Cassini finds molecular hydrogen in the Enceladus plume: Evidence for hydrothermal processes

• DOI: 10.1126/science.aai8703
• Publication Date: 2017-04-13T17:55:16Z
• Authors: J. Hunter Waite; Christopher R. Glein; Rebecca S. Perryman; Ben D. Teolis; Brian A. Magee; Greg Miller; Jacob Grimes; Mark E. Perry; Kelly E. Miller; Alexis Bouquet; Jonathan I. Lunine; Tim Brockwell; Scott J. Bolton
• Keywords: Enceladus; Hydrogen molecule

Saturn's moon Enceladus has an ice-covered ocean; a plume of material erupts from cracks in the ice. The contains chemical signatures water-rock interaction between ocean and rocky core. We used Ion Neutral Mass Spectrometer onboard Cassini spacecraft to detect molecular hydrogen plume. By using instrument's open-source mode, background processes production instrument were minimized quantified, enabling identification statistically significant signal native Enceladus. find that most plausible source this is ongoing hydrothermal reactions rock containing reduced minerals organic materials. relatively high abundance signals thermodynamic disequilibrium favors formation methane CO2 Enceladus' ocean.