In 2005, the Cassini probe discovered eruptions of water vapor and ice particles at Enceladus’ south pole. Images from the spacecraft showed that the jets originated from fractures dubbed “tiger stripes,” and that they were a major source of the material in Saturn’s E ring.
On March 12, 2008, Cassini made a flyby of the moon, cruising directly through a plume and sampling the material being ejected. Analysis revealed a complex mixture of water vapor and volatile gases, carbon dioxide and carbon monoxide, and organic materials. The plumes and their ejecta helped scientists draw several conclusions: that Enceladus has a global underground saltwater ocean, that the moon is hydrothermally active, and that the ice in the plumes contain organic molecules. Taken as a whole, the information Cassini delivered at Enceladus suggests that the moon is potentially habitable.
