Search Publications
The impact of turbulent vertical mixing in the Venus clouds on chemical tracers
Marcq, Emmanuel; Lefèvre, Franck; Lefèvre, Maxence
Venus' clouds host a convective layer between roughly 50 and 60 km that mixes heat, momentum, and chemical species. Observations and numerical modelling have helped to understand the complexity of this region. However, the impact on chemistry is still not known. Here, we use for the first time a three-dimensional convection-resolving model with pa…
Discordance analysis on a high-resolution valley network map of Mars: Assessing the effects of scale on the conformity of valley orientation and surface slope direction
Bahia, Rickbir S.; Covey-Crump, Stephen; Jones, Merren A. +1 more
Fluvial valleys incised into planetary surfaces display morphologies, geometries and orientations that can be used to understand their controlling processes. Comparisons between valley orientations and topographic surface slope direction have been used to understand how Martian surfaces have evolved (Luo and Stepinski, 2012; Black et al., 2017); h…
Energy deposition in Saturn's equatorial upper atmosphere
Hu, X.; Galand, M.; Yelle, R. V. +6 more
We construct Saturn equatorial neutral temperature and density profiles of H, H2, He, and CH4, between 10-12 and 1 bar using measurements from Cassini's Ion Neutral Mass Spectrometer (INMS) taken during the spacecraft's final plunge into Saturn's atmosphere on 15 September 2017, combined with previous deeper atmosp…
Investigating the most promising Yarkovsky candidates using Gaia DR2 astrometry
Oszkiewicz, Dagmara; Bartczak, Przemysław; Dziadura, Karolina
The Yarkovsky drift is a major factor driving the orbital evolution of asteroids. To date, the effect has been detected for a few hundred asteroids, mainly near-Earth objects. Before the start of the European Space Agency Gaia mission, the expectation was to recognize many other asteroids manifesting the Yarkovsky drift through the high precision …
Machine learning as a tool to classify extra-terrestrial landslides: A dossier from Valles Marineris, Mars
Rajaneesh, A.; Vishnu, C. L.; Oommen, T. +2 more
Many researchers studied Martian landslides, and most of these studies are in the Valles Marineris (VM). Those studies are mainly morphologic analysis, estimates of landslide deposit volumes, thermal properties of the landslides, spectral analyses, and mapping and classifying landslides. But, this study created a robust landslide inventory of 682 …
Constraints on the uncertainty, timing, and magnitude of potential Mars oceans from topographic deformation models
Rivera-Hernández, Frances; Sholes, Steven F.
Proposed ocean paleoshorelines on Mars have faced criticism over their genetic interpretation and because they deviate significantly from an expected equipotential surface (by many kilometers). Multiple geophysical deformation models have been proposed to explain this large topographic range and deviation including true polar wander and direct Tha…
Investigating the origin of gypsum in Olympia Undae: Characterizing the mineralogy of the basal unit
Mustard, J. F.; Das, E.; Tarnas, J. D. +2 more
The Olympia Undae sand sea contains the largest known deposit of gypsum discovered on the surface of Mars. The origin of this gypsum, a hydrated sulfate mineral requiring liquid water for its formation, remains largely unconstrained. We examine the hypothesis that gypsum was derived from the early-Amazonian aged Basal Unit, which is suggested to c…
Atmospheric processes affecting methane on Mars
Rauer, H.; Arnold, G.; Herbst, K. +6 more
It is currently uncertain as to whether methane exists on Mars. Data from the Curiosity Rover suggests a background methane concentration of a few tenths parts per billion whereas data from the Trace Gas Orbiter suggest an upper limit of twenty parts per trillion. If methane exists on Mars then we do not understand fully the physical and chemical …
Convective storms in closed cyclones in Jupiter: (II) numerical modeling
Hueso, Ricardo; Sánchez-Lavega, Agustín; Legarreta, Jon +1 more
On May 31, 2020 a convective storm appeared in one small cyclone in the South Temperate Belt (STB) of Jupiter. The storm, nicknamed as Clyde's Spot, had an explosive start and quickly diminished in activity in a few days. However, it left a highly turbulent cyclone as a remnant that evolved to become a turbulent segment of the STB in a time-scale …
Numerical simulations of radar echoes rule out basal CO2 ice deposits at Ultimi Scopuli, Mars
Orosei, Roberto; Cartacci, Marco; Cicchetti, Andrea +10 more
The principal objective of the radar sounder MARSIS experiment is to look for ice and water in the Martian subsurface. One particular focus of investigations, since 2005, has been the search for basal liquid water in the south polar layered deposits (SPLD). Anomalously strong basal echoes detected from four distinct areas at the base of the deposi…