The sand seas of Titan: Cassini RADAR observations of longitudinal dunes.
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 approximately 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 approximately 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.
Lorenz
R D
RD
Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA. rlorenz@lpl.arizona.edu
Wall
S
S
Radebaugh
J
J
Boubin
G
G
Reffet
E
E
Janssen
M
M
Stofan
E
E
Lopes
R
R
Kirk
R
R
Elachi
C
C
Lunine
J
J
Mitchell
K
K
Paganelli
F
F
Soderblom
L
L
Wood
C
C
Wye
L
L
Zebker
H
H
Anderson
Y
Y
Ostro
S
S
Allison
M
M
Boehmer
R
R
Callahan
P
P
Encrenaz
P
P
Ori
G G
GG
Francescetti
G
G
Gim
Y
Y
Hamilton
G
G
Hensley
S
S
Johnson
W
W
Kelleher
K
K
Muhleman
D
D
Picardi
G
G
Posa
F
F
Roth
L
L
Seu
R
R
Shaffer
S
S
Stiles
B
B
Vetrella
S
S
Flamini
E
E
West
R
R