The European Space Agency has approved its first Large Class mission-- a sophisticated probe to study the four Galilean moons of Jupiter and how they interact with the giant planet. The mission will be called JUICE.
JUICE is scheduled to launch in 2022 and take eight years to reach the Jovian system. If all goes well, it will tour the moons for three years, studying them in unprecedented detail. The four are big and bright enough that they were discovered by Galileo in 1610, and they are a fascinating quartet. Io is the most volcanically active body in the Solar System, while Callisto is the most heavily cratered. Europa likely has a huge ocean-- and possibly life-- under its icy shell, and Ganymede is the largest moon in the Solar System. It even has a magnetic field.
The mission is budgeted at $1.1 billion. Despite Europe's current economic weakness, ESA is pushing ahead. That's in stark contrast to what has happened in the United States, where NASA is suffering cuts to its planetary exploration program, especially that part dealing with the outer planets.