| Risultati della ricerca nelle immagini - "Richardson" |
Craters-RichardsonCrater-20090805a.jpgRichardson Crater (Daytime IR Light)64 visiteCaption NASA:"This Daytime IinfraRed image shows part of the dunes and deposit in Richardson Crater. The bright tone is due to the warm temperature of the dunes during the daytime".
Coord.: 72,8° South Lat. and 177,7° East Long.MareKromium
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Craters-Richardson_Crater-20090730a-1.jpgThe Dunes of Richardson Crater (Natural Colors; credits: Lunexit)71 visiteCoord.: 72,3° South Lat. and 180,2° East Long.MareKromium
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Craters-Richardson_Crater-20090806a.jpgRichardson Crater (Visible Light and Natural Colors; credits: Lunexit)71 visiteCaption NASA:"This VIS image of Richardson Crater was collected at the same time as yesterday's IR image. While the dunes appeared uniform in temperature in the IR, they are varied in appearance in the visible wavelengths. The sand is darker than the surrounding and covering dust".
Coord.: 72,2° South Lat. and 178,5° East Long.MareKromium
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Craters-Richardson_Crater-20090909a.jpgRichardson Crater (Natural Colors; credits: Lunexit)66 visiteCoord.: 72,1° South Lat. and 179,9° East Long. (center of the frame)MareKromium
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Craters-Richardson_Crater-Dunefield-20090403a-PCF-LXTT.jpgDunefield in Richardson Crater (Saturated and Enhanced Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunar Explorer Italia)54 visiteCaption NASA:"This VIS image shows the large Dunefield in Richardson Crater. Many Craters around the South Pole of Mars contain Dunefields".
Coord.: 72,3° South Lat. and 179,8° East Long.MareKromium
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Craters-Richardson_Crater-Dunefield-PIA13849-PCF-LXTT.jpgThe "Frozen Dunefield" of Richardson Crater (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)241 visiteOrbit Number: 39979
Latitude: 72,211° South
Longitude: 181,089° East
Instrument: VIS
Captured: december, 19th, 2010
Mars Local Time: 19:03:46 (Early Evening Hours)MareKromium
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Craters-Richardson_Crater-PIA13774.jpgDunes on Richardson Crater's Floor (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)131 visiteMareKromium
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Dunes-PIA13268-PCF-LXTT.jpgDunes in Richardson Crater (EDM - Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)56 visiteThis observation from NASA's Mars Reconnaissance Orbiter (MRO) is a view of the Sand Dunefield in Richardson Crater, still partually covered with seasonal frost.
This EDM is a close-up view of defrosting patterns on the Dunes. The frost is a combination of frozen CO2 and some water ice that covers the Dunes in the Winter and Spring. As the seasonal frost sublimes away, odd features such as spots, fans, and streaks form.
Small dark streaks on the dune slip-face slopes may be where recent avalanches of sand, or perhaps wind, has moved the dark sand underlying the frost, or where frost has been removed to expose the sand. Alternatively, the dark streaks may be patches of coarse-grained ice that are clear enough so that the dark material below the ice is visible.
The slip-faces indicate the general direction of sand transport.
It has been hypothesized that the Dark Spots and Fans may be "geysers" or "cold gas jets" that form when sublimation processes trap gas at the bottom of the ice. The gas is released through cracks in the ice, entraining dust from below the ice and scattering it onto the Surface to form the Dark Spots and Fans.MareKromium
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ESP_012774_1080_RED_abrowse-00.jpgDefrosting Dunes in Richardson Crater (ctx frame - Natural Colors; credits: Lunar Explorer Italia)54 visiteThis image shows a portion of the Dunes that fill Richardson Crater, a 55-Km-diameter crater in the South Polar Region of Mars and a frequent repeat target for the HiRISE camera.
During Southern Fall and Winter, these Dunes are coated with seasonal CO2 frost, which then sublimates into the Atmosphere as the temperature rises in Spring and Summer.
This Natural Color shows a boundary between Dunes that are mostly covered with Seasonal Frost and Dunes that have mostly thawed. The color of many dunes on Mars can change dramatically depending on the Season. Frost tends to be very bright in HiRISE images, particularly in the blue-green filter, but the Dune sand itself is very dark.
The dark streaks and spots on the frost-covered regions represent areas that are in the process of thawing out. In some areas, the frost has sublimated away. In others, a small avalanche of sand or dust may have spilled on top of the frost. Some of them may also be patches of coarse-grained ice that are relatively clear so that we can see the sand below. As Spring advances toward Summer in the South on Mars, these Dunes continue to appear darker and more red to HiRISE.
Dunes near the Polar Regions of Mars are studied both by scientists who are interested in the effects of this seasonal cycle of thawing and frosting over, and by scientists who wait for the frost to disappear so that they can study the dunes themselves.MareKromium
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ESP_012774_1080_RED_abrowse-01.jpgDefrosting Dunes in Richardson Crater (edm - Natural Colors; credits: Lunar Explorer Italia54 visitenessun commentoMareKromium
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ESP_023956_1075_RED_abrowse-PCF-LXTT.jpgThe Beautiful Dunefield inside Richardson Crater (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)212 visiteMars Local Time: 14:54 (Middle Afternoon)
Coord. (centered): 72,1° South Lat. and 180,9° East Long.
Spacecraft altitude: 250,8 Km (such as about 156,7 miles)
Original image scale range: 50,2 cm/pixel (with 2 x 2 binning) so objects ~ 1 mt and 51 cm across are resolved
Map projected scale: 50 cm/pixel
Map projection: POLAR STEREOGRAPHIC
Emission Angle: 8,6°
Sun-Mars-Spacecraft (or "Phase") Angle: 71,1°
Solar Incidence Angle: 76° (meaning that the Sun is about 14° above the Local Horizon)
Solar Longitude: 356,3° (Northern Winter)
Credits: NASA/JPL/University of Arizona
Additional process. and coloring: Dr Paolo C. Fienga - Lunar Explorer ItaliaMareKromium
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PSP_004230_1080_RED_abrowse.jpgDefrosting Dunefield inside Richardson Crater (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)83 visiteCovered by Seasonal CO2 Frost, the Dunefield here in Richardson Crater has only partially defrosted, although the image was acquired late in Mars' Southern Spring.
Large patches of Carbon Dioxide Frost can be observed, linked in some places by Channels possibly carved into the ground by the erosion of CO2 gas, as blocks dry ice slide down slope and sublimate.
Numerous Dust Devil Tracks (or DDT for short) have left their mark.
MareKromium
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