Mars Reconnaissance Orbiter (MRO)
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PSP_009917_1665_RED.jpgUnnamed Rayed Crater (natural colors; credits: Lunar Explorer Italia)54 visiteMars Local Time: 15:28 (early afternoon)
Coord. (centered): 13,4° South Lat. and 48,2° East Long.
Spacecraft altitude: 276,5 Km (such as about 172,8 miles)
Original image scale range: 27,7 cm/pixel (with 1 x 1 binning) so objects ~83 cm across are resolved
Map projected scale: 25 cm/pixel
Map projection: EQUIRECTANGULAR
Emission Angle: 22,5°
Phase Angle: 79,7°
Solar Incidence Angle: 62° (meaning that the Sun is about 28° above the Local Horizon)
Solar Longitude: 123,6° (Northern Summer)
Credits: NASA/JPL/University of Arizona
Additional process. and coloring: Lunar Explorer ItaliaMareKromium
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PSP_009927_1750_RED_abrowse-00.jpgExposed Layers in Gale Crater (Enhanced Natural Colors; credits: Lunexit)54 visiteGale Crater contains a massive central mound of layered material that has an average vertical thickness of almost 4 Km (about 2,4 miles), making it more than twice as thick as the layers exposed along the Grand Canyon on Earth.
Gale Crater is approximately 152 Km in diameter.MareKromium
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PSP_009927_1750_RED_abrowse-01.jpgExposed Layers in Gale Crater (EDM- Enhanced Natural Colors; credits: Lunexit)54 visiteThis edm is a small portion of a HiRISE image detailing the fine-scale layering evident in the upper mound. The layered deposits can be divided into 2 types: a lower mound with near-horizontal, flat layers, and an upper mound with more numerous, thinner layers (some of which have greater degree of tilt than the lower layers).
The origin of these thin, repetitive layers is unknown, but they likely reflect environmental changes that occurred while the layers were being deposited.
Today, erosion by wind scour has shaped them into the stair-step pattern that is reminiscent of parts of the American South-West.MareKromium
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PSP_009929_2020_RED_abrowse-00.jpgAncient Layered Rocks in Nili Fossae (ctx frame - natural colors; credits: Lunexit)54 visiteThis image covers a flat plain in the Nili Fossae Region of Mars. The portion shown here is roughly 400 meters, or 1/4 of a mile, across.MareKromium
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PSP_009929_2020_RED_abrowse-01.jpgAncient Layered Rocks in Nili Fossae (edm - natural colors; credits: Lunexit)62 visiteBright, fractured Bedrock is visible underlying Dunes or Ripples of Wind-Blown Sand.
The parallel, dark brown curves across the Bedrock Surface (underneath the Dunes) that can be seen in this edm frame, are the edges of successive rock layers.
These may appear dark because dark sand has become trapped at the edges of the layers. Successive layers in the bedrock are also exposed in the walls of degraded impact craters elsewhere in the ctx image.
The Layered Rocks here are billions of years old, and infrared spectra from the CRISM instrument have inferred that they contain minerals such as Clays and Carbonate that likely formed when liquid water chemically altered these rocks.
This evidence for past water activity, combined with the general flatness of this particular location, make it a good candidate Landing Site for future Mars Rover missions.MareKromium
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PSP_009942_2645_RED_abrowse-00.jpgSmall Crater on Planum Boreum (ctx frame - natural colors; credits: Lunexit)74 visiteImpact craters on the surface of Planum Boreum, popularly known as the North Polar Cap, are rare. This dearth of craters has lead scientists to suggest that these deposits may be geologically young (a few million years old), not having had much time to accumulate impact craters throughout their lifetime.
It is also possible that impacts into ice do not retain their shape indefinitely, but instead that the ice relaxes (similar to glass in an old window), and the crater begins to disappear.MareKromium
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PSP_009942_2645_RED_abrowse-01.jpgSmall Crater on Planum Boreum (edm - natural colors; credits: Lunexit)63 visiteThis edm frame shows an example of a rare, small crater (approx. 115 meters, or 125 yards, in diameter). Scientists can count these shallow craters to attain an estimate of the age of the upper few meters of the Planum Boreum Surface.
The colors come from the presence of dust and of ice of differing grain sizes. The blueish ice has a larger grain size than the ice that has collected in the crater. The reddish material is dust. The smooth area stretching to the upper right, away from the crater may be due to winds being channeled around the crater or to fine-grained ice and frost blowing out of the crater.MareKromium
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PSP_009945_1835_RED.jpgExhumed Impact Crater in Equatorial Layered Deposits (possible True Colors; credits: Lunar Explorer Italia)55 visiteMars Local Time: 15:30 (middle afternoon)
Coord. (centered): 3,4° North Lat. and 2,9° East Long.
Spacecraft altitude: 273,7 Km (such as about 171,1 miles)
Original image scale range: 27,4 cm/pixel (with 1 x 1 binning) so objects ~82 cm across are resolved
Map projected scale: 25 cm/pixel
Map projection: EQUIRECTANGULAR
Emission Angle: 6,2°
Phase Angle: 59,3°
Solar Incidence Angle: 54° (meaning that the Sun is about 36° above the Local Horizon)
Solar Longitude: 124,7° (Northern Summer)
Credits: NASA/JPL/University of Arizona
Additional process. and coloring: Lunar Explorer ItaliaMareKromium
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PSP_009945_2645_RED.jpgExposure of North Polar Basal Unit (possible True - but enhanced - Colors; credits: Lunar Explorer Italia)110 visiteMars Local Time: 14:37 (early afternoon)
Coord. (centered): 84,4° North Lat. and 343,5° East Long.
Spacecraft altitude: 330,4 Km (such as about 206,5 miles)
Original image scale range: 33,1 cm/pixel (with 1 x 1 binning) so objects ~99 cm across are resolved
Map projected scale: 25 cm/pixel
Map projection: EQUIRECTANGULAR
Emission Angle: 14,2°
Phase Angle: 53,9°
Solar Incidence Angle: 65° (meaning that the Sun is about 25° above the Local Horizon)
Solar Longitude: 124,7° (Northern Summer)
Credits: NASA/JPL/University of Arizona
Additional process. and coloring: Lunar Explorer ItaliaMareKromium
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PSP_009960_2235_RED.jpgInverted Channel with Phyllosilicates (possible True Colors; credits: Lunar Explorer Italia)63 visiteMars Local Time: 15:26 (early afternoon)
Coord. (centered): 43,4° South Lat. and 309,2° East Long.
Spacecraft altitude: 303,5 Km (such as about 189,7 miles)
Original image scale range: 60,7 cm/pixel (with 1 x 1 binning) so objects ~1,82 mt across are resolved
Map projected scale: 50 cm/pixel
Map projection: EQUIRECTANGULAR
Emission Angle: 6,6°
Phase Angle: 42,0°
Solar Incidence Angle: 48° (meaning that the Sun is about 42° above the Local Horizon)
Solar Longitude: 125,2° (Northern Summer)
Credits: NASA/JPL/University of Arizona
Additional process. and coloring: Lunar Explorer ItaliaMareKromium
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PSP_009966_1735_RED_abrowse-00.jpgInverted Channels and Yardangs in Aeolis Mensae (ctx frame - natural colors; credits: Lunexit)55 visiteThis image shows wind-eroded Layered Deposits in Aeolis Mensae. Aeolis Mensae is located close to the Volcanic Region of Elysium Planitia and near the boundary of the high-standing, heavily cratered Southern Hemisphere and the low, sparsely-cratered plains that cover most of the Northern Hemisphere of Mars.
MareKromium
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PSP_009966_1735_RED_abrowse-01.jpgInverted Channels and Yardangs in Aeolis Mensae (edm - natural colors; credits: Lunexit)54 visiteAeolis Mensae is well-known for its unusual features commonly related to wind activity on the Planet’s Surface. Near the bottom of the image (see the edm here) is a long, sinuous, flat-topped feature that has been exposed by wind erosion.
This sinuous ridge is one of several similar ridges in the region that are believed to be former stream channels now preserved in inverted relief.
On Earth, inverted relief occurs when formerly low-lying areas become elevated because the original depression is filled with materials, such as lava, that are more resistant to erosion than the surrounding terrain. In the case of stream channels, the streambed may contain larger rocks and/or sediments that have been cemented by chemicals precipitating from flowing water that remain, while adjacent fine material is blown away by the wind. In this location, it is most likely that water once flowed through this channel and deposited sediments that eventually filled the channel and became cemented.
Over time, wind eroded the surrounding surface leaving the remnant channel exposed as a raised flat-topped ridge.
On either side of the Inverted Channel and throughout the image are several linear, streamlined ridges oriented roughly South to North. These are Yardangs, such as streamlined remnants of material shaped by the action of sand-blown sediments that eroded away weaker material.
Landforms such as these are common in desert areas on Earth. The orientation of the Yardangs indicates the primary wind direction.MareKromium
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