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Rhea-EB-LXTT.jpgCratered Terminator (Absolute Natural Colors; credits for the additional process. and color.: Elisabetta Bonora and Paolo C. Fienga - Lunexit Team)55 visitenessun commentoMareKromium
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Saturnian_Sky-N00166739-47-EB-LXTT.jpgSaturnian Sky (Superdefinition - credits for the additional process.: Elisabetta Bonora - Lunexit Team)55 visitenessun commentoMareKromium
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Northern_Dunes-PIA13797-1.jpgSeasonal Changes in a Dune of the North Polar Erg55 visiteThree images of the same location taken at different times on Mars show seasonal activity causing Sand Avalanches and Ripple changes on a Martian Dune. Time sequence of the images progresses from top to bottom. Each image covers an area of 285 meters (312 yards) by 140 meters (153 yards). The Crest of a Dune curves across the upper and left portions of the image.
The High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter took these images. The site is at about 84° North Latitude and 233° East Longitude, in a vast Region of Dunes at the Edge of Mars' North Polar Ice Cap. The area is covered by Carbon-Dioxide (CO2) Ice in Winter but is Ice-free in Summer. The top and bottom images show part of one Dune about one Mars Year apart, at a time of the year when all the Seasonal Ice has disappeared: in late Spring of one year (top) and early Summer of the following year (bottom). The middle image is from the second year's mid-Spring, when the Region was still covered by Seasonal CO2 Ice.
Spring evaporation of the Seasonal Layer of Ice is manifested as Dark Streaks of fine particles carried to the top of the Ice Layer by escaping gas. The bottom of the Ice Layer, in contact with the Dark Ground, warms faster than the top of the Ice does in the Spring. Carbon-Dioxide gas produced by the thawing (----> disgelo) of the bottom Ice is temporarily trapped under the top Ice.
As the Ice evaporates from the bottom, flow of gas under the Ice destabilizes the Sand on the Dune, thus causing the Sand itself to avalanche down the Dune "Slipface".
A before-and-after comparison of the Dune shows new Alcoves and extension of the Debris Apron on the Slipface of the Dune caused by descending Grains of Sand. New Wind Ripples appear on the Debris Apron.
The top image is a portion of the HiRISE observation catalogued as PSP_008867_2640, taken on June 17, 2008.
The middle image is a portion of the HiRISE observation catalogued as ESP_016779_2640, taken on Feb. 23, 2010.
The bottom image is a portion of the HiRISE observation catalogued as ESP_018427_2640, taken on July 2, 2010.MareKromium
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PSP_002472_1810_red_abrowse-PCF-LXTT.jpgSlope Layers in Echus Chasma (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team:)55 visitenessun commentoMareKromium
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Eos_Chaos-PIA14282-PCF-LXTT.jpgFeatures of Eos Chaos (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)55 visitenessun commentoMareKromium
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PSP_005946_0975_RED_abrowse-00-PCF-LXTT.jpgUnconformity in the South Polar Layered Deposits - SPLD (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)55 visitenessun commentoMareKromium
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PSP_009087_2550_RED-PCF-LXTT.jpgUnnamed Crater with Dunefield in Vastitas Borealis (Absolute Natural Colors; credits for the additional process. and color: Dr Paolo C. Fienga - Lunexit Team)55 visiteThis North Polar Dunefield is bounded by a small Unnamed Crater about 11 Km in diameter in the Vastitas Borealis Region. This crater captured deposits of basaltic sand that may have been transported from the North Polar Erg, a massive sea of sand that surrounds the Martian North Pole.
This Region experiences a variety of winds that blow from various directions during different seasons and times of day, and the winds are also affected by the topography of the crater itself. This influences the movement of sand within the crater and the dunes that they shape.
This image shows many transitioning dunes which indicate changes of wind direction. The wind direction can be inferred from the location of the steeper side of the dune (called the slip-face) which is downwind of the dominant wind direction. The barchans and barchanoid dunes form crescent shapes and are consistent with dominant winds from the South-West.
Towards the center of the Dunefield, the barchans transition from crescent shapes into irregular, more elongated dunes and merge.
The more northern part of the Dunefield consists of longitudinal dunes which extend from the horns of the modified barchans residing in its central part.
These longitudinal dunes form along the trend of southerly-southeasterly winds.
Because it is early Summer, solar radiation has heated the sand and there are only a few small patches of frost remaining on the dunes at this season. However, evidence of the arctic climate is visible in the polygons surrounding the dune field.
The polygons, like those found at the Phoenix Mission Landing Site, are produced by freeze-thaw cycles as the polar soil expands and contracts. MareKromium
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SOL0003-ML0000034000E1_DXXX-0003ML0000039000E1_DXXX-GB-LXTT-2.jpgGale's Horizon, part II - Sol 3 (an Image Mosaic in RAW Natural Colors; credits for the additional process. and color.: Dr Gianluigi Barca - Lunar Explorer Italia/Italian Planetary Foundation)55 visitenessun commentoMareKromium
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SOL0003-ML0000010000E1_DXXX-0003ML0000016000E1_DXXX-GB-LXTT-1.jpgGale's Horizon, part I - Sol 3 (an Image Mosaic in RAW Natural Colors; credits for the additional process. and color.: Dr Gianluigi Barca - Lunar Explorer Italia/Italian Planetary Foundation)55 visitenessun commentoMareKromium
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Nereidum_Montes-Dunefield-ESP_029608_1390-PCF-LXTT-IPF-2.jpgDunefield in Nereidum Nontes (EDM - Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga/Lunar Explorer Italia/IPF)55 visiteMars Local Time: 15:43 (Middle Afternoon)
Coord. (centered): 40,495° North Lat. and 309,939° East Long.
Spacecraft altitude: 254,8 Km (such as about 159,3 miles)
Original image scale range: 25,5 cm/pixel (with 1 x 1 binning) so objects ~ 76 cm across are resolved
Map projected scale: 25 cm/pixel
Map projection: EQUIRECTANGULAR
Emission Angle: 1,0°
Phase Angle: 57,3°
Solar Incidence Angle: 56° (meaning that the Sun was about 34° above the Local Horizon at the time the picture was taken)
Solar Longitude: 209,9° (Northern Autumn - Southern Spring)
Credits: NASA/JPL/University of Arizona
Additional process. and coloring: Lunar Explorer ItaliaMareKromium
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SOL0137-4-GB-LXTT-IPF.jpgLooking at Yellowknife Bay - Sol 127 (an Image-Mosaic in Calibrated Natural Colors; credits for the additional process. and color.: Dr Gianluigi Barca/Lunar Explorer Italia/Italian Planetary Foundation)55 visitenessun commentoMareKromium
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Titan-Fensal_and_Aztlan-PIA07732-PCF-LXTT-IPF-1.jpgFensal (EDM - Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga/Lunar Explorer Italia/Italian Planetary Foundation)55 visiteDuring its September 7, 2005, Fly-By of the Saturnian moon Titan, the NASA - Cassini Spacecraft acquired a series of images of a Territory located on the moon's Saturn-facing Hemisphere that were afterwards assembled so to create this small mosaic: once known only as "The H" (because this whole Region looks something like the letter "H", when oriented on its side), the Surface Features visible here now possess provisional names that were assigned to them by the International Astronomical Union (or "IAU", for short).
The Northern Branch of "The H" (shown in this EDM) is now called "Fensal," while the Southern Branch is known as "Aztlan."
Fensal is littered with small "Island-like Landforms" ranging in size from about 5 to 40 Km (such as from approx. 3,1 to a little less than 25 miles) across. These Landforms currently are thought to be Water-Ice Upland Areas (---> kind of small Hills), surrounded by shallower Terrain that is filled-in with dark Particulate Material probably precipitated from the Lower Atmosphere of Titan. In Western Fensal, a few larger Islands can also be seen, like Bazaruto Facula (visible in the upper right corner here and containing what seems to be an Impact Crater or, maybe, a Volcainc Edifice). When viewed in images of Shangri-La (another Titanian Region located on the opposite side of Titan as to Fensal and Aztlan), the Island-like Landforms of this size tend to occur in "clusters" (---> groups) with an apparent so-called "Preferred Orientation" (perhaps due to the action of the Dominant Winds blowing over those Territories). The small Islands found in Fensal, instead, appear much more scattered (and most of them appear roughly circular), although a few Islands do have (show) an East-West orientation to their long axis.
The mosaic is centered at 7° North Latitude and 21° West Longitude on Titan and the frames composing it were taken by the NASA - Cassini Spacecraft Narrow-Angle Camera using a filter sensitive to Wavelengths of Near-InfrarRed Light centered at 938 nanometers. They were acquired at distances ranging from approximately 200.600 to 191.800 Km (such as from about 124.572 to 119.108 miles) from Titan. The Mean Resolution in the images forming the mosaic is about 2 Km (such as 1,242 miles) per pixel.
This picture (which has been cropped from an Original NASA - Cassini Spacecraft b/w image-mosaic published on the NASA - Planetary Photojournal and identified by the n. PIA 07732) has been additionally processed, magnified, contrast enhanced and then colorized, according to an educated guess carried out by Dr Paolo C. Fienga (LXTT-IPF), in Absolute Natural Colors (such as the colors that a human eye would actually perceive if someone were onboard the NASA - Cassini Spacecraft and then looked outside, towards the Saturnian moon Titan), by using an original technique created - and, in time, dramatically improved - by the Lunar Explorer Italia Team. Different colors, as well as different shades of the same color, mean, among others, the existence of different Elements present in the Atmosphere and on the Surface of Titan, each having a different Albedo (---> Reflectivity) and Chemical Composition.
Note: it is possible (but we, as IPF, have no way to be one-hundred-percent sure of such a circumstance), that the actual luminosity of the Clouds and Hazes (as well as the luminosity of the Surface of Titan itself), as seen in this mosaic, would appear, to an average human eye, way lower than it has been shown (or, better yet: interpreted) here.MareKromium
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