NASA takes this detergent brand to outer space Even though NASA's Cassini mission ended around four years ago, data collected by this probe about Saturn and its moons still continue to perplex researchers. And now, a recent study carried out using the data obtained by the Cassini mission has apparently found possible signs of alien life on Saturn's moon Enceladus. Is methane a sign of alien life? In a new study published in Nature Astronomy, researchers from the University of Arizona and Paris Science and Letters University revealed that they have detected methane in the plumes of Saturn's icy moon Enceladus. It is still unclear how this methane is produced, but researchers believe that it could be coming out from activity at hydrothermal vents present on Enceladus's interior seafloor.