Author/Authors :
Lunine، نويسنده , , J.I. and Elachi، نويسنده , , C. and Wall، نويسنده , , S.D. and Janssen، نويسنده , , M.A. and Allison، نويسنده , , M.D. and Anderson، نويسنده , , Y. and Boehmer، نويسنده , , Jonathan R. and Callahan، نويسنده , , P. and Encrenaz، نويسنده , , P. and Flamini، نويسنده , , E. and Franceschetti، نويسنده , , G. and Gim، نويسنده , , Y. and Hamilton، نويسنده , , G. and Hensley، نويسنده , , S. and Johnson، نويسنده , , W.T.K. and Kelleher، نويسنده , , Purnendu K. and Kirk، نويسنده , , R.L. and Lopes، نويسنده , , R.M. and Lorenz، نويسنده , , R. and Muhleman، نويسنده , , D.O. and Orosei، نويسنده , , Pravas R. and Ostro، نويسنده , , S.J. and Paganelli، نويسنده , , F. and Paillou، نويسنده , , P. and Picardi، نويسنده , , G. and Posa، نويسنده , , F. and Radebaugh، نويسنده , , J. and Roth، نويسنده , , L.E. and Seu، نويسنده , , R. and Shaffer، نويسنده , , S. and Soderblom، نويسنده , , L.A. and Stiles، نويسنده , , B. and Stofan، نويسنده , , E.R. and Vetrella، نويسنده , , S. and West، نويسنده , , R. and Wood، نويسنده , , C.A. and Wye، نويسنده , , L. and Zebker، نويسنده , , H. and Alberti، نويسنده , , Irene G. and Karkoschka، نويسنده , , E. and Rizk، نويسنده , , B. and McFarlane، نويسنده , , E. and See، نويسنده , , C. and Kazeminejad، نويسنده , , B.، نويسنده ,
Abstract :
Cassiniʹs third and fourth radar flybys, T7 and T8, covered diverse terrains in the high southern and equatorial latitudes, respectively. The T7 synthetic aperture radar (SAR) swath is somewhat more straightforward to understand in terms of a progressive poleward descent from a high, dissected, and partly hilly terrain down to a low flat plain with embayments and deposits suggestive of the past or even current presence of hydrocarbon liquids. The T8 swath is dominated by dunes likely made of organic solids, but also contain somewhat enigmatic, probably tectonic, features that may be partly buried or degraded by erosion or relaxation in a thin crust. The dark areas in T7 show no dune morphology, unlike the dark areas in T8, but are radiometrically warm like the dunes. The Huygens landing site lies on the edge of the T8 swath; correlation of the radar and Huygens DISR images allows accurate determination of its coordinates, and indicates that to the north of the landing site sit two large longitudinal dunes. Indeed, had the Huygens probe trajectory been just 10 km north of where it actually was, images of large sand dunes would have been returned in place of the fluvially dissected terrain actually seen—illustrating the strong diversity of Titanʹs landscapes even at local scales.
