Searching for life in alien oceans may be more difficult than scientists previously thought, even when we can sample these extraterrestrial waters directly.

A new study focusing on Enceladus, a moon of Saturn that sprays its ocean water into space through cracks in its icy surface, shows that the physics of alien oceans could prevent evidence of deep-sea life from reaching places where we can detect it.

Published today (Thursday, 6 February 2025) in Communications Earth and Environment, the study shows how Enceladus’s ocean forms distinct layers that dramatically slow the movement of material from the ocean floor to the surface.