Minimize JUICE

JUICE (Jupiter Icy Moons Explorer)

Spacecraft     Development Status     Launch     Sensor Complement    References

JUICE is the first large-class mission in ESA's Cosmic Vision 2015-2025 program. Planned for launch in 2022 and arrival at Jupiter in 2029, it will spend at least three years making detailed observations of the giant gaseous planet Jupiter and three of its largest moons, Ganymede, Callisto and Europa. 1)

Science objectives: The focus of JUICE is to characterize the conditions that may have led to the emergence of habitable environments among the Jovian icy satellites, with special emphasis on the three ocean-bearing worlds, Ganymede, Europa, and Callisto. Ganymede is identified for detailed investigation since it provides a natural laboratory for analysis of the nature, evolution and potential habitability of icy worlds in general, but also because of the role it plays within the system of Galilean satellites, and its unique magnetic and plasma interactions with the surrounding Jovian environment. JUICE will determine the characteristics of liquid-water oceans below the icy surfaces of the moons. This will lead to an understanding of the possible sources and cycling of chemical and thermal energy, allow an investigation of the evolution and chemical composition of the surfaces and of the subsurface oceans, and enable an evaluation of the processes that have affected the satellites and their environments through time. The study of the diversity of the satellite system will be enhanced with additional information gathered remotely on Io and the smaller moons. The mission will also characterize the diversity of processes in the Jupiter system that may be required in order to provide a stable environment at the icy moons on geologic time scales, including gravitational coupling between the Galilean satellites and their long term tidal influence on the system as a whole. JUICE will carry out extensive new studies of Jupiter’s atmosphere, magnetosphere and their interaction with the satellites to further enhance our understanding of the evolution and dynamics of the Jovian system. 2) 3)

Some background:

In 2012, ESA selected the JUICE mission over two other candidates: NGO (New Gravitational wave Observatory), to hunt for gravitational waves, and ATHENA (Advanced Telescope for High-Energy Astrophysics). 4)

Jupiter’s diverse Galilean moons – volcanic Io, icy Europa and rock-ice Ganymede and Callisto – make the jovian system a miniature Solar System in its own right. With Europa, Ganymede and Callisto all thought to host internal oceans, the mission will study the moons as potential habitats for life, addressing two key themes of Cosmic Vision: what are the conditions for planet formation and the emergence of life, and how does the Solar System work? JUICE will continuously observe Jupiter’s atmosphere and magnetosphere, and the interaction of the Galilean moons with the gas giant planet.

JUICE will visit Callisto, the most heavily cratered object in the Solar System, and will twice fly by Europa. JUICE will make the first measurements of the thickness of Europa’s icy crust and will identify candidate sites for future in situ exploration.

The spacecraft will finally enter orbit around Ganymede in 2032, where it will study the icy surface and internal structure of the moon, including its subsurface ocean. Ganymede is the only moon in the Solar System known to generate its own magnetic field, and JUICE will observe the unique magnetic and plasma interactions with Jupiter’s magnetosphere in detail.

Today’s announcement is the culmination of a process started in 2004 when ESA consulted the wider scientific community to set Europe’s goals for space exploration in the coming decade.


Airbus is developing and building JUICE (JUpiter ICy moons Explorer) spacecraft for the European Space Agency, which will study Jupiter and its icy moons. As prime contractor, Airbus will employ 150 people and lead a consortium of more than 60 companies during the course of the project. 5)


Figure 1: Artist's impression of JUICE (image credit: Spacecraft: ESA/ATG medialab; Jupiter: NASA/ESA/J. Nichols; Ganymede: NASA/JPL; Io: NASA/JPL/University of Arizona; Callisto and Europa: NASA/JPL/DLR) 6)

PVA (Photovoltaic Assembly) for JUICE: The PVA design, development and verification (DD&V) foresee a thorough development, design verification and qualification activities along with associated test samples. 7)

The development of the JUICE PVA is progressing. A number of issues have been identified and recovery / alternative plans put in place to identify solutions. A robust baseline design is under final consolidation and will be available by the third quarter of 2018 allowing the release of all qualification campaigns.

Development status:

• August 28, 2019: This test facility at CERN, the European Organization for Nuclear Research, was used to simulate the high-radiation environment surrounding Jupiter to prepare for ESA’s JUICE mission to the largest planet in our Solar System. 8)

- All candidate hardware to be flown in space first needs to be tested against radiation: space is riddled with charged particles from the Sun and further out in the cosmos. An agreement with CERN gives access to the most intense beam radiation beams available – short of travelling into orbit.

- Initial testing of candidate components for ESA’s JUpiter ICy moons Explorer, JUICE, took place last year using CERN’s VESPER (Very energetic Electron facility for Space Planetary Exploration missions in harsh Radiative environments) facility.

- VESPER’s high energy electron beamline simulated conditions within Jupiter’s massive magnetic field, which has a million times greater volume than Earth’s own magnetosphere, trapping highly energetic charged particles within it to form intense radiation belts.

- Due to launch in 2022, JUICE needs to endure this harsh radiation environment in order to explore Callisto, Europa and Ganymede – moons of Jupiter theorized to hide liquid water oceans beneath their icy surfaces. JUICE is being built by Airbus for ESA, with construction of its spacecraft flight model due to begin next month.

- Last month ESA and CERN signed a new implementing protocol, building upon their existing cooperation ties.

- Signed by Franco Ongaro, ESA’s Director of Technology, Engineering and Quality, and Eckhard Elsen, CERN Director for Research and Computing, this new agreement identifies seven specific high-priority projects: high-energy electron tests; high-penetration heavy-ion tests; assessment of commercial off-the-shelf components and modules; in-orbit technology demonstration; ‘radiation-hard’ and ‘radiation-tolerant’ components and modules; radiation detectors monitors; and dosimeters and simulation tools for radiation effects.

- “The radiation environment that CERN is working with within its tunnels and experimental areas is very close to what we have in space,” explains Véronique Ferlet-Cavrois, Head of ESA’s Power Systems, EMC & Space Environment Division.

- “The underlying physics of the interaction between particles and components is the same, so it makes sense to share knowledge of components, design rules and simulation tools. Plus access to CERN facilities allows us to simulate the kind of high-energy electrons and cosmic rays found in space. At the same time we are collaborating on flying CERN-developed components for testing in space.”

- Petteri Nieminen, heading ESA’s Space Environments and Effects section adds: “Along with JUICE, CERN heavy-energy radiation testing will also be useful for our proposed Ice Giants mission to Neptune and Uranus. The spacecraft may have to be pass through Jupiter’s vast magnetic field on the way to these outer planets, and both worlds have radiation belts of their own.

- “And the ability to simulate cosmic rays benefits a huge number of missions, especially those venturing beyond Earth orbit, including Athena and LISA as well as JUICE. It is also a huge interest for human spaceflight and exploration to study radiobiology effects of heavy ion cosmic rays on astronaut DNA. Not to mention that radiation simulations developed in collaboration with CERN help set space environment specifications for all ESA missions.”


Figure 2: Technology image of the week: this CERN test facility was used to recreate the highly radioactive environment surrounding Jupiter for ESA’s JUICE mission (image credit: CERN)

• August 22, 2019: As part of preparations for the launch of ESA’s Jupiter Icy Moons Explorer, its navigation camera has been given a unique test: imaging its destination from Earth. 9)


Figure 3: Annotated image of Jupiter system captured in Juice NavCam test from Earth (image credit: Airbus DS)

- The NavCam has been specifically designed to be resistant to the harsh radiations environment around Jupiter and to acquire images of the planet, moon and background stars. Importantly, NavCam measurements will allow the spacecraft to be in the optimal trajectory and to consume as little fuel as possible during the grand tour of Jupiter, and to improve the pointing accuracy during these fast and close rendezvous approaches. The close encounters will bring the spacecraft between about 200 and 400 km to the moons.

- In June, a team of engineers took to the roof of the Airbus Defence and Space site in Toulouse to test the NavCam engineering model in real sky conditions. The purpose was to validate hardware and software interfaces, and to prepare the image processing and onboard navigation software that will be used in-flight to acquire images.

- In addition to observing Earth’s Moon and other objects, the instrument was pointed towards an obvious target in the night sky: Jupiter. The camera used the ‘Imaging mode’ and ‘Stars Centroiding Mode’ to test parameter settings which in turn will be used to fine-tune the image processing software at attitude control and navigation levels.

- “Unsurprisingly, some 640 million km away, the moons of Jupiter are seen only as a mere pixel or two, and Jupiter itself appears saturated in the long exposure images needed to capture both the moons and background stars, but these images are useful to fine-tune our image processing software that will run autonomously onboard the spacecraft,” says Gregory Jonniaux, Vision-Based Navigation expert at Airbus Defence and Space. “It felt particularly meaningful to conduct our tests already on our destination!”

- During the flybys themselves it will be possible to see surface features on these very different moons. In a separate test, the NavCam was optically fed with simulated views of the moons to process more realistic images of what can be expected once in the Jupiter system.


Figure 4: Simulated NavCam views of the Jupiter moons. Impressions of how the Jupiter Icy Moons Explorer will see moons Europa (left), Ganymede (middle) and Callisto (right) with its Navigation Camera (NavCam). To generate these images, the NavCam was fed simulated views – based on existing images of the moons – to process realistic views of what can be expected once in the Jupiter system (image credit: Airbus DS)

- Meanwhile the test navigation camera will be further improved with a full flight representative performance optics assembly by the end of the year, and will subsequently be used to support onboard software tests of the complete Juice spacecraft. After launch, the test camera will be used at ESA’s operations center to support the mission operations throughout its mission.

• June 17, 2019: Juice, will ride into space on an Ariane launch vehicle, Arianespace and ESA confirmed today at the International Paris Air Show. 10)

- Juice is the first large-class mission in ESA's Cosmic Vision 2015–2025 program. Its mission is devoted to complete a unique tour of the Jupiter system.

- Juice will spend at least three years making detailed observations of the giant gaseous planet Jupiter and in-depth studies of three of its largest moons and potentially ocean-bearing satellites, Ganymede, Europa and Callisto.

- The launch period for Juice will start in mid-2022 aboard an Ariane 5 or an Ariane 64 launch vehicle – depending on the final launch slot from from Europe’s Spaceport in French Guiana, South America.

• April 3, 2019: ESA's JUpiter ICy moons Explorer, JUICE, has been given the green light for full development after its critical design review was successfully concluded on 4 March. This major milestone marks the beginning of the qualification and production phase, taking this flagship mission one key step closer to starting its long journey to Jupiter in 2022. 11)

• March 20, 2019: A test version of the 10.5 m long magnetometer boom built for ESA’s mission to Jupiter, developed by SENER in Spain, seen being tested at ESA’s Test Center in the Netherlands, its mass borne by balloons. 12)

- The flight model will be mounted on the JUICE (Jupiter Icy Moons Explorer) spacecraft, due to launch in 2022, arriving at Jupiter in 2029. The mission will spend at least three years making detailed observations of the giant gaseous planet Jupiter and three of its largest moons: Ganymede, Callisto and Europa.

- The Juice spacecraft will carry the most powerful remote sensing, geophysical, and in situ payload complement ever flown to the outer Solar System. Its payload consists of 10 state-of-the-art instruments.

- This includes a magnetometer instrument that the boom will project clear of the main body of the spacecraft, allowing it to make measurements clear of any magnetic interference. Its goal is to measure Jupiter’s magnetic field, its interaction with the internal magnetic field of Ganymede, and to study subsurface oceans of the icy moons.

- The deployment of this qualification model boom has been performed before and after simulated launch vibration on the Test Center shaker tables to ensure it will deploy correctly in space. Since the boom will deploy in weightlessness, three helium balloons were used to help bear its weight in terrestrial gravity.


Figure 5: A test version of the 10.5 m long magnetometer boom built for ESA’s mission to Jupiter, developed by SENER in Spain, seen being tested at ESA’s Test Center in the Netherlands, its weight borne by balloons (image credit: ESA–G. Porter, CC BY-SA 3.0 IGO)

• December 11, 2018: The JUICE engineering model spacecraft test readiness review was completed successfully on 2 October, and the first engineering model instruments are now being delivered and tested. 13)


Figure 6: The engineering model of ESA's JUICE at the facilities of prime contractor Airbus Defence and Space in Toulouse, France. The central cylinder of the spacecraft is well visible in this view, along with the electrical harness (image credit: Airbus DS)

- A major step in the development of ESA's upcoming JUICE mission to the Jupiter system is the start of integration and testing of the spacecraft engineering model at the facilities of prime contractor Airbus Defence and Space in Toulouse, France.

- Following the JUICE flight model spacecraft test readiness review, in October 2019, the engineering model will be used to test procedures and study functional issues that may arise during the development testing of the flight model. The engineering model will also be used, on ground, in support of the actual spacecraft operations after launch.

• November 12, 2018: JUICE is ESA's future mission to explore the most massive planet in Solar System and its large moons Ganymede, Europa and Callisto. Planned for launch in June 2022, it will embark on a seven-year cruise that will make use of several flybys – of Earth, Venus, Earth, Mars, and Earth again – before leaving the inner Solar System en route to Jupiter. 14)

- All three moons are thought to have oceans of liquid water beneath their icy crusts, and the Radar for Icy Moons Exploration (RIME) instrument on Juice will be used to probe their subsurface structure. Emitted by a 16-m long antenna, the radar signals will penetrate the icy surfaces of Jupiter’s moons down to a depth of 9 km.

- RIME will be the first instrument of its kind capable of performing direct subsurface measurements of worlds in the outer Solar System, and it should provide key clues on the potential for such bodies to harbor habitable environments.

- Once in space, the instrument’s performance will be influenced by several factors, including the radiation pattern of the antenna. To evaluate these effects, a series of tests were carried out at ESA’s Hertz facility in September, using a 1:18 scale model of the RIME antenna – shrunk to a length of about 80 cm and mounted on a simplified, scaled-down model of the spacecraft.


Figure 7: A miniaturized model of the Juice spacecraft during electromagnetic tests at ESA's technical heart in the Netherlands (image credit: ESA–M. Cowan)

• June 7, 2018: One of the major challenges facing ESA's JUICE (JUpiter Icy Moon Explorer) will be the extreme temperatures that the spacecraft and its suite of instruments will have to endure. 15)

In order to ensure that the orbiter survives the voyage to Jupiter and the cold, hostile environment of the Solar System's largest planet, the spacecraft will have to pass a series of challenging tests during its lengthy development process. The first of these – known as a TDM (Thermal Development Model) test – was recently completed.

The objective of the test, which took place between 5 and 10 May at ESA/ESTEC in The Netherlands, was to verify that the spacecraft's thermal control system could protect the spacecraft from extreme temperatures during its complex mission.

After launch, JUICE will embark on an 88-month cruise that will make use of several flybys – of Earth, Venus, Earth, Mars, and again Earth – before leaving the inner Solar System on its way to Jupiter.

En route, the spacecraft will have to endure the effects of solar heating, particularly during the flyby of Venus. Eventually, it will have to operate in an extremely cold environment where some of its external surfaces will experience temperatures below -200º Celsius after arrival at Jupiter, with even colder conditions during solar eclipses, when the spacecraft will be in the planet's shadow.

The JUICE thermal control system is designed to minimize the impact of the external environment on the spacecraft through the use of high efficiency MLI (Multi-Layer Insulation). The material that is used to blanket the spacecraft's exterior is known as StaMet coated black kapton 160XC.

The MLI will moderate the external temperature during the spacecraft's closest approach to the Sun. It must also limit heat leakage in the cold Jupiter environment in order to minimize demand for power from the spacecraft's heaters, especially when its instruments are operating during the science and communication phases.

The power demand will be a crucial factor during operations given the limited power generated by the spacecraft's solar panels at Jupiter's distance from the Sun, where the amount of incoming solar energy is 25 times lower than on Earth.

Efficient passive thermal insulation also minimizes hardware mass – always a major concern for spacecraft designers – by reducing the need for radiators and heaters.

Thermal verification test: The thermal verification test was required to check the passive heat loss properties of the spacecraft in both cold and hot environments. It used a full scale model, the TDM, which comprised a simplified version of the JUICE flight model structure.

The spacecraft's central cylinder was replaced by a basic hexagonal structure and the HGA (High Gain Antenna) was simulated by a simple, white-painted aluminum disc with the same diameter as the HGA flight model. This was relevant for the test, because the HGA will be used as an umbrella shielding the structure when the spacecraft will be at its closest to the Sun.


Figure 8: The JUICE TDM inside the Large Space Simulator (image credit: ESA–M. Cowan)

There were no other protruding instruments or appendages on the TDM, but heat dissipation from the platform and internal instruments was simulated by adding test heaters.

The TDM itself, wrapped in MLI, was placed in the LSS (Large Space Simulator) at ESA/ESTEC (European Space Research & Technology Centre) in Noordwijk, the Netherlands. Operated by European Test Services, the LSS is the largest space simulation facility in Europe, enabling a wide variety of tests to be performed on spacecraft.

Engineers began pumping the air out of the 9.4-m diameter chamber on 5 May, in order to create a vacuum comparable to the airless environment of deep space. This vacuum was maintained throughout the test.


Figure 9: The JUICE TDM inside the Large Space Simulator, before (left) and after (right) closing the 5 m diameter side door (image credit: ESA–M. Cowan)

• April 14, 2017: NASA’s partnership in a future ESA (European Space Agency) mission to Jupiter and its moons has cleared a key milestone, moving from preliminary instrument design to implementation phase. 16)

- Designed to investigate the emergence of habitable worlds around gas giants, JUICE is scheduled to launch in five years, arriving at Jupiter in October 2029. JUICE will spend almost four years studying Jupiter’s giant magnetosphere, turbulent atmosphere, and its icy Galilean moons—Callisto, Ganymede and Europa.

- The April 6 milestone, known as Key Decision Point C (KDP-C), is the agency-level approval for the project to enter building phase. It also provides a baseline for the mission’s schedule and budget. NASA’s total cost for the project is $114.4 million. The next milestone for the NASA contributions will be the Critical Design Review (CDR), which will take place in about one year. The CDR for the overall ESA JUICE mission is planned in spring 2019.

- JUICE is a large-class mission—the first in ESA’s Cosmic Vision 2015-2025 program carrying a suite of 10 science instruments. NASA will provide the UVS (Ultraviolet Spectrograph), and also will provide subsystems and components for two additional instruments: the PEP (Particle Environment Package) and the RIME (Radar for Icy Moon Exploration) experiment.

- The UVS was selected to observe the dynamics and atmospheric chemistry of the Jovian system, including its icy satellites and volcanic moon Io. With the planet Jupiter itself, the instrument team hopes to learn more about the vertical structure of its stratosphere and determine the relationship between changing magnetospheric conditions to observed auroral structures. The instrument is provided by the Southwest Research Institute (SwRI), at a cost of $41.2 million.

- The PEP is a suite of six sensors led by the Swedish Institute of Space Physics (IRF), capable of providing a 3-D map of the plasma system that surrounds Jupiter. One of the six sensors, known as PEP-Hi, is provided by the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, and is comprised of two separate components known as JoEE and JENI. While JoEE is focused primarily on studying the magnetosphere of Ganymede, JENI observations will reveal the structure and dynamics of the donut-shaped cloud of gas and plasma that surrounds Europa. The total cost of the NASA contribution to the PEP instrument package is $42.4 million.

- The Radar for Icy Moon Exploration (RIME) experiment, an ice penetrating radar, which is a key instrument for achieving groundbreaking science on the geology, is led by the Italian Space Agency (ASI). NASA’s Jet Propulsion Laboratory (JPL), in Pasadena, California, is providing key subsystems to the instrument, which is designed to penetrate the surface of Jupiter's icy moons to learn more about their subsurface structure. The instrument will focus on Callisto, Ganymede, and Europa, to determine the formation mechanisms and interior processes that occur to produce bodies of subsurface water. On Europa, the instrument also will search for thin areas of ice and locations with the most geological activity, such as plumes. The total cost of the NASA contribution is $30.8 million.

• December 9, 2015: The mission was selected in May 2012 as the first Large-class mission within ESA's Cosmic Vision 2015–25 program, and is planned for launch in 2022 to arrive at the giant planet in 2030. 17)

- For three and a half years, JUICE will sweep around Jupiter, exploring its turbulent atmosphere, enormous magnetosphere and tenuous set of dark rings, as well as studying the icy moons Ganymede, Europa and Callisto. It will eventually go into orbit around Ganymede, a first in Solar System exploration.

- All three of these planet-sized satellites are thought to have oceans of liquid water beneath their icy crusts and should provide clues on the potential for such moons to offer habitable environments.

- Airbus Defence & Space SAS in France was announced as the prime contractor in July when ESA approved the €350 million contract.

- The contract covers the design, development, integration, test, launch campaign and in-space commissioning of the spacecraft. The Ariane 5 launch is not included and will be procured later from Arianespace.

- The 10 state-of-the-art instruments were approved by ESA in February 2013 and are being developed by teams spanning 16 European countries, the USA and Japan, under national funding.

- The spacecraft will be assembled at Airbus Defence and Space GmbH in Friedrichshafen, Germany.

• In July 2015, Airbus DS was selected by ESA (European Space Agency) as prime contractor for the design, development, production, and testing of a new spacecraft named ‘JUICE’. As its name implies (Jupiter Icy Moons Explorer), the mission will be to explore the Jovian system, focusing on three of Jupiter’s huge Galilean moons: Europa, Ganymede and Callisto, which are as large as dwarf planets and covered by an icy crust (Ref. 5).

Launch: In May 2022, Ariane 5 will lift Juice into space from Europe’s Spaceport in Kourou. A series of gravity-assist flybys at Earth (3), Venus (1) and Mars (1) will set the spacecraft on course for its October 2029 rendezvous in the Jovian system. 18)

Figure 10: This animation depicts the journey to Jupiter and the highlights from its foreseen tour of the giant planet and its large ocean-bearing moons (video credit: ESA)

Sensor complement (3GM, Gala, JANUS, J-MAG, MAJIS, PEP, PRIDE, RIME, RPWI, SWI, UVS)

ESA’s Jupiter Icy Moons Explorer, Juice, will carry the most powerful remote sensing, geophysical, and in situ payload complement ever flown to the outer Solar System (Ref. 18). 19)

The payload consists of 10 state-of-the-art instruments plus one experiment that uses the spacecraft telecommunication system with ground-based instruments. This payload is capable of addressing all of the mission's science goals, from in situ measurements of Jupiter's atmosphere and plasma environment, to remote observations of the surface and interior of the three icy moons, Ganymede, Europa and Callisto.


Figure 11: Overview of JUICE instruments (image credit: ESA/ATG medialab)

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

The instrument is a radio package comprising the KaT (Ka-Transponder), USO (ultrastable oscillator) and HAA (High Accuracy Accelerometer). The experiment will study the gravity field at Ganymede, the extent of the internal oceans on the icy moons, and the structure of the neutral atmosphere and ionosphere of Jupiter (0.1 - 800 mbar) and its moons.

PI: L. Iess, Università di Roma "La Sapienza", Italy. Lead funding agency: ASI.

GALA (GAnymede Laser Altimeter)

GALA will study the tidal deformation of Ganymede and the topography of the surfaces of the icy moons. GALA will have a 20 m spot size and 0.1 m vertical resolution at 200 km.

PI: H. Hussmann, DLR, Institut für Planetenforschung, Germany. Lead funding agency: DLR.

JANUS (optical camera system)

JANUS will study global, regional and local features and processes on the moon, as well as map the clouds of Jupiter. It will have 13 filters, a FOV of 1.3º, and spatial a resolution up to 2.4 m on Ganymede and about 10 km at Jupiter.

PI: P. Palumbo, Università degli Studi di Napoli "Parthenope", Italy. Lead funding agency: ASI.

J-MAG (JUICE Magnetometer)

J-MAG is equipped with sensors to characterize the Jovian magnetic field and its interaction with that of Ganymede, and to study the subsurface oceans of the icy moons. The instrument will use fluxgates (inbound and outbound) sensors mounted on a boom.

PI: M. Dougherty, Imperial College London, United Kingdom. Lead funding agency: UKSA, United Kingdom.

MAJIS (Moons and Jupiter Imaging Spectrometer)

MAJIS will observe cloud features and atmospheric constituents on Jupiter, and will characterize ices and minerals on the icy moon surfaces. MAJIS will cover the visible and infrared wavelengths from 0.4 to 5.7 µm, with spectral resolution of 3-7 nm. The spatial resolution will be up to 25 m on Ganymede and about 100 km on Jupiter.

PI: Y. Langevin, Institut d'Astrophysique Spatiale, France. Lead funding agency: CNES.

PEP (Particle Environment Package)

PEP comprises a package of sensors to characterize the plasma environment of the Jovian system. PEP will measure density and fluxes of positive and negative ions, electrons, exospheric neutral gas, thermal plasma and energetic neutral atoms in the energy range from <0.001 eV to >1 MeV with full angular coverage. The composition of the moons' exospheres will be measured with a resolving power of more than 1000.

PI: S. Barabash, Swedish Institute of Space Physics (Institutet för rymdfysik, IRF), Kiruna, Sweden. Lead funding agency: SNSB, Sweden.

PRIDE (Planetary Radio Interferometer & Doppler Experiment)

PRIDE will use the standard telecommunication system of the spacecraft, together with radio telescopes on Earth, VLBIs (Very Long Baseline Interferometry systems), to perform precise measurements of the spacecraft position and velocity to investigate the gravity fields of Jupiter and the icy moons.

PI: L. Gurvits, Joint Institute for VLBI in Europe, The Netherlands. Lead funding agency: NWO (Dutch Research Council) and NSO (Netherlands Space Office), The Netherlands.

RIME (Radar for Icy Moons Exploration)

RIME is an ice-penetrating radar to study the subsurface structure of the icy moons down to a depth of around nine kilometers with vertical resolution of up to 30 m in ice. RIME will work at a central frequency of 9 MHz (1 and 3 MHz bandwidth) and will use a 16 m antenna.

PI: L. Bruzzone, Università degli Studi di Trento, Italy. Lead funding agency: ASI.

RPWI (Radio and Plasma Wave Investigation)

The instrument will characterize the radio emission and plasma environment of Jupiter and its icy moons using a suite of sensors and probes.

RPWI will be based on four experiments, GANDALF, MIME, FRODO, and JENRAGE. It will use a set of sensors, including two Langmuir probes to measure DC electric field vectors up to a frequency of 1.6 MHz and to characterize thermal plasma and medium- and high-frequency receivers, and antennas to measure electric and magnetic fields in radio emission in the frequency range 80 kHz- 45 MHz.

PI: J.-E. Wahlund, Swedish Institute of Space Physics (Institutet för rymdfysik, IRF), Uppsala, Sweden. Lead funding agency: SNSB, Sweden.

SWI (Sub-millimeter Wave Instrument)

The objective of SWI is to investigate the temperature structure, composition and dynamics of Jupiter’s atmosphere, and the exospheres and surfaces of the icy moons. SWI is a heterodyne spectrometer using a 30 cm antenna and working in two spectral ranges 1080-1275 GHz and 530-601 GHz with spectral resolving power of ~107.

PI: P. Hartogh, Max-Planck-Institut für Sonnensystemforschung, Germany. Lead funding agency: DLR, Germany.

UVS (UV imaging Spectrograph)

The aim of UVS is to characterize the composition and dynamics of the exospheres of the icy moons, to study the Jovian aurorae, and to investigate the composition and structure of the planet’s upper atmosphere. The instrument will perform both nadir observations and solar and stellar occultation sounding.

UVS will cover the wavelength range 55-210 nm with a spectral resolution of <0.6 nm. The spatial resolution will reach 0.5 km at Ganymede and up to 250 km at Jupiter.

PI: R. Gladstone, SwRI (Southwest Research Institute), USA. Lead funding agency: NASA.


2) ”Science Objectives,” ESA, URL:

3) O. Grasset, M. K. Dougherty, A. Coustenis, E. J. Bunce, C. Erd,D. Titov, M. Blanc, A. Coates,P. Drossart, L. N. Fletcher, H. Hussmann, R. Jaumann, N. Krupp, J.-P. Lebreton, O. Prieto-Ballesteros, P. Tortora, F. Tosi, T. Van Hoolst, ”JUpiter ICy moons Explorer (JUICE): An ESA mission to orbit Ganymede and to characterize the Jupiter system,” Planetary and Space Science, Volume 78, April 2013, Pages 1-21, URL:

4) ”JUICE is Europe’s next large science mission,” ESA, 2 May 2012, URL:

5) Juice - Searching for life on jupiter’s icy moons,” Airbus, July 2015, URL:

6) ”JUICE ground control gets green light to start development of Jupiter operations,” ESA, 16 January 2018, URL:

7) P. Zanella, F. Faleg, M. Molina, A. Polli, S. Riva, E. Ferrando, R. Romani, E. Bongers, M. Kroon, H. Klinkspoor,T. Boers, T. Schirmann, C. Lebranchu, C. Sabourin, A. Calvel , S. Verstaen, C. Baur, ”The JUICE Photovoltaic Assembly,” Proceedings of the 69th IAC (International Astronautical Congress) Bremen, Germany, 1-5 October 2018, paper: IAC-18-C3.4.4, URL:

8) ”CERN simulating Jupiter,” ESA, 28 August 2019, URL:

9) ”Jupiter mission takes first images of destination – from Earth!,” ESA, 22 August 2019, URL:

10) ”Arianespace and ESA announce Jupiter Icy Moons Explorer launch contract,” ESA Space Science, 17 June 2019, URL:

11) ”Review board gives JUICE the all clear,” ESA, 3 April 2019, URL:

12) ”Juice’s magnetometer boom,” ESA, Technology image of the week, 20 March 2019, URL:

13) ”JUICE engineering model ready for testing,” ESA Science & Technology, 11 December 2018, URL:

14) ”Testing the radar antenna for Juice,” ESA, 12 November 2018: URL:

15) ”#1: JUICE comes in from extreme temperature test,” ESA, 7 June 2018, URL:

16) ”NASA Approves Instruments for ESA’s ‘JUICE’ Mission to Jupiter System,” NASA 14 April 2017, URL:

17) ”Jupiter mission contract ceremony — ESA and Airbus Defence & Space today marked the signing of the contract for building JUICE, the JUpiter ICy moons Explorer,” ESA, 9 December 2015, URL:

18) ”Juice’s Jovian odyssey,” ESA, 5 February 2019, URL:

19) ”JUICE Science Payload,” ESA, Science & Technology, 5 February 2019, URL:

The information compiled and edited in this article was provided by Herbert J. Kramer from his documentation of: ”Observation of the Earth and Its Environment: Survey of Missions and Sensors” (Springer Verlag) as well as many other sources after the publication of the 4th edition in 2002. - Comments and corrections to this article are always welcome for further updates (

Spacecraft     Development Status     Launch     Sensor Complement    References    Back to Top