Composition of the oceans of Jupiter and Saturn's icy moons - Thermodynamic and experimental approaches
type: Dataset
contact point: Organization
  fn: CCSD
keyword: high-pressure-experiment
keyword: clathrate-hydrates
keyword: h2o-co2-system
keyword: theses
keyword: phase-diagram
keyword: extra-terrestrial-ocean
keyword: systeme-h2o-mgso4
keyword: modele-thermodynamique
keyword: hydrates-clathrates
keyword: infoeu-reposemanticsdoctoralthesis
keyword: equilibre-en-systeme-aqueux
keyword: ocean-extra-terrestre
keyword: experience-a-haute-pression
keyword: structure-interne-des-lunes-de-glace
keyword: diagramme-de-phase
keyword: icy-moons-internal-structure
keyword: thermodynamic-model
keyword: h2o-mgso4-system
keyword: equilibria-in-aqueous-systems
keyword: sdustuplsciences-of-the-universe-physicsearth-sciencesplanetology
keyword: systeme-h2o-co2
landing page: https://theses.hal.science/tel-00981491
description: The existence of subsurface aqueous oceans in Jupiter and Saturn's large icy moons, theorized in the 1970s, has been confirmed by data collected by the Voyager, Galileo and Cassini-Huygens missions. The composition of chondritic and cometary materials and the data from these missions suggest that magnesium sulfate and carbon dioxide may be major components of these extra-terrestrial oceans. In order to understand the implications of the presence of these two constituents, new experiments were carried out in the H2O-CO2 and H2O-MgSO4 systems at the high pressures (0 - 2 GPa), low temperatures (250 - 350 K) and compositions (water-rich systems) expected in the hydrospheres of Ganymede, Callisto and Titan. The results from these experiments led to the first global description of the H2O-CO2 system at these conditions. The domain of stability of the two CO2 hydrates and the solubility of CO2 in water at high pressure bring new constraints on the trapping and transfer of this volatile in large icy moons. These data now make possible the high-pressure thermodynamic modeling of the CO2-CH4 sI clathrate hydrate, a phase likely involved in the segregation of these main volatile carbon molecules throughout the hydrospheres of icy moons. The first set of data acquired to constrain the eutectic composition of the H2O-MgSO4 system at high pressures complete available density data and provide the means to understand the evolution of dense oceans within massive hydrospheres. These data support the recent hypothesis of deep oceans at the bottom of the icy mantles of large icy satellites, giving a new perspective on the evolution and dynamics of these bodies.
issued: 2026-05-05T13:51:29.949794
language: fr
modified: 2026-05-05T13:51:29.949800

Composition of the oceans of Jupiter and Saturn's icy moons - Thermodynamic and experimental approaches
type: Distribution
access URL: https://theses.hal.science/tel-00981491
format: HTML
issued: 2026-05-05T13:51:29.955066
modified: 2026-05-05T13:51:29.928608

test_moissonnage_selune
type: Agent