MADRID, 7 Feb. (EUROPA PRESS) –
Hidden beneath the cratered surface of Mimas, one of Saturn’s smallest moons, lies a global ocean of liquid water.
This surprising discovery, led by Dr. Valéry Lainey of the Paris Observatory-PSL and published in the journal Nature, reveals a “young” ocean formed just 5 to 15 million years ago, making Mimas — the moon reminiscent of the ‘Death Star’ from the ‘Star-Wars’ saga– in a primary objective to study the origins of life in our Solar System.
“Mimas is a small moon, only about 400 kilometers in diameter, and its cratered surface did not reveal the hidden ocean beneath,” says Dr. Nick Cooper, co-author of the study and honorary researcher at the Astronomy Unit of the School of Physical and Chemical Sciences, Queen Mary University of London.
“This discovery adds Mimas to an exclusive club of moons with internal oceans, including Enceladus and Europa, but with a unique difference: its ocean is remarkably young, estimated to be only 5 to 15 million years old.”
This early age, determined through detailed analysis of Mimas’s tidal interactions with Saturn, suggests that the ocean formed recently, based on the discovery of an unexpected irregularity in its orbit. As a result, Mimas provides a unique window into the early stages of ocean formation and the potential for life to emerge.
“The existence of a newly formed liquid water ocean makes Mimas an ideal candidate for study by researchers investigating the origin of life,” explains Dr. Cooper. The discovery was made possible by analysis of data from NASA’s Cassini spacecraft, which meticulously studied Saturn and its moons for more than 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.
Dr Cooper continues: “This has been a huge team effort, with colleagues from five different institutions and three different countries coming together under the leadership of Dr Valéry Lainey to discover another fascinating and unexpected feature of the Saturn system, using data from the Cassini mission.
The discovery of the young Mimas ocean has important implications for our understanding of the potential for 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.
