Mysterious energy source that could fuel life found on Saturn's moon

Enceladus has long fascinated scientists with its mysterious plumes of ice grains and water vapor, which are known to contain organic compounds. However, this latest research goes further by confirming the existence of hydrogen cyanide within these plumes.

In Short

• Enceladus has long fascinated scientists with its mysterious plumes
• The study sheds light on the ocean beneath Enceladus's icy surface
• They were able to discern subtle differences in the plume's composition

Scientists analysing data from NASA's Cassini spacecraft have found compelling evidence of a key ingredient for life on Saturn's icy moon, Enceladus.

The study, published in Nature Astronomy, reveals the presence of hydrogen cyanide, a molecule vital to the origin of life, and a robust source of chemical energy that could potentially sustain life.

Enceladus has long fascinated scientists with its mysterious plumes of ice grains and water vapor, which are known to contain organic compounds. However, this latest research goes further by confirming the existence of hydrogen cyanide within these plumes. This molecule is considered a foundational element for the formation of amino acids, the building blocks of life.

Lead author Jonah Peter, a doctoral student at Harvard University, emphasised the significance of the findings. "Our work provides further evidence that Enceladus is host to some of the most important molecules for both creating the building blocks of life and for sustaining that life through metabolic reactions," he stated.

The study also sheds light on the ocean beneath Enceladus's icy surface, which feeds the plumes and appears to be a powerhouse of chemical energy. Previously unidentified organic compounds were detected, suggesting that Enceladus's subsurface ocean might be more chemically active than previously thought.

Kevin Hand, co-author of the study and a scientist at NASA's Jet Propulsion Laboratory (JPL), likened the energy potential of Enceladus's ocean to a car battery, in contrast to the smaller "watch battery" energy offered by methanogenesis — a process known to produce methane and support life on Earth.

This new research stands apart from previous studies by employing detailed statistical analyses rather than lab experiments or geochemical modeling. The team meticulously examined the data collected by Cassini's ion and neutral mass spectrometer, which analyzed the gas, ions, and ice grains around Saturn.

Through this approach, they were able to discern subtle differences in the plume's composition, strengthening the case for hydrogen cyanide's role.

While the possibility of life originating on Enceladus remains an open question, the study outlines potential chemical pathways that could be explored further in laboratory settings.

The Cassini mission, which concluded in 2017 with the spacecraft's intentional descent into Saturn's atmosphere, continues to yield valuable insights. Tom Nordheim, a JPL planetary scientist and co-author of the study, remarked, "Our study demonstrates that while Cassini's mission has ended, its observations continue to provide us with new insights about Saturn and its moons—including the enigmatic Enceladus."

The research suggests that Enceladus may not only possess the basic requirements for habitability but also offer a chemical environment conducive to the emergence and sustenance of life.

Published By:
Sibu Kumar Tripathi
Published On:
Dec 15, 2023