JUICE
What is JUICE?
Probes & telescopes· Launched 2023-04-14 – arrival 2031-07 planned (cruising). ESA's spacecraft to Jupiter's icy moons. It is due to reach Jupiter in 2031 and to settle into orbit around the moon Ganymede in 2034.
Mission timeline
Spacecraft specs
| Launch | 2023-04-14 |
|---|---|
| Flybys | Moon–Earth 2024-08 · Venus 2025-08 · Earth 2026-09, 2029-01 |
| Jupiter arrival | 2031-07 (planned) |
| Target | Ganymede orbiter (2034) |
Figures are representative approximations. Source: compiled from NASA and IAU public data.
How JUICE, built for cold Jupiter, survived hot Venus
JUICE was built for the cold, dim surroundings of Jupiter, yet its route took it past Venus in August 2025. Sunlight near Venus is about twice as strong as at Earth and about fifty times stronger than at Jupiter. The spacecraft therefore flew past Venus with its large dish antenna turned toward the Sun as a parasol, keeping the main body in shade.
At Jupiter the problem is the reverse: sunlight is so weak that electricity is hard to come by. JUICE's solar arrays cover 85 square metres, among the largest on any planetary probe, yet near Jupiter they will produce only about 850 watts, barely enough to run a microwave oven.
Soon after launch the 16 m antenna of the ice-penetrating radar failed to unfold because a retaining pin had stuck. Controllers shook the spacecraft and warmed the mechanism in sunlight, and in May 2023, about three weeks later, a jolt from a small actuator freed the pin and the antenna opened.
The mission in depth
JUICE stands for JUpiter ICy moons Explorer. Jupiter's large moons Ganymede, Europa and Callisto are covered in thick ice, and oceans are thought to lie beneath it. JUICE aims to find out whether these icy moons could offer conditions suitable for life.
JUICE was launched on 14 April 2023 on an Ariane 5 rocket. It cannot fly straight to Jupiter, so it gains speed by passing planets several times. In August 2024 it became the first spacecraft to fly past the Moon and then Earth a day apart, and in August 2025 it passed Venus. It passes Earth again in September 2026 and January 2029 before heading for Jupiter.
It reaches Jupiter in July 2031. Over the following years it is planned to make two close passes of Europa, twenty-one of Callisto and twelve of Ganymede while orbiting Jupiter. In December 2034 it enters orbit around Ganymede. If all goes to plan, it will be the first spacecraft to orbit the moon of another planet.
NASA's Europa Clipper arrives at Jupiter at about the same time. Clipper focuses on repeated flybys of Europa, while JUICE settles at Ganymede for a detailed study. Together the two missions will allow a much broader comparison of Jupiter's icy moons.
Frequently asked
- When did JUICE launch?
- JUICE was launched on 2023-04-14.
- What is the next milestone for JUICE?
- Next for JUICE, on 15 Jul 2031: JUICE arrives at Jupiter.
- In one line, what is JUICE?
- Probes & telescopes — ESA's spacecraft to Jupiter's icy moons.
Related
Figures are representative approximations. Simulated positions use J2000 mean elements.