Search Publications
Channel morphometry, sediment transport, and implications for tectonic activity and surficial ages of Titan basins
Kirk, Randolph L.; Cartwright, Richard; Clayton, Jordan A.
Fluvial features on Titan and drainage basins on Earth are remarkably similar despite differences in gravity and surface composition. We determined network bifurcation ( R b) ratios for five Titan and three terrestrial analog basins. Tectonically-modified Earth basins have R b values greater than the expected range (3.0-5.0) …
Analytical description of physical librations of saturnian coorbital satellites Janus and Epimetheus
Robutel, Philippe; Rambaux, Nicolas; Castillo-Rogez, Julie
Janus and Epimetheus are famously known for their distinctive horseshoe-shaped orbits resulting from a 1:1 orbital resonance. Every 4 years these two satellites swap their orbits by a few tens of kilometers as a result of their close encounter. Recently Tiscareno et al. (Tiscareno, M.S., Thomas, P.C., Burns, J.A. [2009]. Icarus 204, 254-261) have …
Secondary chaotic terrain formation in the higher outflow channels of southern circum-Chryse, Mars
Fairén, Alberto G.; Kargel, Jeffrey S.; Baker, Victor R. +7 more
Higher outflow channel dissection in the martian region of southern circum-Chryse appears to have extended from the Late Hesperian to the Middle Amazonian Epoch. These outflow channels were excavated within the upper 1 km of the cryolithosphere, where no liquid water is expected to have existed during these geologic epochs. In accordance with prev…
Large asymmetric polar scarps on Planum Australe, Mars: Characterization and evolution
Kofman, Wlodek; Herique, Alain; Grima, Cyril +6 more
Numerous scarps with similar characteristics have been observed in the polar layered deposits of Planum Australe, Mars. They are referred to as LAPSs (for Large Asymmetric Polar Scarps) because of their typical cross-section featuring a trough between a straight slope on one side with outcrops of layered deposits and a convex slope on the other si…
Preservation of layered paleodeposits in high-latitude pedestal craters on Mars
Head, James W.; Kadish, Seth J.
An outstanding question in Mars' climate history is whether or not pedestal craters represent the armored remnants of ice-rich paleodeposits. We address this question using new high-resolution images; in a survey of several hundred high-latitude pedestal craters, we have identified 12 examples in which visible and/or topographically expressed laye…
Long slit spectropolarimetry of Jupiter and Saturn
Buenzli, E.; Schmid, H. M.; Gisler, D. +1 more
We present ground-based limb polarization measurements of Jupiter and Saturn consisting of full disk imaging polarimetry for the wavelength 7300 Å and spatially resolved (long-slit) spectropolarimetry covering the wavelength range 5200-9350 Å. For the polar region of Jupiter we find for λ = 6000 Å a very strong radial (perpendicular to the limb) f…
Saturn's F ring grains: Aggregates made of crystalline water ice
Nicholson, Philip D.; Sotin, Christophe; Clark, Roger N. +8 more
We present models of the near-infrared (1-5 µm) spectra of Saturn's F ring obtained by Cassini's Visual and Infrared Mapping Spectrometer (VIMS) at ultra-high phase angles (177.4-178.5°). Modeling this spectrum constrains the size distribution, composition, and structure of F ring particles in the 0.1-100 µm size range. These spectra a…
Emergence of polar-jet polygons from jet instabilities in a Saturn model
Ingersoll, Andrew P.; Dowling, Timothy E.; Sayanagi, Kunio M. +1 more
Voyager flybys of Saturn in 1980-1981 revealed a circumpolar wave at ≈78° north planetographic latitude. The feature had a dominant wavenumber 6 mode, and has been termed the Hexagon from its geometric appearance in polar-projected mosaics. It was also noted for being stationary with respect to Saturn's Kilometric Radiation (SKR) rotation rate. Th…
Hypsometry of Titan
Lorenz, Ralph D.; Turtle, Elizabeth P.; Le Gall, Alice +6 more
Cassini RADAR topography data are used to evaluate Titan's hypsometric profile, and to make comparisons with other planetary bodies. Titan's hypsogram is unimodal and strikingly narrow compared with the terrestrial planets. To investigate topographic extremes, a novel variant on the classic hypsogram is introduced, with a logarithmic abscissa to h…
A bolometric Bond albedo map of Iapetus: Observations from Cassini VIMS and ISS and Voyager ISS
Buratti, Bonnie J.; Blackburn, David G.; Ulrich, Richard
We utilized Cassini VIMS, Cassini ISS, and Voyager ISS observations of Iapetus to produce the first bolometric Bond albedo map of Iapetus. The average albedo values for the leading and trailing hemispheres are 0.06 ± 0.01 and 0.25 ± 0.03, respectively. However, the bright material in high-resolution ISS images has a value of 0.38 ± 0.04, highlight…