Search Publications
Three-Dimensional Turbulence-Resolving Modeling of the Venusian Cloud Layer and Induced Gravity Waves: Inclusion of Complete Radiative Transfer and Wind Shear
Spiga, A.; Lebonnois, S.; Lefèvre, M.
Venus' convective cloud layers and associated gravity waves strongly impact the local and global budget of heat, momentum, and chemical species. Here we use for the first time three-dimensional turbulence-resolving dynamical integrations of Venus' atmosphere from the surface to 100-km altitude, coupled with fully interactive radiative transfer com…
The Spectral Nature of Titan's Major Geomorphological Units: Constraints on Surface Composition
Le Mouélic, S.; Rodriguez, S.; Sotin, C. +24 more
We investigate Titan's low-latitude and midlatitude surface using spectro-imaging near-infrared data from Cassini/Visual and Infrared Mapping Spectrometer. We use a radiative transfer code to first evaluate atmospheric contributions and then extract the haze and the surface albedo values of major geomorphological units identified in Cassini Synthe…
Ion Escape From Mars Through Time: An Extrapolation of Atmospheric Loss Based on 10 Years of Mars Express Measurements
Barabash, Stas; Nilsson, Hans; Holmström, Mats +2 more
Solar wind-driven atmospheric ion escape has long been hypothesized as a major influence on the evolution of the Martian atmosphere due to the lack of a Martian global dipole magnetic field. We use 10 years (2007-2017) of Mars Express data to quantify the ion escape rate over the fully sampled parameter space of upstream solar wind dynamic pressur…
Viscoelastic Tides of Mercury and the Determination of its Inner Core Size
Oberst, J.; Stark, A.; Steinbrügge, G. +3 more
We computed interior structure models of Mercury and analyzed their viscoelastic tidal response. The models are consistent with MErcury Surface, Space Environment, GEochemistry, and Ranging mission inferences of mean density, mean moment of inertia, moment of inertia of mantle and crust, and tidal Love number k2. Based on these constrai…
Geological Features and Evolution of Yardangs in the Qaidam Basin, Tibetan Plateau (NW China): A Terrestrial Analogue for Mars
Huang, Jun; Xiao, Long; Xu, Yi +6 more
Wind-eroded ridges known as yardangs are common in most arid desert regions on Earth, as well as on other planets, notably in the Medusae Fossae Formation (MFF) and Gale Crater on Mars. However, the formation and evolution of these various yardangs are not well understood, which, therefore, requires further studies by more terrestrial analogues. H…
Spatial, Seasonal, and Solar Cycle Variations of the Martian Total Electron Content (TEC): Is the TEC a Good Tracer for Atmospheric Cycles?
Indurain, Mikel; González-Galindo, Francisco; Witasse, Olivier +7 more
We analyze 10 years of Mars Express total electron content (TEC) data from the Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) instrument. We describe the spatial, seasonal, and solar cycle behavior of the Martian TEC. Due to orbit evolution, data come mainly from the evening, dusk terminator and postdusk nightside. The annual…
Topographic Expressions of Large Thrust Faults on Mars
Klimczak, Christian; Kling, Corbin L.; Byrne, Paul K.
On planets with little erosion, thrust faults produce broad, asymmetric, positive-relief, linear to arcuate ridges—often referred to as lobate scarps—that remain largely unaltered, such that their topographic expressions are a measure of the structural uplift caused by the displacement and associated country rock deformation of the faults. Here we…
Incision of Licus Vallis, Mars, From Multiple Lake Overflow Floods
Goudge, Timothy A.; Fassett, Caleb I.
Licus Vallis is a large valley (>350 km long, >2 km wide, and >150 m deep) that heads at the outlet breach of an 30 km diameter impact crater. We present observations of the geomorphology and topography of this paleolake outlet valley and associated tributary valleys to constrain the history of incision of the Licus Vallis system. Licus V…
Equatorial Oscillation and Planetary Wave Activity in Saturn's Stratosphere Through the Cassini Epoch
Fletcher, L. N.; Flasar, F. M.; Spiga, A. +4 more
Thermal infrared spectra acquired by Cassini/Composite InfraRed Spectrometer (CIRS) in limb-viewing geometry in 2015 are used to derive 2-D latitude-pressure temperature and thermal wind maps. These maps are used to study the vertical structure and evolution of Saturn's equatorial oscillation (SEO), a dynamical phenomenon presenting similarities w…
Fine Vertical Structures at the Cloud Heights of Venus Revealed by Radio Holographic Analysis of Venus Express and Akatsuki Radio Occultation Data
Tellmann, Silvia; Pätzold, Martin; Imamura, Takeshi +10 more
Radio occultation (RO) is one of the most efficient techniques for studying fine vertical structures in planetary atmospheres. However, the geometrical optics (GO) method, which has been used for the analysis of RO data, suffers blurring by the finite width (Fresnel scale) of the radio ray and cannot decipher multipath propagation, which also prev…