1 1 2.6 Physical Chemistry and Thermal Evolution of Ices at Ganymede 2 C. Ahrens, NASA Goddard Space Flight Center, Greenbelt, MD;
[email protected] 3 A. Solomonidou, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA; & LEISA 4 – Observatoire de Paris, CNRS, UPMC Univ., Paris 06, Univ. Paris-Diderot, Meudon, France; 5
[email protected] 6 K. Stephan, Institute of Planetary Research, German Aerospace Center (DLR), Berlin, Germany; 7
[email protected] 8 K. Kalousova, Charles University, Faculty of Mathematics and Physics, Department of Geophysics, 9 Prague, Czech Republic;
[email protected] 10 N. Ligier, Institut d’Astrophysique Spatiale, Université Paris-Saclay, Orsay, France; 11
[email protected] 12 T. McCord, Bear Fight Institute, Winthrop, WA;
[email protected] 13 C. Hibbitts, Applied Physics Laboratory, Johns Hopkins University, Laurel, MD; 14
[email protected] 15 16 Abstract 17 18 Ganymede’s surface is composed mostly of water ice and other icy materials in addition to minor non-ice 19 components. The formation and evolution of Ganymede’s landforms highly depend on the nature of the 20 icy materials as they present various thermal and rheological behaviors. This chapter reviews the 21 currently known thermodynamic parameters of the ice phases and hydrates reported on Ganymede, which 22 seem to affect the evolution of the surface, using mainly results from the Voyager and Galileo missions. 23 24 Keywords: Ganymede; Ices; Ices, Mechanical Properties; Experimental techniques; Geological 25 processes 26 27 1 Introduction 28 29 Icy bodies of the outer solar system, including satellites of the gas giants, harbor surface ices made of 30 volatile molecules, clathrates, and complex molecules like hydrocarbons.