Hydrothermal activity on Enceladus

This artist's impression shows Saturn's icy moon Enceladus. With a frozen surface covering a deep ocean, Enceladus is a fascinating target to search for signs of habitability elsewhere in our Solar System.

Hydrothermal vents in the moon's ocean floor release heated water, laden with minerals and dissolved gases. This mixture of warm water and rocky material rise through the ocean towards the moon's ice shell, where it melts the ice and escapes onto space.

Some of Enceladus's secrets were already revealed by the NASA/ESA/ASI Cassini-Huygens mission. ESA is now studying a dedicated mission to Enceladus. Planned for launch in the 2040s, the mission would fly through the jets and even land on the moon's south polar terrain to collect samples.

Enceladus ticks all the boxes to be a habitable environment that could support life: the presence of liquid water, a source of energy, a specific set of chemical elements and complex organic molecules. A mission that takes measurements directly from the moon’s surface, seeking out signs of life, would offer Europe a front seat in Solar System science.

[Image description: Scientific illustration showing a cross-section of Saturn’s moon Enceladus. It features three labelled layers: An ice shell at the top, with visible cracks releasing jets of water vapour into space; an ocean in the middle, depicted as a large body of water beneath the ice; a rocky core at the bottom, shown emitting heat that may drive the jets. In the background, Saturn and its rings are visible in space.]