| Piú viste - Mars Reconnaissance Orbiter (MRO) |
PSP_005748_1075_RED_abrowse~0.jpgBuried Crater in the SPLD (natural colors; credits: Lunexit)56 visiteThis image of the SPLD shows some of the layers cut off against other layers below and right of center. Geologists call this an “angular unconformity” because the layers do not conform to each other across this boundary.
In this case, the angular unconformity was probably caused by erosion of the SPLD followed by deposition of new SPLD on top of the eroded surface, but faulting could also have caused the observed unconformity.
Near the unconformity is an impact crater, one of dozens found on the SPLD. The presence of these craters implies that the surface of the SPLD has been relatively stable (i.e., little erosion or deposition) in the past few million years.
This is in stark contrast to the NPLD, on which craters are very rare, implying very recent erosion/deposition.MareKromium
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PSP_005392_0995_RED_abrowse-00~0.jpgImpact Crater on the South Polar Layered Deposits (context frame; MULTISPECTRUM - credits: Lunexit)56 visiteThis image covers a portion of the ice-rich SPLD.
Layers in the Mars Polar Regions are of great interest because layers in ice on the Earth, as in the Antarctic and Greenland ice caps, are known to contain records of past atmospheric, environmental, and climate conditions. By studying Mars Polar Layers, we hope to be able to understand the past climate and history of water on the Red Planet.MareKromium
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PSP_005456_1650_RED_abrowse-00~0.jpgHome Plate from Orbit (CTX Frame - Enhanced Natural Colors - elab. Lunexit)56 visitenessun commentoMareKromium
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PSP_006610_2035_RED_abrowse~0.jpgPotential MSL Landing Site near Mawrth Vallis (MULTISPECTRUM; credits: Lunexit)56 visiteMawrth Vallis contains clay minerals that formed by chemical alteration of rocks by water. It is one of the short list of potential sites that the Mars Science Laboratory Rover will land at, and the HiRISE team is working to find a safe place to land in this area.
This observation shows a wide variety of scientifically interesting terrains as well as some potential hazards for landing. The central part of the image is dominated by light-toned materials with curving fractures of many different sizes. These fractures do not have a preferred orientation, indicating that they did not form in response to some regional stress pattern.
Instead, they formed by some more uniform process, possibly the drying of a thick mud deposit or the gradual rebound of the area as the overlying material was eroded away. The scattered mounds and sand dunes may or may not prove to be a danger, but it is reassuring to see that many of the impact craters have been smoothed out with a filling of wind-blown sand.MareKromium
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PSP_006695_1415_RED_abrowse~0.jpgGullies in Sirenum Fossae (MULTISPECTRUM; credits: Lunexit)56 visiteThis image shows parts of Sirenum Fossae that are southwest of Gorgonum Chaos. Some of the troughs (Fossae) have gullies on their walls. Gullies are incised slope features that are thought to have formed by liquid water flowing down the slopes.
It is unknown whether the water came from the subsurface or above the surface. The plains around the troughs have a number of mesas and hills that might have formed from erosion of a once-larger rock unit.
The left side of the image shows some dark linear features which MIGHT BE Dust Devil Tracks.MareKromium
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PSP_005424_1700_RED_abrowse~0.jpgAurorae Chaos (MULTISPECTRUM; credits: Lunexit)56 visiteThis observation shows a portion of Aurorae Chaos, chaotic terrain East of the Vallis Marineris Canyon System. Aurorae Chaos extends from Capri and Eos Chasmata on the West, into Hydraotes and Aureum Chaos on the North and East.
Chaotic terrain is thought to form from subsurface collapse following volatile release. It is possible that the Martian crust was at one time enriched in ices that became gases or liquid at relatively low temperatures upon encountering a heat source or was violently shaken. These ices existed in spaces between soil particles. If a large volume of volatiles is suddenly released, then there is a large portion of the soil volume missing. The soil cannot support itself, so it collapses.
Since chaotic terrain is often located at the head of the Martian outflow channels (giant flood plains), it is also possible that the Chaotic Regions are the source of the fluids that formed the outflow channels.
Aurorae Chaos connects to outflow channels via other Chaotic Regions.MareKromium
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PSP_005095_0935_RED_browse~0.jpgSouth Pole Residual Cap (Swiss-Cheese Terrain Monitoring) - (Natural Colors; credits: Lunar Explorer Italia)56 visitenessun commentoMareKromium
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ESP_011648_1730_RED_abrowse-02.jpgOval Mesa on Ganges Mensa (and another "mistery" solved) - Full image, non-map projected and Natural Colors; credits: Lunar Explorer Italia56 visitenessun commentoMareKromium
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ESP_011648_1730_RED_abrowse-01.jpgOval Mesa on Ganges Mensa (and another "mistery" solved) - Full image, map projected, RAW b/w56 visitenessun commentoMareKromium
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ESP_011605_1170_RGB.jpgDefrosting Malea Patera (edm - possible True Colors; credits: Dr M. Faccin)56 visitenessun commentoMareKromium
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PSP_010420_2505_RED_abrowse.jpgSummer Ice in Vastitas Borealis (Natural Colors; credits: Lunar Explorer Italia)56 visiteMars Local Time: 15:02 (early afternoon)
Coord. (centered): 70,3° North Lat. and 341,4° East Long.
Spacecraft altitude: 317,0 Km (such as about 198,1 miles)
Original image scale range: 31,7 cm/pixel (with 1 x 1 binning) so objects ~ 95 cm across are resolved
Map projected scale: 25 cm/pixel
Map projection: EQUIRECTANGULAR
Emission Angle: 7,3°
Phase Angle: 68,5°
Solar Incidence Angle: 62° (meaning that the Sun is about 28° above the Local Horizon)
Solar Longitude: 142,7° (Northern Summer)
Credits: NASA/JPL/University of Arizona
Additional process. and coloring: Lunar Explorer ItaliaMareKromium
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PSP_010430_2115_RED_abrowse.jpgOlivine Deposits (Natural Colors; credits: Lunar Explorer Italia)56 visiteMars Local Time: 15:35 (middle afternoon)
Coord. (centered): 30,8° North Lat. and 79,7° East Long.
Spacecraft altitude: 289,8 Km (such as about 181,1 miles)
Original image scale range: 29,0 cm/pixel (with 1 x 1 binning) so objects ~ 87 cm across are resolved
Map projected scale: 25 cm/pixel
Map projection: EQUIRECTANGULAR
Emission Angle: 7,4°
Phase Angle: 44,2°
Solar Incidence Angle: 52° (meaning that the Sun is about 38° above the Local Horizon)
Solar Longitude: 143,1° (Northern Summer)
Credits: NASA/JPL/University of Arizona
Additional process. and coloring: Lunar Explorer ItaliaMareKromium
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