Saturn’s ocean moon looks more hospitable to subsurface life than we thought

Mars isn’t our only neighbor that may harbor life. The odds have risen that Saturn’s moon Enceladus may, too. On Wednesday, scientists published a paper outlining the increasing complexity of molecules emitted from beneath the moon’s surface. “We now have all elements required for Enceladus to harbour life,” the ESA’s Dr Jörn Helbert told The Guardian.

Enceladus gives researchers a unique window into its subsurface world. The Cassini mission already taught us that plumes of water ice shoot 6,000 miles into space from Enceladus. The source of those icy jets is believed to be a subsurface saltwater ocean, around 30 miles deep, that envelops the entire moon. The space geysers shoot out from its South Pole.

Previous analysis of the moon’s icy particles already revealed the chemical building blocks for life as we know it. But before, the organics were inferred from studying Saturn’s E ring, which is composed mostly of material from the icy jet. In contrast, this study looked at data from the Cassini mission’s flyby of the plumes themselves. What’s different today is the variety of organic signatures and the freshness of the samples. “These grains were just minutes old,” lead author Dr. Nozair Khawaja told The Guardian.

“The detection of organics directly in the plume rules out space weathering as the sole production pathway,” the paper’s authors wrote. Space weathering refers to radiation and other processes that potentially alter or spoil the samples. “The grains are fresh, unaltered and proof of survival through ocean transit and plume emission” for the compounds.

“These grains were just minutes old,” Khawaja said. “It means that what we are capturing here is actually the pure sample from the subsurface.” He said the results also increased the known complexity of Enceladus’ sub-surface organic chemistry. “When there is complexity happening, that means that the habitable potential of Enceladus is increasing right now,” he said.

The results still don’t prove that there’s life on Saturn’s moon. However, they do suggest a chemically rich subsurface ocean that could seed the building blocks of life. Your move, Mars.