2016 European Frequency and Time Forum (EFTF). pp. 1–5. doi:10.1109/EFTF.2016.7477766. ISBN 978-1-5090-0720-2. S2CID 2489857.