Shoot for the moons: inside ESA's JUICE mission

Among the many intriguing aspects of Jupiter, drawing fascination from scientists eager to discover more about our solar system’s largest planet, are its large icy moons. More than 75 moons are known to orbit the planet, but three of its biggest– Europa, Callisto and Ganymede –  are the focus of the European Space Agency (ESA)’s Jupiter Icy Moons Explorer mission, dubbed ‘JUICE’.

The ’gas giant’ Jupiter has a complex environment, with no Earth-like surface and an atmosphere made up mainly of hydrogen and helium. While this makes the planet itself hostile to life, these three major moons are thought to bear oceans beneath their icy crusts which could be capable of supporting it.

JUICE will see a particular focus on the largest of these, Ganymede – the largest moon in the solar system and, uniquely, the only one with its own magnetic field.

“To understand this question of habitability, we need to explore the Jupiter system…we study Jupiter, its atmosphere, its weather, its magnetic field, the volcanic moon Io, the other moons … and how all these bodies are connected to each other,” said Olivier Witasse, JUICE project scientist at ESA, during a pre-launch briefing event in April.