Bayesian analysis of Enceladus’s plume data to assess methanogenesis

  title={Bayesian analysis of Enceladus’s plume data to assess methanogenesis},
  author={Antonin Affholder and François Guyot and Boris Sauterey and R{\'e}gis Ferri{\`e}re and Stephane Mazevet},
  journal={Nature Astronomy},
Observations from NASA’s Cassini spacecraft established that Saturn’s moon Enceladus has an internal liquid ocean. Analysis of a plume of ocean material ejected into space suggests that alkaline hydrothermal vents are present on Enceladus’s seafloor. On Earth, such deep-sea vents harbour microbial ecosystems rich in methanogenic archaea. Here we use a Bayesian statistical approach to quantify the probability that methanogenesis (biotic methane production) might explain the escape rates of… 
Enceladus as a Potential Niche for Methanogens and Estimation of Its Biomass
Enceladus is a potential target for future astrobiological missions. NASA’s Cassini spacecraft demonstrated that the Saturnian moon harbors a salty ocean beneath its icy crust and the existence and
Theoretical Considerations on the Characteristic Timescales of Hydrogen Generation by Serpentinization Reactions on Enceladus
The Cassini spacecraft demonstrated that Saturn's small moon Enceladus may harbor hydrothermal activity. In particular, molecular hydrogen production could result from water‐rock interactions in a
Survival strategies of an anoxic microbial ecosystem in Lake Untersee, a potential analog for Enceladus
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Instantaneous Habitable Windows in the Parameter Space of Enceladus' Ocean
In recent years, Enceladus' subsurface ocean has become a tantalizing case study for potentially habitable conditions in an extraterrestrial ocean world. However, we still know very little about its
Are microorganisms everywhere they can be?
  • C. Cockell
  • Environmental Science
    Environmental microbiology
  • 2021
Recent evidence is discussed for a diversity of macroscopic habitable environments apparently devoid of actively metabolizing or reproducing life, and these environments have practical uses in being negative controls for understanding the role of microbial processes in geochemical cycles and geological processes.
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The ultimate goal of astrobiology is to determine the distribution and diversity of life in the universe. But as the word “biosignature” suggests, what will be detected is not life itself, but an
Life on Enceladus? It depends on its origin
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Possible evidence for a methane source in Enceladus' ocean
The internal ocean of Enceladus can be expected to present conditions favorable to the trapping of volatiles in clathrates. This process could influence the eventual composition of the ocean and
The pH of Enceladus’ ocean
Cassini finds molecular hydrogen in the Enceladus plume: Evidence for hydrothermal processes
The Ion Neutral Mass Spectrometer onboard the Cassini spacecraft is used to detect molecular hydrogen in the plume of escaping material on Enceladus, finding that the most plausible source of this hydrogen is ongoing hydrothermal reactions of rock containing reduced minerals and organic materials.
The Carbonate Geochemistry of Enceladus' Ocean
The plume composition at Enceladus contains clues about conditions and processes in the interior. We present new geochemical interpretations of Cassini mass spectrometry data from the plume gas and
Biological methane production under putative Enceladus-like conditions
It is shown that a methanogenic archaeon, Methanothermococcus okinawensis, can produce CH4 under physicochemical conditions extrapolated for Saturn’s icy moon, Enceladus, and that serpentinization may produce sufficient H2 for biological methane production.
Powering prolonged hydrothermal activity inside Enceladus
Geophysical data from the Cassini spacecraft imply the presence of a global ocean underneath the ice shell of Enceladus1, only a few kilometres below the surface in the South Polar Terrain2–4.
We describe a formation scenario of Enceladus constrained by the deuterium-to-hydrogen ratio (D/H) in the gas plumes as measured by the Cassini Ion and Neutral Mass Spectrometer. We propose that,
Sea ice, extremophiles and life on extra-terrestrial ocean worlds
Abstract The primary aim of this review is to highlight that sea-ice microbes would be capable of occupying ice-associated biological niches on Europa and Enceladus. These moons are compelling
Ongoing hydrothermal activities within Enceladus
Analysis of silicon-rich, nanometre-sized dust particles (so-called stream particles) that stand out from the water-ice-dominated objects characteristic of Saturn indicate ongoing high-temperature (>90 °C) hydrothermal reactions associated with global-scale geothermal activity that quickly transports hydroThermal products from the ocean floor at a depth of at least 40 kilometres up to the plume of Enceladus.