Pleasant rivalries can’t assist however prolong all the way in which to Saturn, even with one thing as esoteric as saltwater worlds.
Although there are a lot of impartial events, Europa lovers and followers of Saturn’s moon Enceladus are usually blissful to debate with one another — and the occasional bystander — about which one is extra prone to harbor life. A significant promoting level for Enceladus is that a few of its ocean spray has already been sampled, and the findings up to now have been compelling.
Whereas a handful of spacecraft have visited the Saturn system, it was NASA’s Cassini mission that gave us probably the most unprecedented element of Enceladus’ ocean. Between 2008 and 2015, the spacecraft swept by way of the moon’s plumes, straight sampling its ocean spray. Whereas it didn’t detect life, Cassini’s discoveries have elucidated Enceladus’ ocean, making it an much more tantalizing vacation spot for future examine.
“Cassini principally sniffed Enceladus’ plumes,” Ahrens mentioned. “What it discovered was not solely proof of liquid salt water but additionally that it was heat.”
One other crucial discovering was that Enceladus’ subsurface ocean has hydrothermal vents on its seafloor. It appears that evidently as Saturn and probably the planet’s moon Dione pull on Enceladus, the tiny moon flexes, inflicting materials from these vents to eject out of fissures on Enceladus’ Southern Hemisphere. Via these so-called “tiger stripes,” ocean spray blasts into area.
Although scientists are nonetheless combing by way of Cassini knowledge, it has additionally change into clear that Enceladus’ ocean accommodates molecular hydrogen — which NASA has referred to as “sweet for microbes” — in addition to different constructing blocks for all times, Iike carbon dioxide and methane. On paper, it’s fairly just like the situations that allowed ocean life to propagate on early Earth.
Sadly, no area company has introduced concrete plans to return to Enceladus. But when life is likely to be feasting across the moon’s hydrothermal vents, maybe extra scientific snuffling is required to verify.