Search Publications
Lunar mare deposits associated with the Orientale impact basin: New insights into mineralogy, history, mode of emplacement, and relation to Orientale Basin evolution from Moon Mineralogy Mapper (M3) data from Chandrayaan-1
Head, James W.; Mustard, John; Clark, Roger +6 more
Moon Mineralogy Mapper (M3) image and spectral reflectance data are combined to analyze mare basalt units in and adjacent to the Orientale multiring impact basin. Models are assessed for the relationships between basin formation and mare basalt emplacement. Mare basalt emplacement on the western nearside limb began prior to the Oriental…
Orbital observations of contemporary dune activity in Endeavor crater, Meridiani Planum, Mars
Chojnacki, Matthew; Moersch, Jeffrey E.; Michaels, Timothy I. +1 more
Although aeolian landforms are pervasive on Mars, evidence for contemporary activity has been limited. The next major campaign for the Mars Exploration Rover “Opportunity” is the investigation of the ∼20 km diameter Endeavor crater, ∼6 km to southeast of the rover's position as of December 2010. We present evidence from orbital imagery that eight …
Dayside ionosphere of Mars: Empirical model based on data from the MARSIS instrument
Gurnett, D. A.; Němec, F.; Morgan, D. D. +2 more
We present results of a systematic study of electron densities in the dayside Martian ionosphere measured by the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) instrument on board the Mars Express spacecraft. There are two distinct regions controlled by different physical mechanisms. The first region is located at altitudes up…
Winter and spring evolution of northern seasonal deposits on Mars from OMEGA on Mars Express
Bibring, J. -P.; Gondet, B.; Langevin, Y. +6 more
The OMEGA visible/near-infrared imaging spectrometer on Mars Express has observed the retreat of the northern seasonal deposits during Martian year 27-28 from the period of maximum extension, close to the northern winter solstice, to the end of the retreat at Ls 95°. We present the temporal and spatial distributions of both CO2
Geophysical implications of the long-wavelength topography of the Saturnian satellites
Nimmo, F.; Thomas, P. C.; Bills, B. G.
We use limb profiles to quantify the long-wavelength topography of the Saturnian satellites. The degree 2 shapes of Mimas, Enceladus, and Tethys are not consistent with hydrostatic equilibrium. We derive 2-D topographic maps out to spherical harmonic degree 8. There is a good correlation with topography derived from stereo techniques. If uncompens…
The mineralogy of late stage lunar volcanism as observed by the Moon Mineralogy Mapper on Chandrayaan-1
Head, J. W.; Besse, S.; Boardman, J. +11 more
The last major phases of lunar volcanism produced spectrally unique high-titanium basalts on the western nearside of the Moon. The Moon Mineralogy Mapper (M3) on Chandrayaan-1 has provided detailed measurements of these basalts at spatial and spectral resolutions necessary for mineralogical interpretation and mapping of distinct composi…
Modeling polarimetric radar scattering from the lunar surface: Study on the effect of physical properties of the regolith layer
Heggy, Essam; Wieczorek, Mark A.; Fa, Wenzhe
A theoretical model for radar scattering from the lunar regolith using the vector radiative transfer theory for random media has been developed in order to aid in the interpretation of Mini-SAR data from the Chandrayaan-1 and Lunar Reconnaissance Orbiter missions. The lunar regolith is represented as a homogeneous fine-grained layer with rough upp…
Dark aeolian sediments in Martian craters: Composition and sources
Poulet, F.; Jaumann, R.; Tirsch, D. +1 more
Our research focuses on the mineralogical characteristics of dark sediment deposits in Martian craters (dunes, dune fields, and sand sheets) and their local sediment sources, carried out on the basis of 70 selected localities. Morphological analyses reveal dark layers exposed in a number of crater walls, showing indications of material transport f…
New near-IR observations of mesospheric CO2 and H2O clouds on Mars
Bibring, Jean-Pierre; Gondet, Brigitte; Vincendon, Mathieu +2 more
Carbon dioxide clouds, which are speculated by models on solar and extra-solar planets, have been recently observed near the equator of Mars. The most comprehensive identification of Martian CO2 ice clouds has been obtained by the near-IR imaging spectrometer OMEGA. CRISM, a similar instrument with a higher spatial resolution, cannot de…
Remote compositional analysis of lunar olivine-rich lithologies with Moon Mineralogy Mapper (M3) spectra
Mustard, John F.; Clark, Roger N.; Head, James W. +10 more
A systematic approach for deconvolving remotely sensed lunar olivine-rich visible to near-infrared (VNIR) reflectance spectra with the Modified Gaussian Model (MGM) is evaluated with Chandrayaan-1 Moon Mineralogy Mapper (M3) spectra. Whereas earlier studies of laboratory reflectance spectra focused only on complications due to chromite …