Jupiter's moon Europa may have signs of life in its buried ocean — but can we get to them?

This view of Jupiter's icy moon Europa was captured by JunoCam, the public engagement camera aboard NASA's Juno spacecraft, during the mission's close flyby on Sept. 29, 2022.

(Image credit: Image data: NASA/JPL-Caltech/SwRI/MSSS | Image processing: Kevin M. Gill CC BY 3.0)

NASA's Europa Clipper is currently on a 1.8-billion-mile journey to Jupiter, tasked with assessing whether the icy moon of its namesake, Europa, could support life.Based on data from the historic Voyager and Galileo missions, scientists know Europa hides a global ocean beneath its frozen crust, containing more than double the water of all Earth's oceans combined. During the Europa Clipper's planned 49 close flybys of the icy moon, planetary scientists hope the spacecraft detects giant water plumes or warm surface pockets supplied by this subterranean ocean, offering a convenient way to analyze the hidden ocean's chemistry from orbit.A new study, however, suggests any shallow water the Europa Clipper detects may not necessarily be a direct window into Europa's ocean after all.Research led by planetary scientist Lujendra Ojha of Rutgers University indicates that Europa's icy shell acts as a far more formidable barrier than previously assumed. Computer simulations modeling the physics of water traveling through fractures in the ice reveal that liquid rising from the ocean would move turbulently, shed heat rapidly and freeze the cracks shut — often in a matter of hours — long before reaching shallow depths."There's an icy shell, there's water underneath, and there's all this speculation about how that water can come from deep underground and make its way all the way up without freezing en route," Ojha said in a statement. "That's really what we think we disproved."To test this scenario, Ojha's team built computer simulations to evaluate whether ocean water could rise through fractures in the crust and collect in shallow reservoirs closer to the surface. Such reservoirs, if fed directly by the ocean, would be significantly easier for passing spacecraft to detect and analyze than an ocean buried miles below.While earlier models assumed water would flow smoothly through these pathways, real-world physics creates a far more chaotic journey, according to the new study. Instead of a steady stream, rising water churns turbulently against the frigid walls of the fractures, rapidly losing heat."It's going to be left and right, it's going to be up and down, it's going to have a swirling motion," Ojha said in the statement. "And when that happens, that liquid water is going to cool very, very fast as it approaches the surface."