Search Publications
Dications and thermal ions in planetary atmospheric escape
Simon Wedlund, C.; Ehrenreich, D.; Witasse, O. +4 more
In the recent years, the presence of dications in the atmospheres of Mars, Venus, Earth and Titan has been modeled and assessed. These studies also suggested that these ions could participate to the escape of the planetary atmospheres because a large fraction of them is unstable and highly energetic. When they dissociate, their internal energy is …
The density and temperature structure near the exobase of Saturn from Cassini UVIS solar occultations
Sandel, B. R.; Yelle, R. V.; Koskinen, T. T. +4 more
We analyzed 15 solar occultations observed by the Cassini UVIS instrument to constrain the density and temperature structure near the exobase of Saturn. We retrieved the density of H2 and thus the temperature at altitudes higher than 1900 km above the 1 bar level by analyzing the ionization continuum of H2 at wavelengths shor…
Comparing Dawn, Hubble Space Telescope, and ground-based interpretations of (4) Vesta
Nathues, Andreas; Russell, Christopher T.; Li, Jian-Yang +10 more
Observations of Asteroid (4) Vesta by NASA’s Dawn spacecraft are interesting because its surface has the largest range of albedo, color and composition of any other asteroid visited by spacecraft to date. These hemispherical and rotational variations in surface brightness and composition have been attributed to impact processes since Vesta’s forma…
Mineralogy of Mare Serenitatis on the near side of the Moon based on Chandrayaan-1 Moon Mineralogy Mapper (M3) observations
Bhattacharya, Satadru; Chauhan, Prakash; Kiran Kumar, A. S. +2 more
Spectral analysis of Mare Serenitatis has been carried out using Chandrayaan-1 Moon Mineralogy Mapper (M3) data in order to map the compositional diversity of the basaltic units that exist in the basin. Mare Serenitatis is characterized by multiple basaltic flows of different ages indicating a prolonged volcanism subsequent to the basin…
Impact of tidal heating on the onset of convection in Enceladus’s ice shell
Čadek, Ondřej; Tobie, Gabriel; Běhounková, Marie +1 more
By performing 3D simulations of thermal convection and tidal dissipation, we investigated the effect of tidal heating on the onset of convection in Enceladus’s ice shell. We considered a composite non-Newtonian rheology including diffusion, grain-size-sensitive and dislocation creeps, and we defined an effective tidal viscosity reproducing the dis…
Spectroscopic classification of icy satellites of Saturn I: Identification of terrain units on Dione
Stephan, K.; Capaccioni, F.; Cerroni, P. +4 more
Dione is one of the largest and densest icy satellites of Saturn. Its surface shows a marked asymmetry between its leading and trailing hemispheres, the leading side being brighter than the trailing side, which shows regions mantled by a dark veneer whose origin is likely exogenic. In order to identify different terrain units we applied the Spectr…
Ground-based near-infrared observations of water vapour in the Venus troposphere
Crisp, David; Bailey, Jeremy; Chamberlain, Sarah +1 more
We present a study of water vapour in the Venus troposphere obtained by modelling specific water vapour absorption bands within the 1.18 µm window. We compare the results with the normal technique of obtaining the abundance by matching the peak of the 1.18 µm window. Ground-based infrared imaging spectroscopy of the night side of Venus…
Reconciling main belt asteroid spectral flux density measurements with a self-consistent thermophysical model
Choukroun, Mathieu; Janssen, Michael; Keihm, Stephen +4 more
Thermophysical models consistent with Earth’s Moon and infrared and submillimeter measurements obtained during the Rosetta fly-by of Asteroid (21) Lutetia have been applied to computations of thermal fluxes from Asteroids (4) Vesta, (1) Ceres, (2) Pallas, and (10) Hygiea. Comparisons are made with Earth- and space-based flux measurements that cove…
Sunskirting comets discovered with the LASCO coronagraphs over the decade 1996-2008
Llebaria, A.; Lamy, P.; A'Hearn, M. F. +3 more
In addition to an unprecedented number of Kreutz sungrazing comets, the LASCO coronagraphs have discovered some 238 unrelated “sunskirting” comets over the 12 years from 1996 to 2008. This new class is organized in several groups, and at least two comets have further been found periodic. This article presents the photometry and the heliocentric li…
One Moon, many measurements 1: Radiance values
Yokota, Y.; Mall, U.; Besse, S. +10 more
Several modern optical instruments orbited the Moon during 2008 and 2009 onboard the SELENE and Chandrayaan-1 spacecraft and provided a welcomed feast of spectroscopic data to be used for scientific analyses. The different spatial and spectral resolutions of these sensors along with diverse illumination geometry during data acquisition make each s…