| Ultimi arrivi - Mars Reconnaissance Orbiter (MRO) |
PSP_008591_2485_cut_b.jpgPhoenix! (Natural Colors; credits: NASA/JPL/University of Arizona)55 visitenessun commentoMareKromiumMag 28, 2008
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PSP_008591_2485_cut_c.jpgBack-Shell and Parachute (MULTISPECTRUM; credits: Lunexit)64 visitenessun commentoMareKromiumMag 28, 2008
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PSP_008591_2485_cut_e.jpgPhoenix Lander "Hardware" (Day-Time Frame; MULTISPECTRUM process.)56 visitenessun commentoMareKromiumMag 28, 2008
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PSP_008585_2915_.jpgPhoenix Lander "Hardware" (Night-Time Frame)55 visiteCaption NASA:"MRO's HiRISE camera acquired this image of the Phoenix Landing Site 11 hours after landing. The image shows 3 unusual features, which were not present in the earlier, pre-landing HiRISE image.
We expect to find three main pieces of hardware: the Parachute attached to the Back-Shell, the Heat-Shield, and the Lander itself. The Parachute (lower right) is easy to identify because it is especially bright, although this image doesn't clearly reveal the Back-Shell.
The double dark marking at upper right seems most consistent with disturbance of the ground from impact and bouncing of the Heat-Shield, which fell from a height of about 13 Km.
The last object (upper left) appears to be a about the right size and height for the Lander and with dark objects on each side (to the East and West) consistent with the solar arrays.
This image was acquired in the nighttime, when the Arctic Sun was only 12° above the horizon to the North-East. Later images will be acquired in the daytime with the Sun higher in the sky and to the South-West, and could confirm our initial interpretations. North is about 7° to the left of straight up in this image.
These objects were later confirmed on the subsequent HiRISE observation acquired 22 hours after landing".MareKromiumMag 28, 2008
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PSP_008591_2485_cut_a.jpgPhoenix Lander "Hardware" (Day-Time Frame)56 visiteCaption NASA:"MRO’s HiRISE camera acquired this image of the Phoenix Landing Site 22 hours after landing. The image shows three unusual features which were not present in a pre-landing HiRISE image.
We expect to find three main pieces of hardware: the parachute attached to the backshell, the heat shield, and the lander itself.
The Parachute (bottom) is easy to identify because it is especially bright, and this image also clearly shows the Back-Shell. We can even see the stripes on the Parachute.
The dark marking (middle right) appears most consistent with disturbance of the ground from impact and bouncing of the Heat-Shield, which fell from a height of about 13 kilometers.
The last object (top) is the Lander, and we can clearly see the solar arrays on each side. The solar arrays were relatively dark in the image acquired 11 hours after landing, but are brighter than the Mars surface in this daytime image acquired with the HiRISE blue-green filter.
There are dark halos around all three locations, perhaps due to disturbing a thin dust coating.
North is about 7°to the right of straight up in this image and illumination is from the lower left".MareKromiumMag 28, 2008
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Polygons-PIA10658.jpgMartian and Earthly Polygons (comparison)60 visiteSome High-Latitude Areas on Mars (left) and Earth (right) exhibit similarly patterned ground where shallow fracturing has drawn Polygons on the surface. This patterning may result from cycles of freezing and thawing (---> disgelo).
The left image shows ground within the targeted landing area NASA's Phoenix Mars Lander before the Winter frost had entirely disappeared from the Surface. The bright ice in shallow crevices accentuates the area's polygonal fracturing pattern. The polygons are a few meters (several feet) across.
The image is a small portion of an exposure taken in March 2008 by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter.
The image on the right is an aerial view of similarly patterned ground in Antarctica.MareKromiumMag 25, 2008
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Weather-PIA10672.gifClear Skies over the Northern Regions (GIF-Movie; credits: NASA)58 visiteScientists are anticipating clear skies when NASA's Phoenix Mars Lander arrives on the north polar plains of the Red Planet Sunday, May 25, 2008.
This orbital view of the north polar region of Mars, where NASA's Phoenix Mars Lander will land, shows clear skies as of May 22, 2008. Mission planners are always on the lookout for dust storms in daily weather updates like this one, provided by the Mars Color Imager on NASA's Mars Reconnaissance Orbiter. Based on current conditions, they are predicting good weather when Phoenix arrives May 25, 2008.
Temperature profiles, used to calculate atmospheric density, are also updated on a regular basis, provided by the Mars Climate Sounder, another instrument on the Mars Reconnaissance Orbiter. Atmospheric density was well within expectations as of May 22, 2008. Mission planners will continue to receive updates on weather and atmospheric conditions prior to landing.
The animated orbital view shows recent weather conditions from May 16 to May 22, 2008, as tracked by the Mars Color Imager on NASA's Mars Reconnaissance Orbiter. A cloud of dust kicked up by Martian winds traveled from west to east between May 19 and May 22, 2008, passing over Phoenix's landing site. The dust cloud was about 500 kilometers (300 miles) from head to tail and made the skies somewhat hazy. Since then, the dust has been replaced by clear skies, indicating that Phoenix will not land in any dust clouds, which are a common occurrence in the northern latitudes of Mars.
MareKromiumMag 25, 2008
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PSP_007673_2575_RED_abrowse.jpgFrosted North Polar Crater (MULTISPECTRUM; credits: Lunexit)56 visiteThis image was taken over the North Polar Region of Mars, just South of the Layered Ice Cap.
The image shows a 10 Km diameter impact crater during Northern Spring, still covered by Carbon Dioxide ice/frost, and perhaps some water ice/frost.
There are color variations due to the presence of reddish dust mixed with the ice/frost in different proportions, and the dark and relatively blue spots form when CO2 is released in small jets from beneath the ice.
There are no clear examples of small impact craters superimposed on the large crater, although there are many shallow depressions that might be degraded craters.
This seems puzzling because small (approx. 10 meters in diameter) craters form much more frequently than 10 Km craters.
In fact, they form about a billion times more frequently! The reason why there aren’t any sharp small craters is due to the fact that the ice destroys them, and does so rapidly, compared with the cratering rate.
Ice on Mars does not melt in the current climate, but it does expand and contract with temperature variations and it can flow.MareKromiumMag 24, 2008
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PSP_008017_2020_RED_abrowse.jpgCraters in Isidis Planitia (MULTISPECTRUM; credits: Lunexit)68 visiteThis image shows a young impact crater in the Northern part of Isidis Planitia. The crater is fresh enough to preserve some fine textures that are eroded around other craters.
The ejecta blanket of material thrown out of the crater is distinctly dark and rough, with many small boulders and rugged texture. To the South of the crater there is a wedge-shaped area with little ejected material. This may indicate that the impactor which formed this crater came from the south, since at moderate impact angles ejecta is preferentially thrown in the direction of motion of the impactor.
Eventually, a combination of erosion and mantling by dust will smooth and obscure the ejecta and cover over the crater, turning it into a shallow depression like the others in this image. Reworking of the crater is already beginning, as shown by the network of fine ridges (wind-blown ripples) on the crater floor.MareKromiumMag 23, 2008
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PSP_007925_1990_RED_abrowse-00.jpgChannels in Jezero Crater Delta (context frame - MULTISPECTRUM; credits: Lunexit)77 visiteBillions of years ago, this water-carved channel in Nili Fossae Region transported sediments across the Martian Surface and deposited them on the floor of an impact crater just south of this image.
The sediments were deposited in a delta-like mound on the floor of Jezero Crater, suggesting that the crater may have contained a lake at the time.MareKromiumMag 23, 2008
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PSP_007925_1990_RED_abrowse-01.jpgChannels in Jezero Crater Delta (extra-detail mgnf - MULTISPECTRUM; credits: Lunexit)63 visiteThis extra-detail mgnf shows a section of one channel in greater detail. Wind-blown dunes or ripples now cover much of the channel floor, but in some places the older channel floor is visible. Here, the channel bed has a layered appearance. The plains outside the channel are fractured into polygonal patterns.
The CRISM instrument has detected water-bearing clay minerals in these plains, which were eroded by flows down the channel.
Clays are also seen in the sediments deposited on the floor of Jezero Crater.MareKromiumMag 23, 2008
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PSP_007338_2640.jpgNorth Polar Landslide (Special Processing by Dr M. Faccin)56 visitenessun commentoMareKromiumMag 22, 2008
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