Beneath Titan’s foggy atmosphere, liquid methane rains down, forming lakes on the frozen surface. In fact, Titan is the only other body in our solar system known to have liquid on the surface. Analyzing data from NASA’s Cassini space probe, scientists were hopeful that there might be liquid water beneath its icy shell as well. Initial observations of Saturn’s planet-like moon showed significant smushing and stretching as it traveled its elliptical orbit—a good sign of a vast interior ocean, slumbering beneath the ice. And that raised hopes that Titan hosted life.
But research published today in Nature is throwing cold water on the hidden ocean theory. “The deformation we detected during the initial analysis of the Cassini mission data could have been compatible with a global ocean, but now we know that isn’t the full story,” University of Washington planetary scientist and study co-author Baptiste Journaux said in a statement.
Read more: “Why We Might Not Find Life on Titan”
To arrive at this new conclusion, researchers looked at the timing of Titan’s smushing and stretching and determined it lagged behind Saturn’s peak gravitational pull by about 15 hours. If Titan’s icy shell was hiding a purely liquid ocean, its shape would change much more quickly.
So what does Titan’s interior look like? With this new data, scientists believe it’s much more viscous, made up of slush, ice, tunnels, and pockets of melt water surrounding its rocky core.
With no ocean, you might think scientists’ hopes of finding life on Titan were dashed. Instead, they’re more optimistic than before.
“Instead of an open ocean like we have here on Earth, we’re probably looking at something more like Arctic sea ice or aquifers, which has implications for what type of life we might find, but also the availability of nutrients, energy, and so on,” Journaux added.
Smaller pockets of liquid water—some of which could reach a balmy 68 degrees Fahrenheit—can concentrate collections of life-sustaining nutrients, improving the odds simple organisms could evolve.
Titan might be freezing cold, but the search for life there is heating up. 
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Lead image: NASA
