JUICE Mission: Exploring Jupiter’s Moons


The Jupiter Icy Moons Explorer (JUICE) is set to embark on an eight-year mission to Jupiter and its moons. The European Space Agency (ESA)-led mission will explore three of Jupiter’s moons, Ganymede, Callisto, and Europa, which are believed to have huge oceans of water under their icy surfaces. Scientists believe that these oceans could support living organisms. JUICE will be launched by the Arianne 5 rocket, which was previously used to launch the James Webb Space Telescope. The mission was scheduled to take off on Thursday but was delayed due to lightning risk.

Jupiter is the largest planet in the solar system and has 80 to 95 moons orbiting it, according to NASA. JUICE will investigate Jupiter’s gaseous complex surface in depth and its relationships with the oxygen and icy sub-surface saltwater ocean moons. The orbiter will have 10 state-of-the-art instruments on board that are some of the most powerful ever sent into the solar system. Nine of the instruments are led by European partners and one by NASA. By July 2031, the spacecraft will have entered Jupiter’s orbit, from which it will probe Ganymede, Europa and Callisto.

JUICE will explore three of Jupiter’s largest moons – Ganymede, Callisto and Europa. There is hope that Jupiter’s icy moons will have some kind of living organisms, said Carole Larigauderie, JUICE project head at French space agency CNES. Ganymede is the largest moon in the solar system, according to NASA, and Earth is about 2.4 times bigger than it. It is larger than the planet Mercury. It is the only moon in the solar system that possesses its own magnetic field, like Earth. JUICE is expected to reach Ganymede’s orbit by 2034, where it will fly by the planetary mass 12 times. The mission’s main goals for Ganymede are to explore its magnetic field and hidden ice ocean and study its habitability.

Callisto is believed to have the oldest surface in the solar system. Earth is about 2.6 times the heavily cratered object, according to NASA. JUICE is expected to fly by Callisto 21 times and get as close as 200km (124 miles) to it. Once there, it will study the environment around early Jupiter. Europa, according to NASA, is about 4.1 times the size of Earth and is believed to have a young and active surface that may vent water vapour to space via plumes and geysers. JUICE will make two flybys around Europa to search for any pockets of water, explore the surface, and look for any signs of activity.

If one or more of Jupiter’s moons tick all the boxes to host life, the “logical next step” would be to send a mission to land on the surface, said Cyril Cavel, JUICE project manager at manufacturer Airbus. Although there are no plans for such a mission, which could definitively prove the existence of life beyond Earth, “that’s part of the dream”, he said. Nicolas Altobelli, a JUICE project scientist at ESA, said it would be “the first time that we explore habitats beyond the frost line” between Mars and Jupiter. Beyond that line, temperatures plummet and “liquid water can no longer exist on the surface”, Altobelli told AFP news agency earlier this year.

JUICE is the first mission by the ESA to a Jovian orbit system and the first mission to a moon other than Earth’s. There have been seven missions to Jupiter so far. NASA’s Juno is still ongoing, and its Clipper is set to launch later this year. The mission is significant as it could provide insight into the possibility of life beyond Earth. If JUICE discovers that one or more of Jupiter’s moons could support life, it could change the way we view the universe and our place in it.