P12B-02
Liquid-Filled Channels On Titan
Monday, 14 December 2015: 10:35
2007 (Moscone West)
Valerio Poggiali1, Marco Mastrogiuseppe2, Alexander Hayes3, Roberto Seu4, Samuel P Birch3, Jason Daniel Hofgartner5, Enrico Flamini6, Ralph D Lorenz7, Cyril Grima8, Jeffrey S Kargel9 and Joseph Mullen3, (1)Sapienza University of Rome, Rome, Italy, (2)Cornell University, Astronomy, Ithaca, NY, United States, (3)Cornell University, Department of Astronomy, Ithaca, NY, United States, (4)Università La Sapienza, Dipartimento di Ingegneria dell’Informazione, Rome, Italy, (5)Cornell University, Ithaca, NY, United States, (6)Italian Space Agency, Rome, Italy, (7)Applied Physics Laboratory Johns Hopkins, Laurel, MD, United States, (8)University of Texas, Institute for Geophysics, Austin, TX, United States, (9)University of Arizona, Tucson, AZ, United States
Abstract:
Saturn’s largest moon, Titan, has an active methane-based hydrologic cycle that drives processes and formation of landforms bearing striking similarities to hydrogeologic and meteorological processes and features on Earth. During a close flyby (~1400 km) in May 2013, Cassini’s RADAR instrument observed the hydrocarbon sea Ligeia Mare using its altimetry mode. In addition to observing the sea, these observations also covered a sequence of channels pertaining to the Vid Flumina drainage basin. While radar images have been used to identify fluvial valleys in networks that extend for hundreds of kilometers, these images do not directly probe the existence or extent of any liquid-filled channels in the valleys. Herein, we use the Cassini altimetry over Vid Flumina to, for the first time, directly detect the presence of liquid-filled channels on Titan and characterize their width and geomorphologic context. Our discovery confirms that Titan does indeed have liquid filled channels in the present epoch. Steep-sided channels extend hundreds of meters below the surrounding terrain and in some cases exhibit canyon morphology. Liquid elevations in Vid Flumina and its lower tributaries are at the same level of Ligeia Mare to within the instrument vertical accuracy (~15m). We also find higher order tributaries that occur several hundred meters above the level of Ligeia Mare, consistent with drainage feeding into the main channel system.
