Ongoing hydrothermal activities within Enceladus

  title={Ongoing hydrothermal activities within Enceladus},
  author={Hsiang-Wen Hsu and Frank Postberg and Yasuhito Sekine and Takazo Shibuya and Sascha Kempf and Mih{\'a}ly Hor{\'a}nyi and Antal Juh{\'a}sz and Nico Altobelli and Katsuhiko Suzuki and Yuka Masaki and Tatsu Kuwatani and Shogo Tachibana and Sin-iti Sirono and Georg Moragas-Klostermeyer and Ralf Srama},
Detection of sodium-salt-rich ice grains emitted from the plume of the Saturnian moon Enceladus suggests that the grains formed as frozen droplets from a liquid water reservoir that is, or has been, in contact with rock. Gravitational field measurements suggest a regional south polar subsurface ocean of about 10 kilometres thickness located beneath an ice crust 30 to 40 kilometres thick. These findings imply rock–water interactions in regions surrounding the core of Enceladus. The resulting… 
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.
Planetary science: Enceladus' hot springs
Silica grains interpreted as silica grains that were initially embedded in the icy plume emitted from subsurface waters on Enceladus and released by sputter erosion in Saturn's E ring are interpreted.
Macromolecular organic compounds from the depths of Enceladus
The detection of complex organic molecules with masses higher than 200 atomic mass units in ice grains emitted from Enceladus indicates the presence of a thin organic-rich layer on top of the moon’s subsurface ocean.
Enceladus: Evidence and Unsolved Questions for an Ice-Covered Habitable World
The icy midsized satellite of Saturn—Enceladus—has become the central to astrobiology since the finding of its dramatic ongoing geological activity. The water-rich plumes erupting from the warm
Organic compounds in ice grains from the subsurface ocean of Enceladus
Cassini’s on board mass spectrometers – the Ion and Neutral Mass Spectrometer (INMS) [1] and the Cosmic Dust Analyzer (CDA) [2] – have measured the plume of gas and ice grains ejected from Enceladus’
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
Analogue experiments for the detection of microorganisms on Enceladus and Europa
From its south pole, the Saturnian moon Enceladus ejects plumes of gas and water ice grains, formed from its subsurface ocean, into space. A similar phenomenon is suspected to occur on Jupiter’s moon
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.
Low-mass nitrogen-, oxygen-bearing, and aromatic compounds in Enceladean ice grains
Saturn’s moon Enceladus is erupting a plume of gas and ice grains from its south pole. Linked directly to the moon’s subsurface global ocean, plume material travels through cracks in the icy crust
Sampling Plume Deposits on Enceladus’ Surface to Explore Ocean Materials and Search for Traces of Life or Biosignatures
Enceladus is unique as an astrobiology target in that it hosts an active plume sourced directly from its habitable subsurface ocean. Ice particles from the plume contain geochemical constituents that


Sodium salts in E-ring ice grains from an ocean below the surface of Enceladus
The identification of a population of E-ring grains that are rich in sodium salts, which can arise only if the plumes originate from liquid water, and the abundance of various salt components in these particles exhibit a compelling similarity to the predicted composition of a subsurface Enceladus ocean in contact with its rock core.
A salt-water reservoir as the source of a compositionally stratified plume on Enceladus
Whereas previous Cassini observations were compatible with a variety of plume formation mechanisms, these data eliminate or severely constrain non-liquid models and strongly imply that a salt-water reservoir with a large evaporating surface provides nearly all of the matter in the plume.
Slow dust in Enceladus' plume from condensation and wall collisions in tiger stripe fractures
It is shown that repeated wall collisions of grains, with re-acceleration by the gas, induce an effective friction, offering a natural explanation for the reduced grain velocity, and suggests liquid water below Enceladus’ south pole.
Hydrothermal systems in small ocean planets.
It is shown that the time-varying hydrostatic head of a tidally forced ice shell may drive hydrothermal fluid flow through the seafloor, which can generate moderate but potentially important heat through viscous interaction with the matrix of porous seafl floor rock.
Differentiation of silicates from H2O ice in an icy body induced by ripening
One of the probable scenarios of differentiation between silicate-ice in an icy object is the settling of a silicate particle in water after the melting of the object. In order for settling to
The Gravity Field and Interior Structure of Enceladus
The quadrupole gravity field of Enceladus and its hemispherical asymmetry is determined using Doppler data from three spacecraft flybys to indicate the presence of a negative mass anomaly in the south-polar region, largely compensated by a positive subsurface anomaly compatible with the existence of a regional subsurfaced sea at depths of 30 to 40 kilometers.