Indications of Possible Life on Enceladus, One of Saturn’s Moons

Oct. 6—Analysis of the material gathered from the Cosmic Dust Analyzer (CDA) of NASA’s 1997 Cassini mission has indicated the possibility of life on Enceladus, one of Saturn’s moons. Cassini performed years-long flybys of Enceladus while in orbit around Saturn and discovered that Enceladus is covered in a 16- to 19-miles thick shell of highly reflective ice, which hides a global saltwater ocean. Fissures in the ice were spewing into space, forming part of Saturn’s E-ring. Some of this material was picked up by Cassini. “The high-speed flyby of Enceladus enabled us to identify new compounds that were not found in the E ring data, most notably esters, alkenes, and ether compounds,” Fabian Klenner, a University of Washington postdoctoral researcher of Earth and space sciences and a member of the research team, and who helped validate the new CDA results, was quoted as saying Oct. 3. “Notably, esters and ethers can be part of lipids, and lipids are key to life as we know it.”

JPL’s Vyacheslav Turyshev noted that the particles analyzed by Cassini came from the depths of Enceladus and are not yet contaminated. “The fact that the particles are fresh is important: it’s an argument that the organic matter actually came from the depths of the Earth, and wasn’t produced or destroyed in Saturn’s E-ring,” he said in an interview with Komsomolskaya Pravda. Turyshev, however, was not so quick in making a claim for this being a sign of life on Enceladus.

“No, this isn’t proof of life. It’s a demonstration that the ocean contains a rich organic chemistry consistent with hydrothermal conditions and potential prebiotic pathways. If I were to give a numerical estimate, I would describe the probability of microbial life as non-zero, but moderate—in the single digits to tens of percent—until we see direct biosignatures (i.e., signs of life),” said Turyshev.