Valéry Lainey and his team from the Paris Observatory-PSL have made a groundbreaking discovery that has added Mimas, one of Saturn’s smallest moons, to an exclusive club of moons with internal oceans. However, unlike Enceladus and Europa, the ocean on Mimas is remarkably young, estimated to be only 5 to 15 million years old.
The early age of the ocean was determined through detailed analysis of Mimas’ tidal interactions with Saturn. This suggests that the ocean formed recently based on the discovery of an unexpected irregularity in its orbit. The presence of a hidden ocean on Mimas provides a unique window into the early stages of sea formation and the potential for life to emerge.
The discovery was made possible by analyzing data from NASA’s Cassini spacecraft, which meticulously studied Saturn and its moons for over a decade. By closely examining subtle changes in Mimas’ orbit, researchers were able to infer the presence of a hidden ocean and estimate its size and depth.
Lainey said: “This has been a great team effort with colleagues from five different institutions and three countries working together under my leadership to discover another fascinating and unexpected feature of the Saturn system.” The discovery of the young Mimas ocean has important implications for our understanding of potential life beyond Earth. It suggests that even small, seemingly inactive moons may harbor hidden oceans capable of supporting conditions essential for life according to the authors.