A methane-producing Earth microbe grew in a laboratory mixture designed to resemble the ocean beneath Saturn’s moon Enceladus, researchers reported in a study published in Science Advances.
The experiment tests whether an environment could support life. It does not establish that organisms live on the moon.
What happened in the laboratory?
According to Freie Universität Berlin’s September 25 account, researchers recreated alkaline, carbonate-rich conditions and interactions between water and rock. Methanothermococcus okinawensis continued growing in that mixture, using hydrogen from the reactions to produce methane despite scarce dissolved carbon dioxide.
The study was led by researchers at Ludwig-Maximilians-Universität München, with collaborators from Berlin.
Why Enceladus attracts attention
The ocean is not a new discovery. A 2015 analysis of seven years of Cassini observations found that the moon’s measured wobble was too large for its icy surface to be rigidly connected to its core. That supported a global subsurface ocean rather than a small polar reservoir.
A separate new study of plume ice grains suggests that freezing and fragmentation can concentrate different substances in individual particles. Future spacecraft could use those particles to look for possible biological material.
The two findings address different questions: whether familiar biology can function in a simulated environment, and how a mission might sample an ocean. Neither supplies the missing observation of life itself.