Results 231 to 240 of about 34,777 (278)
Some of the next articles are maybe not open access.
The Martian Surface Composition
2001Mars is unique to have undergone all planetary evolutionary steps, without global resets, till its geological death: this is reflected in the variety of its surface features. The determination of Mars surface composition has thus the potential to identify the processes responsible for the entire Mars evolution, from geological timescales to seasonal ...
Jean-Pierre Bibring, Stéphane Erard
openaire +2 more sources
A calculation of the radiation environment on the Martian surface
Life Sciences in Space Research, 2017In this work, the radiation environment on the Martian surface, as produced by galactic cosmic radiation incident on the atmosphere, is modeled using the Monte Carlo radiation transport code, High Energy Transport Code-Human Exploration and Development in Space (HETC-HEDS).
Lawrence W. Townsend, Wouter de Wet
openaire +3 more sources
The morphology of the Martian surface
Space Science Reviews, 1980Most of the southern hemisphere of Mars is densely cratered and stands 1–3 km above the topographic datum. The northern hemisphere is more sparsely cratered and elevations are generally below the datum. A broad rise, the Tharsis bulge, centered at 14° S, 101° W, is 8000 km across and 10 km above the datum at its summit. The densely cratered terrain has
openaire +2 more sources
Stability of hydrous minerals on the martian surface [PDF]
The presence of water-bearing minerals on Mars has long been discussed, but little or no data exist showing that minerals such as smectites and zeolites may be present on the surface in a hydrated state (i.e., that they could contain H 2O molecules in their interlayer or extraframework sites, respectively).
Steve J. Chipera+3 more
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 +2 more sources
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 +2 more sources
Scratching the surface of martian habitability
Science, 2014Are the right chemical ingredients enough to make a habitable planet?
openaire +2 more sources
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 +4 more sources
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 ...
M. Yu. Zolotov, Yu. I. Sidorov
openaire +2 more sources
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 +4 more sources