Search Publications
The roles of charge exchange and dissociation in spreading Saturn's neutral clouds
Delamere, P. A.; Bagenal, F.; Fleshman, B. L. +1 more
Neutrals sourced directly from Enceladus's plumes are initially confined to a dense neutral torus in Enceladus's orbit around Saturn. This neutral torus is redistributed by charge exchange, impact/photodissociation, and neutral-neutral collisions to produce Saturn's neutral clouds. Here we consider the former processes in greater detail than in pr…
The CH4 structure in Titan's upper atmosphere revisited
Strobel, D. F.; Galand, M.; Yelle, R. V. +4 more
In this study, we reanalyze the CH4 structure in Titan's upper atmosphere combining the Cassini Ion Neutral Mass Spectrometer (INMS) data from 32 flybys and incorporating several updates in the data reduction algorithms. We argue that based on our current knowledge of eddy mixing and neutral temperature, strong CH4 escape mus…
Analysis of disk-resolved OMEGA and CRISM spectral observations of Phobos and Deimos
Bibring, J. -P.; Arvidson, R. E.; Gondet, B. +8 more
Disk-resolved observations of Phobos acquired by OMEGA at a range of lighting and viewing geometries were fit with the Hapke photometric function to solve for the single particle phase function and single scattering albedos from 0.4 to 2.5 µm. Single scattering albedos were recovered from CRISM observations of Phobos using the OMEGA derived …
Titan's ionospheric composition and structure: Photochemical modeling of Cassini INMS data
Wahlund, J. -E.; Magee, B. A.; Mandt, K. E. +4 more
Titan's upper atmosphere produces an ionosphere at high altitudes from photoionization and electron impact that exhibits complex chemical processes in which hydrocarbons and nitrogen-containing molecules are produced through ion-molecule reactions. The structure and composition of Titan's ionosphere has been extensively investigated by the Ion and…
Estimating erosional exhumation on Titan from drainage network morphology
Black, Benjamin A.; Perron, J. Taylor; Burr, Devon M. +1 more
Drainage networks on Titan, Earth, and Mars provide the only known examples of non-volcanic fluvial activity in our solar system. The drainage networks on Titan are apparently the result of a methane-ethane cycle similar to Earth's water cycle. The scarcity of impact craters and the uneven distribution of fluvial dissection on Titan suggest that t…
Compositional investigation of the proposed chloride-bearing materials on Mars using near-infrared orbital data from OMEGA/MEx
Bibring, Jean-Pierre; Gondet, Brigitte; Poulet, François +7 more
Several hundred occurrences of chloride-bearing salt deposits have been proposed in terrains within the southern highlands of Mars on the basis of Thermal Emission Imaging System and Thermal Emission Spectrometer infrared observations. The spectral identification of chloride salts by remote sensing is challenging because they are transparent over …
First detection of O2 1.27 µm nightglow emission at Mars with OMEGA/MEX and comparison with general circulation model predictions
Gondet, B.; Montmessin, F.; Bertaux, J. L. +2 more
We report the first detection in the atmosphere of Mars of the nightside O2(a1Δg) emission at 1.27 µm from limb observations of the OMEGA imaging spectrometer on board Mars Express (MEX). The emission, detected in three cases out of 40 observations, is due to recombination in a downwelling air parcel of O ato…
Density variations within the south polar layered deposits of Mars
Zuber, Maria T.; Plaut, Jeffrey J.; Phillips, Roger J. +3 more
The south polar layered deposits (SPLD) constitute the largest known reservoir of water on Mars. Previous studies solved for the best fit uniform density of the deposits using a forward approach. Here we invert for the lateral density variations in the layered deposit using gravity data from radio tracking of Mars Reconnaissance Orbiter, topograph…
Density and lithospheric thickness of the Tharsis Province from MEX MaRS and MRO gravity data
Pätzold, M.; Rosenblatt, P.; Le Maistre, S. +2 more
Radio science tracking of Mars Express (MaRS experiment) and Mars Reconnaissance Orbiter produced high resolution Martian gravity data. Applying localized spectral analysis on the new gravity data sets, we study the surface density and lithospheric elastic thickness in the Tharsis province. The gravity signal is predicted with geophysical models e…
Emitted power of Jupiter based on Cassini CIRS and VIMS observations
West, Robert A.; Baines, Kevin H.; Nixon, Conor A. +11 more
The emitted power of Jupiter and its meridional distribution are determined from observations by the Composite Infrared Spectrometer and Visual and Infrared Mapping Spectrometer onboard Cassini during its flyby en route to Saturn in late 2000 and early 2001. Jupiter's global-average emitted power and effective temperature are measured to be 14.10 …