The European Space Agency's next mission will be known as JUICE -- Jupiter Icy moons Explorer -- an attempt to see what lies on and around the alien worlds of Europa, Ganymede and Callisto.
There's going to be a bit of a wait for results, though. JUICE is tentatively scheduled to launch from Europe’s Kourou spaceport in 2022, before spending eight years travelling across our solar system to Jupiter. Then it'll have to find somewhere to park.
If it survives that, JUICE will then spend three years observing Jupiter's varied and exciting moons, examining conditions beneath their icy surfaces, taking in an orbit of Callisto, making two passes of Arthur C. Clarke's favourite Europa, before eventually orbiting Ganymede. [ESA]