Ulteriori informazioni
Recent space missions to the outer solar system, Galileo (1996-2003) and Cassini-Huygens (2004-today), together with ground observations, have revealed that the moons of the outer solar system are enigmatic objects, introducing extraordinary challenges for geologists, astrobiologists, organic chemists, and planetologists. Chemical exchange exists through the different layers that form their interiors, and also from the interior to the surface. The most convincing evidence is certainly the discovery of water vapour and ice particles emerging from Enceladus's active south polar region. Evidence for exchange with a subsurface liquid ocean has also been provided by the inference of hydrated salts on the surfacesof Jupiter's moons, Europa and Ganymede, as well as the detection of sodium salts in particles originating in Enceladus's plumes. Aqueous exchange with the rocky core may also be possible, considering that 40Ar has been observed in the plumes of Enceladus during one flyby of Cassini and in the atmosphere of Titan. The ongoing CH4 replenishment in Titan's atmosphere is additional striking evidence of exchange processes within the moons.
Sommario
Foreword.- Preface.- Environments in the Outer Solar System.- Characteristics of Icy Surfaces.- Chemical Composition of Icy Satellite Surfaces.- Atmospheric/Exospheric Characteristics of Icy Satellites.- Phase Behaviour of Ices and Hydrates.- Spectroscopy of Icy Moon Surface Materials.- Radar Signal Propagation and Detection Through Ice.- Rheological and Thermal Properties of Icy Materials.- Radiolysis and Photolysis of Icy Satellite Surfaces: Experiments and Theory.- Implications of Rotation, Orbital States, Energy Sources, and Heat Transport for Internal Processes in Icy Satellites.- Effects of the External Environment on Icy Satellites.- Surface, Subsurface and Atmosphere Exchanges on the Satellites of the Outer Solar System.- From Gas to Satellitesimals: Disk Formation and Evolution.- Planetesimals and Satellitesimals: Formation of the Satellite Systems.- Evolution of Icy Satellites.- Subsurface Water Oceans on Icy Satellites: Chemical Composition and Exchange Processes.- Exobiology and Planetary Protection of icy moons.
Riassunto
Recent space missions to the outer solar system, Galileo (1996–2003) and Cassini-Huygens (2004–today), together with ground observations, have revealed that the moons of the outer solar system are enigmatic objects, introducing extraordinary challenges for geologists, astrobiologists, organic chemists, and planetologists. Chemical exchange exists through the different layers that form their interiors, and also from the interior to the surface. The most convincing evidence is certainly the discovery of water vapour and ice particles emerging from Enceladus’s active south polar region. Evidence for exchange with a subsurface liquid ocean has also been provided by the inference of hydrated salts on the surfaces
of Jupiter’s moons, Europa and Ganymede, as well as the detection of sodium salts in particles originating in Enceladus’s plumes. Aqueous exchange with the rocky core may also be possible, considering that 40Ar has been observed in the plumes of Enceladus during one flyby of Cassini and in the atmosphere of Titan. The ongoing CH4 replenishment in Titan’s atmosphere is additional striking evidence of exchange processes within the moons.
