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Geological, geomorphological, facies and allostratigraphic maps of the Eberswalde fan delta
Rossi, A. P.; Pondrelli, M.; Platz, T. +3 more
Geological, facies, geomorphological and allostratigraphic map of the Eberswalde fan delta area are presented. The Eberswalde fan delta is proposed as a sort of prototype area to map sedimentary deposits, because of its excellent data coverage and its variability in depositional as well as erosional morphologies and sedimentary facies. We present …
Geology of possible Martian methane source regions
Ehlmann, Bethany L.; Wray, James J.
Recent observations of methane on Mars suggest that spatially localized source regions are present. Here we discuss the surface morphology and mineralogy of these regions, focusing on features that may provide insights into mechanisms of methane production and/or release. Preliminary trends among methane source regions include old age, deep fractu…
Analysis of a Thaumasia Planum rift through automatic mapping and strain characterization of normal faults
Alegre Vaz, David
A new semi-automatic technique is presented to map and characterize tectonic features on Mars. Automatic strain estimation associated with normal faults is achieved for synthetic and real fault scarps on Mars. The application of this new technique to a small rift located in Thaumasia Planum allowed the segmentation of the rift. The defined segment…
Possible role of brines in the darkening and flow-like features on the Martian polar dunes based on HiRISE images
Möhlmann, D.; Kereszturi, A.; Berczi, Sz. +3 more
This work identifies and describes features of the changing seasonal frost-covered surface of Mars based on HiRISE images, and analyses the possibility that ephemeral liquid brine formation produces them. Because some of these dark features show flow-like appearance, and salts on Mars are present, liquid brines might be also present, possibly acco…
Venus lightning: Comparison with terrestrial lightning
Russell, C. T.; Wei, H. Y.; Zhang, T. L. +2 more
Terrestrial lightning is generated by the separation of electric charge residing on water-ice particles in clouds, a few kilometers above the electrically conducting surface of the Earth. It is detected optically, electromagnetically, and aurally. The majority of discharges occur within or between clouds with about one third discharging to the sur…
Planetary X-ray fluorescence analogue laboratory experiments and an elemental abundance algorithm for C1XS
Smith, David R.; Swinyard, Bruce M.; Gow, Jason +5 more
We have conducted laboratory experiments as an analogue to planetary XRF (X-ray fluorescence) missions in order to investigate the role of changing incidence (and phase) angle geometry and sample grain-size on the intensity of XRF from regolith-like samples. Our data provide evidence of a grain-size effect, where XRF line intensity decreases with …
Studying methane and other trace species in the Mars atmosphere using a SOIR instrument
Daerden, F.; Robert, S.; Neary, L. +7 more
Solar Occultation in the InfraRed (SOIR) is one of three spectrometers of the SPICAV/SOIR instrument suite ( Bertaux et al., 2007b) on board the Venus Express orbiter (VEX). VEX has been in orbit around Venus since April 2006 and to date SOIR has carried out over 674 measurements. Pre-launch and in-orbit performance analyses allow us to predict wh…
History of plains resurfacing in the Scandia region of Mars
Tanaka, Kenneth L.; Skinner, James A.; Fortezzo, Corey M. +2 more
We present a preliminary photogeologic map of the Scandia region of Mars with the objective of reconstructing its resurfacing history. The Scandia region includes the lower section of the regional lowland slope of Vastitas Borealis extending about 500-1800 km away from Alba Mons into the Scandia sub-basin below -4800 m elevation. Twenty mapped geo…
Atmospheric angular momentum variations of Earth, Mars and Venus at seasonal time scales
Lambert, S.; Rosenblatt, P.; Le Maistre, S. +4 more
Atmospheric angular momentum variations of a planet are associated with the global atmospheric mass redistribution and the wind variability. The exchange of angular momentum between the fluid layers and the solid planet is the main cause for the variations of the planetary rotation at seasonal time scales. In the present study, we investigate the …
Non-LTE CO limb emission at 4.7µm in the upper atmosphere of Venus, Mars and Earth: Observations and modeling
López-Puertas, M.; López-Valverde, M. A.; Gilli, G. +4 more
We report here on CO limb observations in Mars, Venus and Earth and their model simulations. A comparative study of the CO emission, including the most recent spacecraft observations of the three planets' atmospheres, has been performed. Strong daytime emissions near 4.7µm have been recently observed in the limb of the upper atmosphere of th…