Results 141 to 150 of about 3,040 (184)
Some of the next articles are maybe not open access.
The composition of the Martian surface
Icarus, 1964Abstract It is generally believed that the desert areas of Mars are composed of limonite. This model of the surface, while based upon polarimetric, spectrometric, color, and albedo measurements, contradicts a reasonable geologic model. An examination of the evidence for limonite on Mars shows that the above measurements are ambiguous.
Roger A. Van Tassel, John W. Salisbury
openaire +1 more source
2008
Phenomenal new observations from Earth-based telescopes and Mars-based orbiters, landers, and rovers have dramatically advanced our understanding of the past environments on Mars. These include the first global-scale infrared and reflectance spectroscopic maps of the surface, leading to the discovery of key minerals indicative of specific past climate ...
openaire +1 more source
Phenomenal new observations from Earth-based telescopes and Mars-based orbiters, landers, and rovers have dramatically advanced our understanding of the past environments on Mars. These include the first global-scale infrared and reflectance spectroscopic maps of the surface, leading to the discovery of key minerals indicative of specific past climate ...
openaire +1 more source
Coupled Ferric Oxides and Sulfates on the Martian Surface
Science, 2007The Mars Exploration Rover (MER), Opportunity, showed that layered sulfate deposits in Meridiani Planum formed during a period of rising acidic ground water. Crystalline hematite spherules formed in the deposits as a consequence of aqueous alteration and were concentrated on the surface as a lag deposit as wind eroded the softer sulfate rocks.
Bibring, J.-P. +11 more
openaire +3 more sources
Science (New York, N.Y.), 2010
With the scarcity of factual data and the difficulty of applying crucial tests, many of the properties of the Martian surface remain a mystery; the planet may become a source of great surprises in the future. In the following, the conclusions are enumerated more or less in the order of their reliability, the more certain ones first, conjectures or ...
openaire +1 more source
With the scarcity of factual data and the difficulty of applying crucial tests, many of the properties of the Martian surface remain a mystery; the planet may become a source of great surprises in the future. In the following, the conclusions are enumerated more or less in the order of their reliability, the more certain ones first, conjectures or ...
openaire +1 more source
Permafrost features on the martian surface
Icarus, 1968Abstract Permanently frozen ground may be a distinct possibility in all latitudes on Mars. Mean shallow subsurface temperatures are below the freezing point of water. Given a supply of water, either meteoric or juvenile, minor topographic features will develop in permafrost areas.
F.Alton Wade, Jane Negus De Wys
openaire +1 more source
Weathering of Martian Surface Rocks
1986The early 1960s marked the beginning of an extremely important trend in Martian investigation, i.e., exploration by space missions. From 1962 to 1976 more than a dozen spacecraft in the framework Mars, Mariner, and Viking space missions were launched, providing new and important data on the composition and structure of the Martian atmosphere and soil ...
Yu. I. Sidorov, M. Yu. Zolotov
openaire +1 more source
A model of interaction of Phobos’ surface with the martian environment
Icarus, 2011Abstract We simulate space weathering of Phobos’ surface due to both sputtering by solar wind ions (H+ and He2+) and planetary protons, and surface material vaporization by micrometeoroids impact. Assuming an Iron-rich composition of Phobos’ regolith, we find that densities of neutral species (Fe, O, Al, Ca, Mg, Na) in the martian environment are in ...
Cipriani, Fabrice +4 more
openaire +3 more sources
Iron mineralogy of the martian surface with OMEGA spectrometer
2014 6th Workshop on Hyperspectral Image and Signal Processing: Evolution in Remote Sensing (WHISPERS), 2014Goal of this paper is mapping the 1 μm from the OMEGA spectra in order to study the Martian iron mineralogy. This study is based on the results of Carrozzo et al. [1]. Goal of this paper is to map the 1 μm absorption signature in OMEGA spectra, in order to study the Martian mineralogy.
Filippo Giacomo Carrozzo +2 more
openaire +1 more source
Scratching the surface of martian habitability
Science, 2014Are the right chemical ingredients enough to make a habitable planet?
openaire +1 more source
Mineral stability at the Martian surface
Journal of Geophysical Research, 1968Thermodynamic calculations of mineral stability fields under a range of predicted surface conditions for Mars indicate that goethite will be unstable except under the wettest and coldest parts (pH2O ∼ 10−6 atm, T < 200°K) of this range. If the planetary atmosphere is strongly reducing, as implied by some estimates of CO abundance, the measured water ...
openaire +1 more source