Mars Reconnaissance Orbiter (MRO)
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PSP_001406_2680_red-00.jpgLonely and (almost) buried crater in the North Polar "Permanent Cap" (CTX Frame - Natural Colors; credits: Dr Paolo C. Fienga - Lunexit Team)54 visitenessun commentoMareKromium
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PSP_001406_2680_red-01.jpgLonely and (almost) buried crater in the North Polar "Permanent Cap" (EDM - Natural Colors; credits: Dr Paolo C. Fienga - Lunexit Team)54 visitenessun commentoMareKromium
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PSP_001408_1900_RED_abrowse.jpgFlows in Athabasca Valles (Natural Colors; credits: Lunexit)54 visiteThin Flows cover the Plains just North of the Source Region for the Athabasca Valles Channel System. The Flows are mostly confined by a Scarp (Cliff) that can be seen in the North-Western corner of the image.
The more heavily Cratered Terrain above the Scarp is part of a tectonic ridge known as a "Wrinkle Ridge". A few Flows can be seen atop the Wrinkle Ridge, but they are not as ubiquitous as those on the Plains below. The Flows on the Plains frequently intersect, with younger ones cutting across older ones.
The prominent dark swathes along their edges have particularly rough textures.
The darker shade is due to thousands of shadows cast by small bumps on the Surface, which HiRISE is able to resolve.
Dozens of bright, narrow Rifts (Cracks) zigzag across the Flows. They appear bright because they are filled with light-toned, windblown material. Wind-sculpted Knobs and Ridges of similar light-toned material are scattered throughout the imaged area.
The orientations of the Ridges indicate that the Winds primarily blow from the South-East. Several impact craters are captured in this image, the largest being about 50 meters (160 feet) in diameter. Many bear the distinctive bright rays characteristic of secondary craters associated with the larger impact crater, Zunil.
Some craters penetrated the surface of the Flows, and the boulders strewn around them suggest that the material they excavated was rocky.MareKromium
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PSP_001410_2210_RED_abrowse.jpgUnnamed Craters with Layered Deposits in Utopia Planitia (Natural Colors; credits: Lunexit)54 visiteThis image shows an Unnamed Impact Crater located in Utopia Planitia (Northern Hemisphere of Mars) that is filled with layered material.
The layered character of these Deposits is consistent with episodic deposition. Each distinct layer represents a period of sediment deposition. The layers are parallel to each other, indicating that deposition occurred by material settling onto the Surface, rather than being blown across the Surface in Sand Dunes.
The hummocky texture of these deposits suggests that volatiles (such as Carbon Dioxide Ice) are mixed in with the rocky sediment.MareKromium
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PSP_001414_2165_RED_abrowse.jpgThe Dichotomy Boundary (Natural Colors; credits: Lunexit)54 visiteThis observation crosses over a part of the so-called "Dichotomy Boundary" of Mars, which is a Region of the Red Planet that separates the low-lying Northern Plains from the older Southern Highlands.
In the northern part of the scene (Dx), much of the surface is covered with small boulders, most only 1 to 2 meters wide (1 meter is approx. 1 yard). In other areas, it appears that sand or dust has accumulated in depressions, forming light patches. These areas also show short sinuous or linear features, likely ripples formed from wind-blown material.
The southern part (Sx) contains an old valley, now mantled by later deposits, and has a pitted texture due to erosion.
It has been proposed that the Lowlands were once filled by an ocean. If that is the case, then several arcuate or linear features along the Boundary slope could be old shorelines - but this interpretation is still debated. The features have been modified by erosion, and in some cases appear to slope towards the Highlands.MareKromium
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PSP_001415_1875_RED_abrowse.jpgAlluvial Fans in Mojave Crater (Natural Colors; credits: Lunexit)81 visiteAptly-named Mojave Crater in the Xanthe Terra Region has Alluvial Fans that look remarkably similar to landforms in the Mojave Desert of South-Eastern California and portions of Nevada and Arizona.
Alluvial Fans are "fan-shaped deposits of water-transported material" (---> Lat.: alluvium). They typically form at the base of hills or mountains where there is a marked break, or flattening of slope.
They typically deposit big rocks near their Mouths (close to the mountains) and smaller rocks at greater distances. Alluvial Fans form as a result of heavy desert Downpours, typically "Thundershowers" (Nota Lunexit: piogge torrenziali che occorrono durante violenti temporali, per lo più di tipo tropicale).
Because deserts are poorly vegetated, heavy and short-lived Downpours create a great deal of erosion and nearby deposition.
There are Fans inside and around the outsides of Mojave Crater on Mars that perfectly match the morphology of Alluvial Fans on Earth, with the exception of a few small impact craters dotting this Martian Landscape.
Channels begin at the apex of topographic Ridges, consistent with precipitation as the source of water, rather than groundwater. This remarkable landscape was first discovered from Mars Orbital Camera images. Mars researchers have suggested that impact-induced Atmospheric Precipitation may have created these unique landscapes.
This HiRISE image at up to 29 cm/pixel scale supports the Alluvial Fan interpretation, in particular by showing that the sizes of the largest rocks decrease away from the Mouths of the Fans.MareKromium
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PSP_001420_2045_RED_browse-00~0.jpgSmall Channel in Tartarus Colles (CTX Frame - Natural Colors; credits: Lunexit)54 visiteThis observation shows a thin channel between knobs in the Northern Hemisphere. These knobs are part of a local group of knobs called the "Tartarus Colles".
Both knobs visible in this image have dark slope streaks. It was originally thought that slope streaks might be locations of surface water wetting and darkening soil, but it is now commonly believed that slope streaks are mini-avalanches of dust. Slope streaks fade over time as wind erosion blends them in with their surroundings.MareKromium
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PSP_001420_2045_RED_browse-01~0.jpgSmall Channel in Tartarus Colles (EDM - Natural Colors; credits: Lunexit)66 visiteThe Channel between the Knobs has a variable depth as seen by the varying shadow lengths. The origin of the Channel is unknown, but it is probably NOT a Fluvial Channel because there are no obvious source or Deposit Regions; the Channel, therefore, is probably a Collapse Feature.
One portion of it, (see this EDM, approx. 375 meters across), contains a Bridge, and is probably a remnant of the original surface.
A depression that extends from the Channel Northwards — but which is not as deep as the majority of the Channel — might be in the process of collapsing and enlarging the Channel. MareKromium
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PSP_001422_1750_RED_abrowse.jpgLayers in Gale Crater Central Mound (Natural Colors; credits: Lunexit)54 visiteThis image shows a portion of the Central Mound in the Gale Crater (Central Mound that is of interest to scientists because of the light-toned Layered Deposits that can be found inside it).
The Layered Deposits could have formed in a water environment if, for instance, a lake - once - filled the Crater. Alternatively, particles suspended in the Atmosphere, such as Dust or Volcanic Ashes, could have built up the Layers over time.
By using HiRISE images to see details in the Layers, such as how their thicknesses vary horizontally and vertically, scientists can narrow down the potential origins.
The paucity of Impact Craters on the Layered Deposits indicates that either the Deposits are very young, or more likely that they are being eroded up to the point where such (alleged) Impact Craters were erased.
Wind Erosion modified the Layers after they formed, creating both sharp corners and rounded depressions along the Surface.
A few meter-size Boulders are visible at the base of some steep Cliffs, but the really poor amount of visible Boulders elsewhere suggests that most of the erosion occurred (and it is still occurring) because of eolic processes (such as wind action) rather than downslope movement of material.MareKromium
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PSP_001444_1915_red.jpgThe Layered Walls of Ascraeus Caldera (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)66 visitenessun commentoMareKromium
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PSP_001454_2030_and_001784_2030-Anagliph-MF-PCF-LXTT.jpgMawrth Vallis (High-Def-3D and Natural Colors; credits for the additional process. and color.: Drr Marco Faccin & Paolo C. Fienga - Lunexit Team)81 visiteAcquisition Date: 17 November 2006
Mars Local Time (MLT): 15:27 (Early Afternoon)
Latitude (centered): 22,8° North
Longitude (East): 341,7°
Range to Target Site: 284,1 Km (such as about 177,6 miles)
Original image scale range: 28,4 cm/pixel (with 1 x 1 binning) so objects ~85 cm across are resolved
Map projected scale: 25 cm/pixel and North is up
Map projection: EQUIRECTANGULAR
Emission angle: 1,2°
Sun-Mars-Spacecraft (or Phase) Angle: 47,7°
Solar Incidence Angle: 49° (with the Sun about 41° above the Local Horizon)
Solar Longitude: 136,9° - Northern SummerMareKromium
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PSP_001454_2030_zoom3d-00.jpgLayered Terrain Near Mawrth Valles Phyllosilicates (High-Def-3D - false colors; credits: DR M. Faccin)53 visite...Un'incredibile ricostruzione in High-Def-3D (realizzata dal Dr Faccin) di uno dei paesaggi più intriganti e suggestivi di Marte: Mawrth Vallis.
Indossate gli occhialini e poi guardate: Vi sembrerà di "volare" su Marte, a 284 Km di quota, aggrappati al nostro "Amico" Mars Reconnaisance Orbiter!
Mars Local Time: 15:27 (early afternoon)
Coord. (centered): 22,8° North Lat. and 341,7° East Long.
Spacecraft altitude: 284,1 Km (such as about 177,6 miles)
Original image scale range: 28,4 cm/pixel (with 1 x 1 binning) so objects ~85 cm across are resolved
Map projected scale: 25 cm/pixel
Map projection: EQUIRECTANGULAR
Emission Angle: 1,3°
Phase Angle: 47,6°
Solar Incidence Angle: 49° (meaning that the Sun is about 41° above the Local Horizon)
Solar Longitude: 136,9° (Northern Summer)
Credits: NASA/JPL/University of Arizona
Additional process.: Dr Marco FaccinMareKromium
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