Post contributed by Dr. Mafalda Ianiri, University G. d’Annunzio Chieti- Pescara, International Research School of Planetary Sciences.
The icy surface of Ganymede, the largest satellite of the Jupiter system, presents two dominant terrains characterized by different albedo: the dark and light terrains (Image 1). The dark terrains are composed of dark, albedo-heterogeneous material, modified by surficial processes, such as sublimation, mass wasting, and sputtering (ejection and redistribution of molecules across the Ganymede’s surface, which is caused by the energy transferred to the surface through the impact of particles from Jupiter’s magnetosphere; Pappalardo et al., 2004). The dark terrains are highly cratered, preserving the relicts of vast global-scale sets of concentrically arranged structures, called furrows (Pappalardo et al., 2004). The younger light terrains are more extensive than the dark terrains, covering approximately 64% of Ganymede’s surface (Patterson et al., 2010). Light terrains are pervasively crossed by sets of sub-parallel, closely spaced ridges and troughs, referred to as grooves (Patterson et al., 2010; Pappalardo et al., 2004).
Image 1: Geomorphological map of Anshar Sulcus region of Ganymede based on the 2865_r and 2878_r high resolution images captured by Galileo SSI camera. (Credit: Ianiri et al., 2023).
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Planetary Geomorphology Image of the Month 