British scientists are to play a key role in a one billion euro (£812 million) space mission to explore the icy moons of Jupiter.
The Juice (Jupiter Icy Moons Explorer) mission will investigate the possibility of "waterworlds" that may harbour life.
Its primary target is Ganymede, the Solar System's biggest moon, which is 8% larger than the planet Mercury.
Ganymede is thought to conceal a deep ocean of salty water beneath a thick crust of ice.
It also has its own magnetic field, offering protection against Jupiter's powerful radiation belts, and an ancient surface littered with many types of crater.
The plan is to send a probe into orbit around Ganymede to study its sub-surface ocean and assess whether life could exist there.
The Juice spacecraft will also make fly-bys of two other moons, Callisto and Europa, which are also believed to have ice-covered oceans.
Juice is scheduled to launch in 2022 and will take eight years to make the long journey to Jupiter.
After its arrival in 2030 the spacecraft will spend three years collecting data to be transmitted back to Earth.
The mission was approved by the European Space Agency (ESA) at a meeting in Paris. It will be the first European-led space mission to the outer Solar System.