Radar-Bright Valley (Titan)
Résumé
Fluvial valleys on Titan have diverse morphologies with subclasses as defined by arid but cold climatic conditions. Dry valleys with lengths <300 km and width <8 km are observed. They appear radar-bright on Cassini SAR images because they are not filled with liquid but with sediments that are probably centimetric or even larger in size in the brightest valleys. They are similar to terrestrial desert washes (wadis), which suggests formation by sudden, episodic, and strong flow events in dry climatic conditions, followed by long dry periods. Outflow events may be induced by precipitation or sapping. Compared to valleys within integrated dendritic networks, Titan’s dry valleys are generally shorter and broader (Porco et al. 2005; Elachi et ...