Search Publications
The Tides of Titan
Stevenson, David J.; Iess, Luciano; Jacobson, Robert A. +7 more
We have detected in Cassini spacecraft data the signature of the periodic tidal stresses within Titan, driven by the eccentricity (e = 0.028) of its 16-day orbit around Saturn. Precise measurements of the acceleration of Cassini during six close flybys between 2006 and 2011 have revealed that Titan responds to the variable tidal field exerted by S…
Strong Tidal Dissipation in Saturn and Constraints on Enceladus' Thermal State from Astrometry
Charnoz, Sébastien; Mathis, Stéphane; Tobie, Gabriel +8 more
Tidal interactions between Saturn and its satellites play a crucial role in both the orbital migration of the satellites and the heating of their interiors. Therefore, constraining the tidal dissipation of Saturn (here the ratio k 2/Q) opens the door to the past evolution of the whole system. If Saturn's tidal ratio can be determined at…
The surface composition of Iapetus: Mapping results from Cassini VIMS
Nicholson, Philip D.; Baines, Kevin H.; Buratti, Bonnie J. +11 more
Cassini VIMS has obtained spatially resolved imaging spectroscopy data on numerous satellites of Saturn. A very close fly-by of Iapetus on September 10, 2007 provided the best data on the spectral signature and spatial extent of dark material on Iapetus. This Cassini Rev 49 Iapetus fly-by provided spatially resolved imaging spectroscopy data of th…
Titan global climate model: A new 3-dimensional version of the IPSL Titan GCM
Charnay, Benjamin; Lebonnois, Sébastien; Rannou, Pascal +1 more
We have developed a new 3-dimensional climate model for Titan’s atmosphere, using the physics of the IPSL Titan 2-dimensional climate model with the current version of the LMDZ General Circulation Model dynamical core. Microphysics and photochemistry are still computed as zonal averages. This GCM covers altitudes from surface to 500 km altitude, w…
Polar methane accumulation and rainstorms on Titan from simulations of the methane cycle
Brown, M. E.; Schaller, E. L.; Schneider, T. +1 more
Titan has a methane cycle akin to Earth's water cycle. It has lakes in polar regions, preferentially in the north; dry low latitudes with fluvial features and occasional rainstorms; and tropospheric clouds mainly (so far) in southern middle latitudes and polar regions. Previous models have explained the low-latitude dryness as a result of atmosphe…
Saturn's icy satellites and rings investigated by Cassini-VIMS: III - Radial compositional variability
Brown, R. H.; Baines, K. H.; Buratti, B. J. +16 more
In the last few years Cassini-VIMS, the Visible and Infrared Mapping Spectrometer, returned to us a comprehensive view of the Saturn's icy satellites and rings. After having analyzed the satellites' spectral properties (Filacchione, G., Capaccioni, F., McCord, T.B., Coradini, A., Cerroni, P., Bellucci, G., Tosi, F., D'Aversa, E., Formisano, V., Br…
Magnetospheric configuration and dynamics of Saturn's magnetosphere: A global MHD simulation
Hansen, Kenneth C.; Gombosi, Tamas I.; Kivelson, Margaret G. +4 more
We investigate the solar wind interaction with Saturn's magnetosphere by using a global magnetohydrodynamic simulation driven by an idealized time-varying solar wind input that includes features of Corotating Interaction Regions typically seen at Saturn. Our model results indicate that the compressibility of Saturn's magnetosphere is intermediate …
The importance of plasma β conditions for magnetic reconnection at Saturn's magnetopause
Coates, A. J.; Russell, C. T.; Dougherty, M. K. +7 more
Magnetic reconnection is an important process that occurs at the magnetopause boundary of Earth's magnetosphere because it leads to transport of solar wind energy into the system, driving magnetospheric dynamics. However, the nature of magnetopause reconnection in the case of Saturn's magnetosphere is unclear. Based on a combination of Cassini spa…
Enceladus' extreme heat flux as revealed by its relaxed craters
Singer, Kelsi N.; Schenk, Paul M.; McKinnon, William B. +1 more
Enceladus' cratered terrains contain large numbers of unusually shallow craters consistent with deformation by viscous relaxation of water ice under conditions of elevated heat flow. Here we use high-resolution topography to measure the relaxation fraction of craters on Enceladus far from the active South Pole. We find that many craters are shallo…
On the Migration of Jupiter and Saturn: Constraints from Linear Models of Secular Resonant Coupling with the Terrestrial Planets
Lin, D. N. C.; Agnor, Craig B.
We examine how the late divergent migration of Jupiter and Saturn may have perturbed the terrestrial planets. Using a modified secular model we have identified six secular resonances between the ν5 frequency of Jupiter and Saturn and the four apsidal eigenfrequencies of the terrestrial planets (g 1-4). We derive analytic uppe…