Mars Reconnaissance Orbiter (MRO)
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ESP_020061_1720_RED_abrowse-PCF-LXTT.jpgBright and Dark Plains (Absolute Natural Colors; additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)123 visiteThis HiRISE image shows a mixture of bright and dark Terrain along the plains just West of Ganges Chasma.
The concentration of these bright patches adjacent to an old Impact Crater suggests that the bright patches could represent Ejecta from when the crater formed.
This would be an interesting discovery because it would mean that a different unit underlies the Surface we now see. Alternatively, much of the Plains in this Region seem to have a dark surficial cover (probably aeolian debris). Where this darker debris has been removed by the wind, the underlying brighter substrate would be exposed.
Mineralogic information from the CRISM instrument would be very useful for determining if the bright patches contain minerals indicative of water - such as Clays - or if they are Basalts (produced from Volcanic Eruptions).MareKromium
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ESP_020077_1915_RED_abrowse-00.jpgRelatively fresh "Lunar-like" Unnamed Crater (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)84 visitenessun commentoMareKromium
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ESP_020086_2020_RED_abrowse-00.jpgUnnamed Crater with Light-toned Layered Bedrock (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)73 visitenessun commentoMareKromium
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ESP_020163_0980_RED_abrowse.jpgSouth Polar Features (Absolute Natural Colors; credits: Dr Paolo C. Fienga - Lunexit Team)103 visiteHiRISE images are monochromatic across much of the scene, but in the center we return color data. The color strip down the center of this image gives us insight into Aerosols (such as particles of Dust and Frost) suspended in the Atmosphere and the seasonal processes that get them there. In the Winter Mars' South Polar Region is covered by a layer of CO2 ice (dry ice).
In the Spring this ice evaporates from the top and the bottom of the Seasonal Ice Layer (typically a few centimeters thick). Where there are cracks in the ice, the gas from below escapes, carrying fine particles from the Surface up to the top of the ice. Larger particles fall back onto the ground in Fan-shaped Deposits pointing in a direction determined by the local winds. We see the smaller particles (Dust) suspended in the air locally over the cracks as the bluish tone over the Regions with Fans.
Over Regions without Fans, where Gas and Dust from the Surface are not escaping into the Atmosphere, the Surface is a more pinkish tone.MareKromium
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ESP_020204_1835_RED_abrowse-00.jpgNorthern Meridiani Planum (CTX Frame - Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team:)85 visitenessun commentoMareKromium
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ESP_020204_1835_RED_abrowse-01.jpgNorthern Meridiani Planum (EDM - Enhanced Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team:) 107 visitenessun commentoMareKromium
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ESP_020245_2190_RED_abrowse.jpgUnnamed Northern Crater with Gullies (Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)88 visitenessun commentoMareKromium
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ESP_020297_2045_RED_abrowse.jpgFeatures of Mawrth Vallis - Layering (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)104 visiteMawrth Vallis is a Martian Region that is famous for its "Mineral Diversity", which includes Clay minerals that formed by the chemical alteration of both rocks and loose “Regolith” (such as Soil) by water.
There is a high surface area of bedded Phyllosilicate (Clay) exposures (in a range of tens of kilometers), located in the Bright-Toned Materials.
The CRISM instrument working on the MRO Spacecraft detects a variety of Clay minerals here, which could signify different processes of formation.
The High Resolution of the HiRISE camera helps us to see and trace out Layers, Polygonal Fractures and, with CRISM, to examine the distribution of various minerals across the entire Surface.
In the light of the above considerations and data, this Surface comes out as scientifically compelling for the Mars Science Laboratory (MSL) Rover 'Curiosity' (this Region is one of the four candidate Landing Sites for the MSL).MareKromium
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ESP_020319_1470_RED_abrowse-PCF-LXTT.jpgIce-rich Lobate Debris-Aprons in Terra Promethei (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)153 visiteThis image shows a portion of a Lobate "Debris-Apron! along the bottom of a Hill in the Promethei Terra Region of Mars. This Region contains many such Mesas surrounded by Lobate Debris-Aprons that are thought to be ice-rich.
These Aprons have been interpreted as a variety of possible features including Rock Glaciers, ice-rich Mass Movements, or Debris-covered Glacial Flows. Recent radar data have shown them to be composed of nearly 100% pure ice.
Parallel Grooves and Ridges indicate the direction of flow.
Both the Debris-Apron and the Plains beyond it are blanketed with an ice-rich Mantle that is common throughout the Martian Mid-Latitudes. The Mantle Deposits are pitted and grooved perhaps due to the sublimation of ice. This Mantle is thought to have been deposited as snow around 10 million years ago during a period of high obliquity, when the Planet's Axis was more tilted and environmental conditions could have been more conducive to snowfall in these Regions.
Several small Impact Craters are visible on the Plains that appear to have been filled with Mantling Deposits that have subsequently been partially removed. These Craters give us clues to the erosional history of the Deposit.MareKromium
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ESP_020323_2050_RED_abrowse-PCF-LXTT.jpgFan-shaped Deposit (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team:)116 visiteThis HiRISE image shows a Fan-shaped Deposit at the distal end of a Valley. The Fan is approximately 3,5x3,7 Km in size. While other similar Fans on Mars display stair-step terracing along their edges, this particular Fan does not show any Terraces. There is a Valley, instead, that appears to be the source of material that now composes much of the Fan.
Martian Fans are thought to be either Alluvial or Deltaic in origin.
On Earth, Alluvial Fans form when material upslope is eroded and transported by water down a confined Valley until reaching a flatter, broader surface downslope where the material is deposited to produce a Fan-shaped Surface Feature .
Deltaic Fans, on the other hand, form when rivers transport sediment downstream until an unconfined and flatter surface is reached under water, at which time the sediment is deposited in a Fan-shape.
Whether the Martian Fan formed by Alluvial or Deltaic processes in unknown, but both processes require a fluid (most likely water) that carved the Valley and transported the sediment downstream.MareKromium
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ESP_020334_2065_RED_abrowse-PCF-LXTT-00.jpgErosional Deposit in Eastern Arabia Terra (CTX Frame - Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)136 visitenessun commentoMareKromium
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ESP_020334_2065_RED_abrowse-PCF-LXTT-01.jpgErosional Deposit in Eastern Arabia Terra (EDM - Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)137 visitenessun commentoMareKromium
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