HR: 1340h
AN: P23B-1354    [Abstracts]
TI: Photoclinometry, Morphometry, and Spectroscopy of Titan's Sand Dunes from Cassini/VIMS
AU: * Barnes, J W
EM: jason@barnesos.net
AF: NASA Ames, NASA Ames Research Center M/S 244-30, Moffett Field, CA 94035, United States
AU: Brown, R H
EM: rhb@lpl.arizona.edu
AF: LPL, University of Arizona 1629 E University Blvd, Tucson, AZ 85721, United States
AU: Soderblom, L A
EM: lsoderblom@usgs.gov
AF: USGS, United States Geological Survey, Flagstaff, AZ 85001, United States
AU: Sotin, C
EM: Christophe.Sotin@jpl.nasa.gov
AF: JPL, Jet Propulsion Laboratory Caltech 4800 Oak Grove Drive, Pasadena, CA 91009, United States
AU: Jaumann, R
EM: ralf.jaumann@dlr.de
AF: DLR, DLR Institute for Planetary Research Rutherfordstrasse 2, Berlin, D-12489, Germany
AU: LeMouelic, S
EM: stephane.lemouelic@univ-nantes.fr
AF: Universite de Nantes, Laboratoire de Planetologie et Geodynamique UMR CNRS Universite de Nantes, Nantes, 44072, France
AU: Rodriguez, S
EM: Sebastien.Rodriguez@univ-nantes.fr
AF: Laboratoire AIM, Laboratoire AIM Centre d'etude de Saclay DAPNIA/Sap Centre de l'Orme des Merisiers, Gif/Yvette, 91191, France
AU: Beyer, R A
EM: Ross.A.Beyer@nasa.gov
AF: NASA Ames, NASA Ames Research Center M/S 244-30, Moffett Field, CA 94035, United States
AU: Beyer, R A
EM: Ross.A.Beyer@nasa.gov
AF: SETI, Carl Sagan Center SETI Institute, Mountain View, CA 94043, United States
AU: Buratti, B J
EM: bburatti@scn.jpl.nasa.gov
AF: JPL, Jet Propulsion Laboratory Caltech 4800 Oak Grove Drive, Pasadena, CA 91009, United States
AU: Pitman, K
EM: Karly.M.Pitman@jpl.nasa.gov
AF: JPL, Jet Propulsion Laboratory Caltech 4800 Oak Grove Drive, Pasadena, CA 91009, United States
AU: Baines, K H
EM: blueskies4321@yahoo.com
AF: JPL, Jet Propulsion Laboratory Caltech 4800 Oak Grove Drive, Pasadena, CA 91009, United States
AU: Nicholson, P D
EM: nicholson@astrosun.tn.cornell.edu
AF: JPL, Jet Propulsion Laboratory Caltech 4800 Oak Grove Drive, Pasadena, CA 91009, United States
AU: Nicholson, P D
EM: nicholson@astrosun.tn.cornell.edu
AF: Cornell, Cornell University Astronomy Department, Ithaca, NY 14853, United States
AB: We present results from recent Cassini Visual and Infrared Mapping Spectrometer (VIMS) observations of the sand seas that cover Titan's equatorial region. High-resolution (~500 m/pixel) spectral mapping from the T20 Titan flyby on 2006 October 20 shows the dunes. The dunes themselves, and presumably therefore the sand of which they are comprised, are dark in all of Titan's spectral windows. The spectrum best matches organic material, but a small water-ice component cannot be ruled out. Thus the sand particles cannot be pure water ice but could still be mostly ice by volume but coated by an organic rind at least several microns thick. The dunes are separated by interdunes in some places, but are continuous in others. Where interdunes exist, we are able to map the extent of the substrate units. Where no interdunes exist, we use photoclinometry to ascertain crest-trough-crest heights of between 30 and 70 meters. Dune separations in the T20 observations are just over 2 kilometers from crest to crest; the dunes' orientations are predominantly east-west, but with variations of up to 10 degrees in either direction. A properly designed future VIMS observation would be capable of gathering a resolved profile of the dune slopes to ascertain wind direction and present activity status.
DE: 6281 Titan
SC: Planetary Sciences [P]
MN: 2007 Fall Meeting