Hydrated Salt Minerals on Ganymede's Surface: Evidence of an Ocean Below

@article{McCord2001HydratedSM,
  title={Hydrated Salt Minerals on Ganymede's Surface: Evidence of an Ocean Below},
  author={Thomas B. McCord and Gary B. Hansen and Charles Hibbitts},
  journal={Science},
  year={2001},
  volume={292},
  pages={1523 - 1525}
}
Reflectance spectra from Galileo's near-infrared mapping spectrometer (NIMS) suggests that the surface of Ganymede, the largest satellite of Jupiter, contains hydrated materials. These materials are interpreted to be similar to those found on Europa, that is, mostly frozen magnesium sulfate brines that are derived from a subsurface briny layer of fluid. 
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References

SHOWING 1-10 OF 12 REFERENCES
Salts on Europa's surface detected by Galileo's near infrared mapping spectrometer. The NIMS Team.
TLDR
Reflectance spectra obtained by Galileo's Near Infrared Mapping Spectrometer exhibit distorted water absorption bands that indicate the presence of hydrated minerals, and may represent evaporite deposits formed by water, rich in dissolved salts, reaching the surface from a water-rich layer underlying an ice crust. Expand
Sulfuric acid on Europa and the radiolytic sulfur cycle.
TLDR
A comparison of laboratory spectra with Galileo data indicates that hydrated sulfuric acid is present and is a major component of Europa's surface, and this moon's visually dark surface material is identified as radiolytically altered sulfur polymers. Expand
Thermal segregation of water ice on the Galilean satellites
Abstract Consideration of the thermal sublimation of ice on the Galilean satellites suggests that dirty-ice surfaces are susceptible to a process of cold-trapping of water in local bright patches andExpand
Non‐water‐ice constituents in the surface material of the icy Galilean satellites from the Galileo near‐infrared mapping spectrometer investigation
We present evidence for several non-ice constituents in the surface material of the icy Galilean satellites, using the reflectance spectra returned by the Galileo near infrared mapping spectrometerExpand
Brine volcanism and the interior structures of asteroids and icy satellites
Abstract Cryovolcanism is among the foremost processes responsible for modifying the surfaces of icy satellites. Volcanic brine petrogenesis in ammonia-deficient satellites should mainly involveExpand
Thermal and radiation stability of the hydrated salt minerals epsomite, mirabilite, and natron under Europa environmental conditions
We report studies on the thermal and radiolytic stability of the hydrated salt minerals epsomite (MgSO4·7H2O), mirabilite (Na2SO4·10H2O), and natron (Na2CO3·10H2O) under the low-temperature andExpand
The water regime of asteroid (1) Ceres
Abstract An analytical model is presented which describes the water regime of asteroid Ceres. The model predicts surface and subsurface temperatures, water fluxes, and ice depths as well asExpand
Galilean Satellites: Identification of Water Frost
TLDR
The leading side of JIII has 20 percent more frost cover than the trailing side, which explains the visible geometric albedo differences between the two sides, and the reflectivity of the material underlying the frost on JII, JIII, and JIV resembles that of silicates. Expand
Europa's differentiated internal structure: inferences from two Galileo encounters.
TLDR
Doppler data generated with the Galileo spacecraft's radio carrier wave during two Europa encounters were used to measure Europa's external gravitational field and indicate that Europa has a predominantly water ice-liquid outer shell and a deep interior with a density in excess of about 4000 kilograms per cubic meter. Expand
Spectra of the icy Galilean satellites from 0.2 to 5μm: A compilation, new observations, and a recent summary
From a variety of sources in the literature and from recent, unpublished, high-spectral-resolution data, we can now piece together spectra of both leading and trailing hemispheres for all three icyExpand
...
1
2
...