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Valley formation and methane precipitation rates on Titan
Perron, J. Taylor; Lamb, Michael P.; Koven, Charles D. +3 more
Branching valley networks near the landing site of the Huygens probe on Titan imply that fluid has eroded the surface. The fluid was most likely methane, which forms several percent of Titan's atmosphere and can exist as a liquid at the surface. The morphology of the valley networks and the nature of Titan's surface environment are inconsistent wi…
Cassini imaging of Saturn: Southern hemisphere winds and vortices
West, R. A.; Kennedy, M. R.; Porco, C. C. +4 more
High-resolution images of Saturn's southern hemisphere acquired by the Cassini Imaging Science Subsystem between February and October 2004 are used to create maps of cloud morphology at several wavelengths, to derive zonal winds, and to characterize the distribution, frequency, size, morphology, color, behavior, and lifetime of vortices. Nonequato…
Vertical wind shear on Jupiter from Cassini images
West, Robert A.; Porco, Carolyn C.; Ingersoll, Andrew P. +5 more
Multifilter images of Jupiter acquired by the Cassini Imaging Science Subsystem (ISS) are used to derive zonal winds at altitudes above and below the visible cloud deck. Small features unique to the ultraviolet images of ISS are tracked to get the systematic high-altitude zonal winds. Comparison between the zonal winds from ultraviolet images and …
Enhanced transport in the polar mesosphere of Jupiter: Evidence from Cassini UVIS helium 584 Å airglow
Parkinson, C. D.; Stewart, A. I. F.; Wong, A. S. +2 more
The eddy diffusion profile (K) in the auroral regions of Jupiter is not well determined. However, because of the intense auroral energy input, eddy mixing is expected to be much more effective and may be responsible for the enhancement of heavy hydrocarbon production in the polar region. In this paper, we estimate the increased eddy mixing in the …
Internal structure of Rhea
Castillo-Rogez, Julie
We model the interior of Rhea on the basis of observational constraints and the results from geodynamical models available in the literature. Ten main types of models are defined, depending on the presence or absence of a high-pressure ice layer (ice II), and the extent of separation of the rock component from the volatiles. The degree-two gravity…
Models of synthetic aperture radar backscattering for bright flows and dark spots on Titan
Paillou, Philippe; Crapeau, Marc; Elachi, Charles +2 more
The synthetic aperture radar (SAR) imaging mode of the Cassini RADAR instrument enables us to map the surface of Titan through its thick atmosphere. The first Cassini close flyby, acquired on 26 October 2004, revealed a complex surface, with areas of low relief and dome-like volcanic constructs, flows, and sinuous channels. In particular, fan-like…
Bistatic observations of Titan's surface with the Huygens probe radio signal
Lorenz, R. D.; Lebreton, J. -P.; Floury, N. +2 more
Huygens provided an unanticipated bistatic radio scattering experiment from Titan's surface. After a successful entry and descent on Titan, on 14 January 2005, the probe remarkably survived the landing and continued radioing from the surface to the overflying Cassini, until the orbiter set below Titan's local horizon. Here we report high-quality m…
High-resolution infrared spectroscopy of ethane in Titan's stratosphere in the Huygens epoch
Sonnabend, G.; Kostiuk, T.; Schieder, R. +7 more
High-resolution infrared spectroscopy of ethane (C2H6) emission features formed in the stratosphere of Titan was collected on disc center at 11.74 µm wavelength (851 cm-1) on 15 January 2005 UT. The observations were obtained at the Subaru 8.2 m telescope of the National Astronomical Observatory of Japan on M…
Huygens entry emission: Observation campaign, results, and lessons learned
de Pater, Imke; Lorenz, Ralph D.; Lemmon, Mark T. +8 more
An attempt was made to observe from Earth the emission from the shock layer and ``meteor trail'' formed during the Huygens probe's hypersonic entry into Titan's atmosphere. Although many observations were wiped out by weather or in-orbit failure, two observations constrain the emission from the entry. Several important lessons for future observati…