Q&A WITH A PLANETARY LIFE EXPERT

Saturn's icy moon Enceladus boasts water, heat and organics. Now scientists have discovered it has complex chemistry too. Could it prove to be habitable?

- Nozair Khawaja

What is Enceladus?

Enceladus is a medium-sized moon of Saturn made up of a crust of water-ice and an ocean of liquid water below. This ocean is in some senses similar to those on Earth and is connected directly to Enceladus's rocky core. Water from Enceladus's ocean is emitted in large jets through cracks in the icy crust near the moon's south pole.

What causes these jets?

They happen because Enceladus is orbiting a much larger body: Saturn. Saturn's gravitational pull causes Enceladus to stretch, compress and relax, which gives rise to an immense amount of friction.

This friction is converted into heat, which causes interactions between the water and rock and hydrothermal vents at the bottom of Enceladus's ocean. These vents in turn push material to the top of the ocean, where it bursts through the cracks as plumes of water vapour and ice grains. These plumes can be enormous, reaching thousands of kilometres above the moon's surface.

Why are scientists interested in Enceladus?