NASA Selects Jason Rabinovitch to Lead $767K Study of Eruptions on Enceladus, Saturn’s Frozen Moon

Mechanical Engineering researcher investigates whether the moon's icy volcanic plumes offer insights into its surface - and potential habitability

Are volcanic eruptions on Enceladus, the sixth-largest moon orbiting Saturn, powered by the same forces that make a shaken soda can burst here on Earth? And could these icy volcanic plumes reveal more about the moon's composition - even hinting at the possibility of life?

That's what a team of researchers - led by Jason Rabinovitch, assistant professor in the Stevens Institute of Technology'sDepartment of Mechanical Engineering, and experts from NASA's Jet Propulsion Laboratory (JPL) and Southwest Research Institute (SWRI) - aims to uncover. NASA has granted the team $767,081 to continue its study, "To What Extent Does Enceladus' Plume Sample its Ocean: Insights from Conduit Flow Modeling."

A small moon making big waves

Despite its small size - just 313 miles in diameter - Enceladus has become a major focus for scientists over the past 20 years. That's thanks to NASA's Cassini spacecraft, which discovered the moon's towering geysers shooting water and ice jets into space and creating plumes that contribute to one of Saturn's rings. When Cassini flew through these plumes, it detected water vapor, volatile gasses and organic compounds - some of the essential building blocks for life on Earth.

The prevailing theory for these eruptions suggests that the low pressure in space causes Enceladus' subsurface water to cold boil, releasing water vapor through cracks in its icy surface, much like steam escaping from a cosmic tea kettle.

But Rabinovitch and his team have another beverage-inspired hypothesis in mind - one that's more akin to the explosive release from a shaken soda can.

Jason Rabinovitch, Assistant Professor, Department of Mechanical Engineering

The research team proposes that dissolved gasses, such as methane and hydrogen, could form bubbles as the mixture gets closer to the surface. As the bubbles expand, they could be driving the dramatic volcanic eruptions, much like the pressurized liquid shooting out of a shaken soda can.

Even more intriguing, these gas-driven jets are not composed of just water vapor. The plumes carry materials from the ocean beneath the icy crust, potentially preserving salts, organic molecules and other clues about Enceladus' subsurface ocean.

"Understanding how the plume erupts helps us understand how the composition of the plume relates to the composition of the ocean," Rabinovitch explained. "Sampling these jets could teach us a lot about what's going on beneath the surface of Enceladus."

Indeed, it would mean these eruptions could be carrying salts, organic compounds and other molecules with clues to the moon's composition. Future space missions could bypass the complexity and expense of drilling into the moon's icy surface - opting instead to simply collect viable samples from the plume.

Could there be life on Enceladus?

Through the NASA grant, the research team's goal is to understand how gasses and water travel from the moon's ocean through the ice and into space, and whether the plumes accurately represent what lies beneath the surface.

"Karl Mitchell from JPL is trained in planetary science and volcanology," Rabinovitch said. "His JPL colleagues on the project are Morgan Cable, whose main research interest is chemical signatures of life, and Phillipe Tosi, a mechanical and aerospace engineer. Chris Glein, a geochemist at SWRI, focuses on ocean worlds and chemistry. My expertise is in fluid mechanics. This diverse expertise allowed us to look at both the physics of the plume and the bigger picture of Enceladus' habitability."

As this research progresses, Rabinovitch is eager to see what's next.

"Studying places in our solar system with a lot of water is fascinating," he said. "Studies like these will be vital as we prepare to send future missions to Enceladus. Every time we send a new space mission, we learn new things, and it's humbling and fun and exciting to update the models and deepen our understanding. If we can figure out how these eruptions happen, we'll be better equipped to explore Enceladus and answer the big question: does this icy moon have the right conditions for life?"