NASA's Cassini Data Reveals Enceladus' Hidden Ocean

NASA's recent findings from the Cassini mission have provided groundbreaking insights into Enceladus, one of Saturn's moons. Supercomputer simulations conducted by the Texas Advanced Computing Center have refined previous estimates of how much ice Enceladus loses to space.

The mass flow rates identified are between 20 to 40 percent lower than previously reported in scientific literature, according to Arnaud Mahieux, a senior researcher at the Royal Belgian Institute for Space Aeronomy.

In a study published in August 2025 in the Journal of Geophysical Research: Planets, Mahieux and his team utilized Direct Simulation Monte Carlo models to effectively characterize the enormous plumes of water vapor and icy grains that erupt from the moon's surface.

These simulations build on prior research that applied similar methods to deduce conditions around the plumes, including vent size and the ratio of water vapor to ice grains. The team has achieved a significant advancement in understanding Enceladus's cryovolcanic activity.

They were able to derive parameters such as the temperature of the material exiting the plumes and the mass flow rates from a hundred cryovolcanic sources. Enceladus spans just 313 miles across and its weak gravity cannot fully retain the ejecta from its icy jets.

The DSMC models account for this unique dynamic. The simulations track gas behavior at the microscopic level, allowing researchers to simulate millions of molecules over microsecond time steps. This approach has enabled calculations at more realistic pressures than before, providing deeper insights into the moon's plume dynamics.

As Enceladus resides beyond the solar system's snow line, it, along with other icy moons of giant planets, may harbor subsurface oceans. Mahieux noted that there exists a liquid ocean beneath these icy bodies, suggesting that other worlds besides Earth could potentially support life.

Future missions, being planned by NASA and the European Space Agency, aim to revisit Enceladus with more than just flybys. These missions could involve landing on the moon's surface and drilling through its icy crust to sample the underlying ocean.

By analyzing plume materials, scientists hope to assess subsurface conditions and search for signs of life without penetrating deep into the crust. Mahieux emphasized the transformative power of supercomputers in advancing our understanding of such complex systems, enabling scientists to simulate processes they could not have imagined a decade ago.