Search Publications
Accretion of Saturn’s mid-sized moons during the viscous spreading of young massive rings: Solving the paradox of silicate-poor rings versus silicate-rich moons
Dones, Luke; Charnoz, Sébastien; Crida, Aurélien +7 more
The origin of Saturn’s inner mid-sized moons (Mimas, Enceladus, Tethys, Dione and Rhea) and Saturn’s rings is debated. Charnoz et al. [Charnoz, S., Salmon J., Crida A., 2010. Nature 465, 752-754] introduced the idea that the smallest inner moons could form from the spreading of the rings’ edge while Salmon et al. [Salmon, J., Charnoz, S., Crida, A…
Transient surface liquid in Titan's polar regions from Cassini
Lorenz, R. D.; Wye, L. C.; Zebker, H. A. +12 more
Cassini RADAR images of Titan's south polar region acquired during southern summer contain lake features which disappear between observations. These features show a tenfold increases in backscatter cross-section between images acquired one year apart, which is inconsistent with common scattering models without invoking temporal variability. The mo…
Plasma, plumes and rings: Saturn system dynamics as recorded in global color patterns on its midsize icy satellites
Johnson, Robert E.; Hamilton, Douglas P.; McKinnon, William B. +4 more
New global maps of the five inner midsize icy saturnian satellites, Mimas, Enceladus, Tethys, Dione, and Rhea, have been constructed in three colors (UV, Green and near-IR) at resolutions of 1 km/pixel. The maps reveal prominent global patterns common to several of these satellites but also three major color features unique to specific satellites …
Energy deposition and primary chemical products in Titan’s upper atmosphere
Lewis, G. R.; Coates, A. J.; Galand, M. +4 more
Cassini results indicate that solar photons dominate energy deposition in Titan's upper atmosphere. These dissociate and ionize nitrogen and methane and drive the subsequent complex organic chemistry. The improved constraints on the atmospheric composition from Cassini measurements demand greater precision in the photochemical modeling. Therefore,…
The mesosphere and lower thermosphere of Titan revealed by Cassini/UVIS stellar occultations
Sandel, B. R.; West, R. A.; Yelle, R. V. +5 more
Stellar occultations observed by the Cassini/UVIS instrument provide unique data that probe the mesosphere and lower thermosphere of Titan at altitudes between 400 and 1400 km. This region is a site of complex photochemistry that forms hydrocarbon and nitrile species, and plays a crucial role in the formation of the organic hazes observed in the s…
Organic sedimentary deposits in Titan's dry lakebeds: Probable evaporite
Nicholson, Philip D.; Sotin, Christophe; Barnes, Jason W. +14 more
We report the discovery of organic sedimentary deposits at the bottom of dry lakebeds near Titan's north pole in observations from the Cassini Visual and Infrared Mapping Spectrometer (VIMS). We show evidence that the deposits are evaporitic, making Titan just the third known planetary body with evaporitic processes after Earth and Mars, and is th…
Saturn's zonal wind profile in 2004-2009 from Cassini ISS images and its long-term variability
Hueso, R.; Sánchez-Lavega, A.; García-Melendo, E. +1 more
Five years of Cassini Imaging Science Subsystem images, from 2004 to 2009, are analyzed in this work to retrieve global zonal wind profiles of Saturn's northern and southern hemispheres in the methane absorbing bands at 890 and 727 nm and in their respective adjacent continuum wavelengths of 939 and 752 nm. A complete view of Saturn's global circu…
Titan's aerosol and stratospheric ice opacities between 18 and 500 µm: Vertical and spectral characteristics from Cassini CIRS
Anderson, Carrie M.; Samuelson, Robert E.
Vertical distributions and spectral characteristics of Titan's photochemical aerosol and stratospheric ices are determined between 20 and 560 cm -1 (500-18 µm) from the Cassini Composite Infrared Spectrometer (CIRS). Results are obtained for latitudes of 15°N, 15°S, and 58°S, where accurate temperature profiles can be independentl…
Saturn's tropospheric composition and clouds from Cassini/VIMS 4.6-5.1 µm nightside spectroscopy
Fletcher, Leigh N.; Baines, Kevin H.; Irwin, Patrick G. J. +5 more
The latitudinal variation of Saturn's tropospheric composition (NH 3, PH 3 and AsH 3) and aerosol properties (cloud altitudes and opacities) are derived from Cassini/VIMS 4.6-5.1 µm thermal emission spectroscopy on the planet's nightside (April 22, 2006). The gaseous and aerosol distributions are used to trac…
Temporal variations of Titan’s middle-atmospheric temperatures from 2004 to 2009 observed by Cassini/CIRS
Nixon, Conor A.; Achterberg, Richard K.; Michael Flasar, F. +2 more
We use five and one-half years of limb- and nadir-viewing temperature mapping observations by the Composite Infrared Radiometer-Spectrometer (CIRS) on the Cassini Saturn orbiter, taken between July 2004 and December 2009 ( LS from 293° to 4°; northern mid-winter to just after northern spring equinox), to monitor temperature changes in t…