Their destination may be the same, but ESA’s Jupiter Icy Moons Explorer (Juice) and NASA’s Juno and Europa Clipper are all unique missions with different objectives, orbits and instruments. Juno’s discoveries are already being used to optimise plans for Juice and Europa Clipper.
Since arriving at Jupiter in July 2016, NASA’s Juno mission has been orbiting the gas giant every 53 days, capturing stunning high-resolution snapshots as it goes. Juice will complement Juno by taking a more global view, continuously watching Jupiter as a whole system to monitor how its ever-changing atmosphere and auroras evolve over time, from minutes to days to years.
Europa Clipper is due to arrive at the Jovian system in 2030 to focus on the moon Europa, including investigating whether the icy moon could have conditions suitable for life. Juice, on the other hand, will study many targets (three icy moons, Jupiter's atmosphere, magnetosphere, Io, smaller moons, Jupiter's rings) with a special focus on Ganymede.
Having two missions in the Jupiter system at the same time is a great opportunity for science. The Europa Clipper science team and Juice science team are already working together to maximise the scientific harvest of the two missions. A joint meeting is organised approximately once per year and the two teams are in regular contact in between meetings. Recently, a steering group was formed that is dedicated to this collaboration, including members of both teams.
Juice will make detailed observations of Jupiter and its three large ocean-bearing moons – Ganymede, Callisto and Europa – with a suite of instruments. The mission will characterise these moons as both planetary objects and possible habitats, explore Jupiter’s complex environment in depth, and study the wider Jupiter system as an archetype for gas giants across the Universe.