The sand seas of titan: Cassini RADAR observations of longitudinal dunes

R. D. Lorenz; S. Wall; J. Radebaugh; G. Boubin; E. Reffet; M. Janssen; E. Stofan; R. Lopes; Randolph L. Kirk; C. Elachi; J. Lunine; Ken Mitchell; F. Paganelli; Laurence A. Soderblom; C. Wood; L. Wye; H. Zebker; Y. Anderson; S. Ostro; M. Allison; R. Boehmer; P. Callahan; P. Encrenaz; G.G. Ori; G. Francescetti; Y. Gim; G. Hamilton; S. Hensley; W. Johnson; K. Kelleher; D. Muhleman; G. Picardi; F. Posa; L. Roth; R. Seu; S. Shaffer; B. Stiles; S. Vetrella; E. Flamini; R. West

doi:10.1126/science.1123257

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The sand seas of titan: Cassini RADAR observations of longitudinal dunes

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Abstract

The most recent Cassini RADAR images of Titan show widespread regions (up to 1500 kilometers by 200 kilometers) of near-parallel radar-dark linear features that appear to be seas of longitudinal dunes similar to those seen in the Namib desert on Earth. The Ku-band (2.17-centimeter wavelength) images show ∼100-meter ridges consistent with duneforms and reveal flow interactions with underlying hills. The distribution and orientation of the dunes support a model of fluctuating surface winds of ∼0.5 meter per second resulting from the combination of an eastward flow with a variable tidal wind. The existence of dunes also requires geological processes that create sand-sized (100- to 300-micrometer) particulates and a lack of persistent equatorial surface liquids to act as sand traps.

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R. D. Lorenz, S. Wall, J. Radebaugh, G. Boubin, E. Reffet, M. Janssen, E. Stofan, R. Lopes, Randolph L. Kirk, C. Elachi, J. Lunine, Ken Mitchell, F. Paganelli, Laurence A. Soderblom, C. Wood, L. Wye, H. Zebker, Y. Anderson, S. Ostro, M. Allison, R. Boehmer, P. Callahan, P. Encrenaz, G.G. Ori, G. Francescetti, Y. Gim, G. Hamilton, S. Hensley, W. Johnson, K. Kelleher, D. Muhleman, G. Picardi, F. Posa, L. Roth, R. Seu, S. Shaffer, B. Stiles, S. Vetrella, E. Flamini, R. West. 2006. The sand seas of titan: Cassini RADAR observations of longitudinal dunes. https://doi.org/10.1126/science.1123257

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