**Europa’s Concealed Ocean: A Revised View on Possible Life**
For many years, researchers have imagined Europa, one of Jupiter’s moons, as a sanctuary for extraterrestrial microorganisms flourishing around hydrothermal vents deep within a concealed ocean, reminiscent of Earth’s deep-sea habitats. Nevertheless, recent studies indicate a dramatically different scenario: Europa’s ocean floor may be geologically static, lacking active fractures, volcanic activity, or the chemical energy necessary to sustain life.
A study spearheaded by planetary scientist Paul Byrne from Washington University in St. Louis concludes that the current forces acting on Europa are insufficient to break its rocky core. This geological inactivity could lead to a stagnant oceanic environment with no fresh mineral exchanges—a stark deviation from Earth’s tectonic dynamics that invigorate deep-sea ecosystems. Europa appears to be devoid of such a dynamic force.
In their investigation, the team evaluated stresses from Jupiter’s gravitational influence, Europa’s cooling interior, and sluggish mantle convection. Even with tidal flexing—occurring every 84 hours—the calculated stress was inadequate. The daily tide only contributes about three percent of the required force to reactivate faults. Europa would need to contract considerably to induce seafloor fractures, yet there are no indications of recent contraction.
“If we were able to investigate that ocean with a remote-controlled submersible, we expect we wouldn’t observe any newly formed fractures, active volcanoes, or jets of hot water on the ocean floor,” asserts Byrne.
**Negligible Stress on Europa’s Ocean Floor**
The researchers adopted a cautious approach in their modeling, assuming earlier tectonic activity had compromised the ocean floor. Yet, despite this assumption, the existing forces are profoundly insufficient to fracture rocks at the boundary of brittle and ductile layers. For example, mantle convection stress is around 150 kilopascals, while rock fracture demands over 51 megapascals—over two orders of magnitude short.
Furthermore, Europa’s mantle is remarkably small—approximately half the size of Mars’—restricting its ability to churn and instigate active geology. In the absence of mantle movement or contraction, the seabed remains under compressive stress, constrained by the enormous ocean and ice above.
**Consequences for the Search for Life**
An inactive seafloor does not rule out the possibility of life but shifts the focus of scientists in their quest for energy sources. If life does exist in Europa’s waters, it probably does not depend on hydrothermal circulation as it does on Earth. Instead, life may rely on slower processes such as radiolysis, which entails radioactive decay breaking down water molecules into hydrogen and oxygen.
Definitive answers may emerge in 2031 when NASA’s Europa Clipper arrives to examine Jupiter’s moon. Although it will not land or penetrate the ice, the spacecraft will map Europa’s gravitational field and surface characteristics, potentially validating the inactivity of the seafloor or revealing unexpected findings beneath.
Byrne maintains a philosophical view regarding the potential for limited discoveries. Understanding why one ocean fails to support life could be as enlightening as finding life within it, expanding our outlook on life throughout the cosmos.
For more information, refer to the publication in Nature Communications [here](https://doi.org/10.1038/s41467-025-67151-3).