Mars Reconnaissance Orbiter (MRO)
|
|
|
PSP_005456_1650_RED_abrowse-00~0.jpgHome Plate from Orbit (CTX Frame - Enhanced Natural Colors - elab. Lunexit)56 visitenessun commentoMareKromium
|
|
PSP_005456_1650_RED_abrowse-01.jpgHome Plate from Orbit (EDM; Natural Colors - elab. Lunexit)62 visiteIl MER Spirit è indicato da una Freccia Rossa (Red Arrow), ad approx. ore 05:30 di Home Plate (la struttura più chiara, posta sul lato Dx del frame ed in posizione mediana).MareKromium
|
|
PSP_005514_1360_RED_abrowse.jpgDunes on Rabe Crater's Floor (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)80 visitenessun commentoMareKromium
|
|
PSP_005514_1360_RED_abrowse~0.jpgDunefield inside Rabe Crater (False Colors - elab. Lunexit)57 visiteThis image shows part of the floor of Rabe Crater, a large (about 108 Km, or approx. 67 miles in diameter) impact crater in the Southern Highlands.
Dark dunes — accumulations of wind blown sand — cover part of crater's floor and contrast with the surrounding bright-colored outcrops. The extreme close-up view reveals a thumbprint-like texture of smaller ridges and troughs covering the surfaces of the larger dunes.
These smaller ripples are also formed and shaped by blowing wind in the thin atmosphere of Mars.
One puzzling question is why the dunes are dark compared with the relative bright layered material contained within the Crater.
The probable answer is that the source of the dark sand is not local to this Crater; rather, this topographic depression has acted as a sand trap that has collected material being transported by winds blowing across the plains outside the Crater. MareKromium
|
|
PSP_005514_1925_RED_abrowse.jpgSlope Streaks (Absolute Natural Colors; credits for the additonal process. and color.: Dr Paolo C. Fienga - Lunar Explorer Italia)201 visiteMars Local Time: 14:05 (early afternoon)
Coord. (centered): 12,2° North Lat. and 26,4° East Long.
Spacecraft altitude: 288,4 Km (such as about 180,3 miles)
Original image scale range: 28,9 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: 18,3°
Phase Angle: 57,3°
Solar Incidence Angle: 41° (meaning that the Sun is about 49° above the Local Horizon)
Solar Longitude: 322,6° (Northern Winter)
Credits: NASA/JPL/University of Arizona
Additional process. and coloring: Lunar Explorer ItaliaMareKromium
|
|
PSP_005571_0950_RED_abrowse-00~0.jpgSouth Polar Residual Cap Margin (context frame; MULTISPECTRUM - elab. Lunexit)54 visiteThis scene is about 2,7 Km (approx. 1,7 miles) long and shows part of the edge of the South Polar Residual Cap (...).
The relatively bright, grayish areas are the Residual Cap, and the darker, reddish areas are mostly likely covered by dust. The South Polar Residual Cap is made, for the most part, of Carbon Dioxide ice (commonly called "dry ice") and dust, with a little water ice in some places.MareKromium
|
|
PSP_005571_0950_RED_abrowse-01.jpgSouth Polar Residual Cap Margin (extra-detail mgnf; MULTISPECTRUM - elab. Lunexit)53 visiteIn this extra-detail mgnf one can see fractures in the Residual Cap ice near the margin and, farther in, circular depressions that, in some places, appear to have coalesced.
These depressions constitute what is called "Swiss Cheese Terrain" and it's fairly easy to see why. The Swiss cheese terrain is created when the CO2 goes directly from the solid state (ice) to a gaseous state (the more familiar CO2 gas) as temperatures warm during South Polar Summer.
Swiss Cheese Formation may also be linked in a complicated way to the behavior of major Martian Dust Storms.
Images like these, taken before and after dust storm events, can aid our understanding of that complicated relationship.MareKromium
|
|
PSP_005574_1720_RED_abrowse-00~0.jpgLayers and Slope-Streaks within Valleys along the Highland-Lowland Boundary (context frame - MULTISPECTRUM; credits: Lunexit)58 visiteThis image shows Slope Streaks and Layering on the walls of a valley along the border between the Martian Southern Highlands and Northern Lowlands (see the extra-detail mgnf. At the bottom of the valley and in the lower portion of the valley walls are many large dunes.
The Slope Streaks generally start at a point source and widen downslope as a single streak or branch into multiple streaks. Some of the Slope Streaks show evidence that downslope movement is being diverted around obstacles, such as large boulders. In particular, several of the Slope Streaks in this image appear to be diverting around individual dunes, with downslope movement occurring in the low troughs between the dunes. The darkest Slope Streaks are youngest and cross cut and lie on top of the older and lighter-toned Streaks.
The lighter-toned Streaks are believed to be dark streaks that are lightening with time as new dust is deposited on their surface.MareKromium
|
|
PSP_005574_1720_RED_abrowse-01.jpgLayers and Slope-Streaks within Valleys along the Highland-Lowland Boundary (extra-detail mgnf - MULTISPECTRUM; credits: Lunexit)56 visiteSlope Streak formation is among the few known processes currently active on Mars. Since the Slope Streaks in this image appear to superpose (lie on top of) the surfaces between individual dunes, the Streaks most likely formed more recently and are younger than the dunes.
Many hypotheses have been proposed for the formation of Slope Streaks including dry avalanching, geochemical weathering, liquid stains or flows, and moisture wickering.
Recent observations from HiRISE images have revealed that the dark interior of Slope Streaks is lower in elevation than the surroundings, suggesting that material must have been removed in the formation of the streak.MareKromium
|
|
PSP_005581_1815_RED_abrowse-PCF-LXTT.jpgPossible MSL Landing Site in Northern Meridiani Planum (Enhanced Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)232 visitenessun commentoMareKromium
|
|
PSP_005609_1470_RED_abrowse-00.jpgInside Hale Crater (CTX Frame; Natural Color credits: Lunexit)54 visiteChannels associated with Impact Craters were once thought to be quite rare. Scientists proposed a variety of unusual circumstances to explain them, such as impacts by Comets or precipitation caused by the impact event. As more of Mars is photographed with High-Resolution imagery, more craters surrounded by Channel Systems are being discovered.
The Channels in this HiRISE image are from Hale Crater, an exceptionally well-preserved 125 x 150 Km (approx. 78 x 93 mile) Impact Crater located on the Northern Rim of the Argyre Basin.
Hale Crater is roughly 170 Km (a little more than 100 miles) to the South/East.MareKromium
|
|
PSP_005609_1470_RED_abrowse-01.jpgInside Hale Crater (EDM n.1 - processing by NASA/JPL/Univ. of Arizona; Natural Color credits: Lunexit)55 visitenessun commentoMareKromium
|
|
| 2237 immagini su 187 pagina(e) |
 |
|
|
|
|
124 | |
|
|
|
|
