Saturn’s sixty-two moons continue to be a treasure trove of cosmic mysteries. Earlier this year, NASA astronomers discovered deep canyons on Titan that flow with liquid hydrocarbons, spurring comparisons with Earth’s geography. That same moon was then the site of mysterious ice clouds which appeared suddenly, implying atmospheric conditions much closer to Earth’s than previously thought. Now, new data collected by the Royal Observatory of Belgium shows that the Saturnian moon Dione contains a surprising find: a liquid ocean.
That conclusion was reached after astronomers analyzed gravitational and geological data that showed anomalies that didn’t match current thinking about the composition of Dione, the fifteenth largest moon in our solar system. According to their research published in Geophysical Research Letters, the astronomers believe these anomalies could only be explained by a deep subsurface ocean under Dione’s surface:
Its gravity and shape can be explained in terms of a 99 ± 23 km thick isostatic shell overlying a 65 ± 30 km thick global ocean, thus providing the first clear evidence for a present-day ocean within Dione.
Dione’s ocean is thought to lie far below the surface composed of ice and silicate rock and stretch deep beneath Dione’s icy surface. Another one of Saturn's moons, Enceladus, is thought to have a similar subterranean ocean.
What’s more exciting than the discovery of Dione's ocean itself is the fact that the ocean is housed within a layer of rock, creating the conditions believed to be responsible for sparking life on Earth. Attilio Rivoldini, co-author of the published research, believes the discovery could be ground-breaking in the search for life outside Earth:
The contact between the ocean and the rocky core is crucial. Rock-water interactions provide key nutrients and a source of energy, both being essential ingredients for life.
Good thing NASA’s already working on that deep space submarine. Who knows what kind of terrifyingly awesome alien sea creatures might be down there.