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Layered mantling deposits in northeast Arabia Terra, Mars: Noachian-Hesperian sedimentation, erosion, and terrain inversion
Head, James W.; Fassett, Caleb I.
Thick, layered mantling deposits of different ages occur in several nonpolar regions of Mars and are thought to represent volcanic ash and/or climate-related ice-dust deposition. One such deposit is a layered mantling unit that unconformably blanketed highlands terrain in northeast Arabia Terra during the Late Noachian and/or earliest Hesperian. S…
Recovery of surface reflectance spectra and evaluation of the optical depth of aerosols in the near-IR using a Monte Carlo approach: Application to the OMEGA observations of high-latitude regions of Mars
Bibring, J. -P.; Gondet, B.; Langevin, Y. +2 more
We present a model of radiative transfer through atmospheric particles based on Monte Carlo methods. This model can be used to analyze and remove the contribution of aerosols in remote sensing observations. We have developed a method to quantify the contribution of atmospheric dust in near-IR spectra of the Martian surface obtained by the OMEGA im…
Venus atmospheric circulation: Known and unknown
Limaye, Sanjay S.
After a pause of more than two decades, Venus' atmosphere is being explored again. Since April 2006, European Space Agency's Venus Express has been acquiring data, exploiting the near-infrared windows that allow us to peer into the deep night-side atmosphere. In June 2007, NASA's MESSENGER mission will fly past Venus on its way to Mercury, collect…
Hadriaca Patera: Insights into its volcanic history from Mars Express High Resolution Stereo Camera
Greeley, Ronald; Williams, David A.; Neukum, Gerhard +6 more
High Resolution Stereo Camera (HRSC) images of Hadriaca Patera, Mars, in combination with Mars Orbiter Camera (MOC), Mars Orbiter Laser Altimeter (MOLA), and Thermal Infrared Imaging System (THEMIS) data sets, reveal morphologic details about this volcano and enable determination of a chronology of the major geologic events through new cratering a…
Olympus Mons, Mars: Inferred changes in late Amazonian aged effusive activity from lava flow mapping of Mars Express High Resolution Stereo Camera data
Greeley, Ronald; Williams, David A.; Bleacher, Jacob E. +3 more
Lava flow mapping was conducted on a north-south transect of Olympus Mons using the European Space Agency's Mars Express High Resolution Stereo Camera (HRSC) image H0037. The HRSC image was coregistered to Mars Orbiter Laser Altimeter, Thermal Emission Imaging System, and Mars Orbiter Camera data, enabling lava flow structures to be differentiated…
Space weather at Venus and its potential consequences for atmosphere evolution
Luhmann, J. G.; Russell, C. T.; Kasprzak, W. T.
Space weather storms at the Earth are dominated by the magnetosphere's response to coronal mass ejections, or CMEs, whose disturbances propagate through the solar wind to 1 AU, and to a lesser extent by the pressure ridges associated with the interactions of solar wind streams with different properties. The interplanetary signatures of these event…
Evidence for late Hesperian lacustrine activity in Shalbatana Vallis, Mars
Reiss, Dennis; Di Achille, Gaetano; Ori, Gian Gabriele
An intravalley paleolake (more than 400 m deep) was detected along the course of Shalbatana Vallis from the evidence of shorelines and the occurrence of a few fan-delta deposits (including a Gilbert-type delta). The fronts of all the sedimentary deposits strikingly match the same topographic contours (2800 and 3000 m below the Martian datum), indi…
Geologic and spectral mapping of etched terrain deposits in northern Meridiani Planum
Arvidson, R. E.; Gendrin, A.; Poulet, F. +1 more
A ~1 km vertical section of etched terrain and hematite-bearing plains materials and nearby cratered terrain surfaces was mapped in the northern portion of Meridiani Planum using MOC, THEMIS, MOLA, and OMEGA data. The oldest materials are the cratered plains, which have 0.4 to 2.5 µm spectral reflectance dominated by a mix of low and high ca…
Remote sensing of surface pressure on Mars with the Mars Express/OMEGA spectrometer: 1. Retrieval method
Drossart, Pierre; Vinatier, Sandrine; Gendrin, Aline +7 more
Observing and analyzing the variations of pressure on the surface of a planet is essential to understand the dynamics of its atmosphere. On Mars the absorption by atmospheric CO2 of the solar light reflected on the surface allows us to measure the surface pressure by remote sensing. We use the imaging spectrometer OMEGA aboard Mars Expr…
Composition of the atmosphere of Venus below the clouds
Bézard, Bruno; de Bergh, Catherine
The composition of Venus' lower atmosphere, beneath the clouds, has been investigated through both in situ measurements and remote-sensing observations. In 1978 the mass spectrometers and gas chromatographs aboard the Venera 11-12 landers and Pioneer Venus Large probe returned unique information on the abundances of carbon dioxide, nitrogen, noble…