Search Publications
Estimates of seismic activity in the Cerberus Fossae region of Mars
Teanby, N. A.; Taylor, J.; Wookey, J.
The 2016 NASA InSight lander is the first planetary mission designed to study the deep interior of Mars. InSight's Seismic Experiment for Interior Structure (SEIS) package will quantify global and regional seismic activity and determine parameters like core properties, mantle composition, and Martian lithospheric thickness. An improved understandi…
Characteristics of pebble- and cobble-sized clasts along the Curiosity rover traverse from Bradbury Landing to Rocknest
Mangold, N.; Garvin, J.; Deen, R. G. +23 more
have assessed the characteristics of clasts along Curiosity's traverse to shed light on the processes important in the genesis, modification, and transportation of surface materials. Pebble- to cobble-sized clasts at Bradbury Landing, and subsequently along Curiosity's traverse to Yellowknife Bay, reflect a mixing of two end-member transport mecha…
Convection-driven compaction as a possible origin of Enceladus's long wavelength topography
Besserer, J.; Nimmo, F.; Roberts, J. H. +1 more
The long wavelength surface topography of Enceladus shows depressions about 1 km in depth and ∼102 km wide. One possible cause of this topography is spatially variable amounts of compaction of an initially porous ice shell, driven by spatial variations in heat flux. Here, we show that the heat flux variations associated with convection …
The structure of Mars lower atmosphere from Mars Express Radio Science (MaRS) occultation measurements
Tellmann, Silvia; PäTzold, Martin; HäUsler, Bernd +2 more
The Mars Express Radio Science Experiment (MaRS) investigates the lower and middle atmosphere of Mars between the surface and about 40 km with a very high vertical resolution. More than 600 profiles of temperature, pressure, and neutral number density were retrieved between 2004 and 2011 covering four Martian years (MYs 27-30). Radio occultation e…
A systematic mapping procedure based on the Modified Gaussian Model to characterize magmatic units from olivine/pyroxenes mixtures: Application to the Syrtis Major volcanic shield on Mars
Bibring, Jean-Pierre; Gondet, Brigitte; Bellucci, Giancarlo +7 more
et al. (2011) have developed an adapted version of the Modified Gaussian Model (MGM). The improvements allow the characterization of spectra of olivine-pyroxene(s) mixtures, addressing both modal composition and individual minerals chemical composition. This version of MGM is fully automated and operational with large amounts of hyperspectral imag…
3D morphometry of valley networks on Mars from HRSC/MEX DEMs: Implications for climatic evolution through time
Mangold, N.; Ansan, V.
valley networks have been identified mainly in the Noachian heavily cratered uplands. Eight dense branching valley networks were studied in Noachian terrains of Huygens, Newcomb and Kepler craters, south Tyrrhena Terra, and Thaumasia, in Hesperian terrains of Echus Plateau and west Eberswalde craters, and in Amazonian terrains of Alba Patera, usin…
Near-infrared optical constants of naturally occurring olivine and synthetic pyroxene as a function of mineral composition
Trang, David; Gillis-Davis, Jeffrey J.; Klima, Rachel L. +3 more
Radiative transfer theory will assist in determining olivine and pyroxene proportions and compositions from the surface of a planetary body composed of intimately mixed minerals. In order to use radiative transfer techniques, the model requires the optical constants of olivine and pyroxene. Optical constants are parameters that describe the degree…
Incorporation of a gravity wave momentum deposition parameterization into the Venus Thermosphere General Circulation Model (VTGCM)
Brecht, A. S.; Bougher, S. W.; Rafkin, S. +2 more
The gravity wave-drag parameterization of Alexander and Dunkerton (1999) was implemented into a Venus Thermosphere General Circulation Model (VTGCM) to investigate breaking gravity waves as a source of momentum deposition in Venus' thermosphere. Previously, deceleration of zonal jets on the morning and evening terminators in models was accomplishe…
New nitric oxide (NO) nightglow measurements with SPICAM/MEx as a tracer of Mars upper atmosphere circulation and comparison with LMD-MGCM model prediction: Evidence for asymmetric hemispheres
Montmessin, Franck; Bertaux, Jean-Loup; González-Galindo, Francisco +3 more
We report observations of NO nightglow with the Spectroscopy for the Investigation of the Characteristics of the Atmosphere of Mars (SPICAM) experiment on board the Mars Express (MEx) spacecraft. NO molecules emit an ultraviolet photon when N and O atoms (produced at high altitude in the thermosphere) recombine. Therefore, this emission is a trace…
A 1-D model of physical chemistry in Saturn's inner magnetosphere
Delamere, P. A.; Bagenal, F.; Fleshman, B. L. +1 more
Water vapor spewed out of Enceladus' geysers spreads across the Saturn system through dissociation, charge exchange, and neutral-neutral collisions. The combined effects of impact ionization by suprathermal electrons, charge-exchange between ions and neutrals, and radial transport of the plasma produce the observed distribution of ions and their t…