Mars Reconnaissance Orbiter (MRO)
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PSP_001750_1425.jpgSouthern Crater (side-view; credits: Dr M. Faccin)106 visitenessun commentoMareKromium
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PSP_001784_001454___2030_anaglyph-MF-LXTT1.jpgMartian Crossway (Hi-Def-3D; credits for the additional process.: Dr Marco Faccin - Lunexit Team)133 visitenessun commentoMareKromium
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PSP_001784_001454___2030_anaglyph-MF-LXTT2.jpgMartian Crossway (Hi-Def-3D; credits for the additional process.: Dr Marco Faccin - Lunexit Team)120 visitenessun commentoMareKromium
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PSP_001808_1875_RED_abrowse-00.jpgSlope Streaks in Terra Sabaea (CTX Frame - Natural Colors; credits: Dr Paolo C. Fienga - Lunexit Team)57 visiteThis observation shows part of the rim of an Unnamed Crater in the Terra Sabaea Region - Northern Hemisphere of Mars. MareKromium
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PSP_001808_1875_RED_abrowse-01.jpgSlope Streaks in Terra Sabaea (EDM - Natural Colors; credits: Dr Paolo C. Fienga - Lunexit Team)54 visiteThis EDM is a close-up view of the Crater Rim revealing dark and light-toned Slope Streaks. Slope Streaks' formation is among the few known processes currently active on Mars. While their mechanism of formation and triggering is debated, they are most commonly believed to form by downslope movement of extremely dry sand or very fine-grained dust in an almost fluidlike manner (analogous to a terrestrial snow avalanche) exposing darker underlying material.
Other ideas include the triggering of Slope Streaks' formation by possible concentrations of near-Surface ice or scouring of the Surface by running water from aquifers intercepting slope faces, Spring Discharge (perhaps brines) and/or hydrothermal activity.
Several of the Slope Streaks seen here, particularly the 3 longest darker Streaks, show evidence that downslope movement is being diverted around obstacles such as large boulders. Several Streaks also appear to originate at boulders or clumps of rocky material.
In general, the Slope Streaks do not have large deposits of displaced material at their downslope ends and do not run out onto the Crater Floor suggesting that they have little reserve kinetic energy. The darkest Slope Streaks are the youngest and can be seen to cross cut and superpose older and lighter-toned Streaks.
The lighter-toned streaks are believed to be dark streaks that have lightened with time as new dust is deposited on their surface.MareKromium
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PSP_001816_1410_RED_abrowse-00.jpgGullies and arcuate Ridges in Terra Cimmeria (Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)54 visitenessun commentoMareKromium
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PSP_001897_1745_red_abrowse-PCF-LXTT.jpgLayering in Gale Crater (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team) 59 visitenessun commentoMareKromium
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PSP_001908_1405_red-PCF-LXTT.jpgUnnamed Southern Crater with Gullies (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)284 visitenessun commentoMareKromium
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PSP_001910_2215_RED_abrowse-00.jpgUnnamed Crater in Utopia Planitia (Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)54 visiteThis observation shows an Unnamed Impact Crater located in Utopia Planitia; this Crater is more than 10 Km (6,25 miles) in diameter and approx. 700 meters (765 yards) deep. Different features in and around this Crater may indicate the presence of fluid beneath the Surface.
Linear features radiating outward from the Crater's Rim are evident. Closer examination shows these features are formed by rocks and finer soils that are located along a straight line; technically, they are "Spokes" produced immediately after the impact by very fast outward-moving materials ejected from the contact-zone. Because these Ejecta came from deep under the Crater, their composition will tell us what type of rocks are under the Surface.
A MOC context image of this Crater shows its Ejecta Materials form an elevated "Pedestal," shaped like a pancake. The Pedestal is approx. 20 Km (about 12,5 miles) in diameter. "Pedestal craters" such as this may have formed because ice beneath the Surface melted when the impact occurred.MareKromium
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PSP_001916_2220_RED_abrowse.jpgKnobs and Mounds on the Northern Plains (Natural Colors; credits: Dr Paolo C. Fienga - Lunexit Team)54 visiteLight-toned Mounds occur across the image.
The northern part of the image is dominated by small Knobs or Patches, while there are features hundreds of meters across to the South. The larger features frequently have one or more craters and an irregular shape; it has been proposed that these features are Mud Volcanoes, which erupt mud instead of lava.
On Earth, Mud Volcanoes usually form in conditions of tectonic pressurization or rapid burial of sediments.
At high resolution, the Knobs show some fine lineations which may be wind-blown material, but are otherwise very smooth. In between the Mounds, the Surface is rough and rich in Boulders. The few Boulders on the Mounds were likely ejected from nearby Impact Craters.
Information like this from HiRISE images provides useful constraints on the formation and material of these Knobs and Cones.MareKromium
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PSP_001936_1370_RED_abrowse-01.jpgScarp and Channels in a Crater in Terra Cimmeria (Natural Colors; credits: Dr Paolo C. Fienga - Lunexit Team)59 visitenessun commentoMareKromium
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PSP_001936_1370_RED_abrowse-02.jpgUnnamed Crater in Terra Cimmeria (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)90 visitenessun commentoMareKromium
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