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Enceladus-EB-LXTT.jpgFountains of Light (High-Def-3D; credits: Elisabetta Bonora - Lunexit Team)55 visitenessun commentoMareKromium
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ESP_016276_2575_RED_abrowse.jpgTranslucent Ice-Patches in the Northern Plains (possible Natural Colors; credits: Dr Paolo C. Fienga - Lunexit Team)55 visitenessun commentoMareKromium
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OPP-SOL2179-PIA12980.jpgThe Rim of Bopulu Crater - Sol 2179 (Approximate True Colors; credits: NASA/JPL-Caltech/Cornell Univ. - Addit. color process.: Dr Paolo C. Fienga - Lunexit Team)55 visiteCaption NASA:"NASA's Mars Exploration Rover used its PanCam to record this view of the Rim of a crater about 65 Km (approx. 40 miles) in the distance, on the South-Western horizon. This Crater, Bopolu, is about 19 Km (approx. 12 miles) in diameter.
The image was taken during the 2179th Martian Day, or Sol, of Opportunity's Mission on Mars (March 11, 2010), two days after the Rover drove Southward away from Concepcion Crater, site of several weeks of investigation.
Opportunity's long-term destination is Endeavour Crater, to the South-East and closer than Bopolu. The intended route heads South before turning East, in order to bypass potentially hazardous Sand Ripples, larger than the ones visible in the foreground of this image.
This Approx. True-Color view combines three exposures taken through filters admitting wavelengths of 750 nanometers, 530 nanometers and 480 nanometers".MareKromium
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OPP-SOL2147-PIA12972.jpgCoating on a Rock standing beside Concepción Crater - Sol 2150 (Natural Colors; credits: Dr Paolo C. Fienga - Lunexit Team) 55 visiteCaption NASA:"This image from the PanCam on NASA's Mars Exploration Rover Opportunity shows a rock called "Chocolate Hills", which the Rover found and examined at the edge of a young crater called "Concepción".
The rover used the tools on its Robotic Arm (RA) to examine the texture and composition of target areas on the rock with and without the dark coating. The rock is about the size of a loaf of bread. Initial analysis was inconclusive about whether the coating on the rock is material that melted during the impact event that dug the Crater.
This view is presented in Natural Color, which makes some differences between materials easier to see. It combines three separate images taken through filters admitting wavelengths of 750 nanometers, 530 nanometers and 430 nanometers. Opportunity took the image during the 2147nd Martian Day, or Sol, of the Rover's Mission on Mars (such as Feb. 6, 2010)".MareKromium
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Titan_and_Rhea-PIA12599.jpgTitanian Encounters...55 visiteCaption NASA:"The moon Rhea moves behind Saturn's largest moon, Titan, in this Mutual Event imaged by the Cassini Spacecraft.
Mutual Event sequences, in which one moon passes close to or in front of another, help scientists refine their understanding of the orbits of Saturn's moons. Part of Rhea's Southern Hemisphere is also visible here through the haze of Titan's Atmosphere.
Titan has been brightened by a factor of 1.5 relative to Rhea. This view looks toward the anti-Saturn side of Titan and the Trailing Hemisphere of Rhea.
The image was taken in Visible green Light with the Cassini spacecraft narrow-angle camera on Nov. 27, 2009. The view was obtained at a distance of approx. 1,2 MKM (about 746.000 miles) from Titan and from about 2,3 MKM (approx. 1,4 MMs) from Rhea.
Image scale in the original image was roughly 14 Km (approx. 9 miles) per pixel on Titan and about 27 Km (approx. 17 miles) per pixel on Rhea. The image has been magnified by a factor of two and contrast-enhanced to aid visibility".MareKromium
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Prometheus.jpgPrometheus55 visitenessun commentoMareKromium
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Mimas-PIA12867.jpgUneven Warmth on Mimas55 visiteThe image shows NASA's Cassini Spacecraft imaging science subsystem Visible-Light mosaic of Mimas from previous flybys on the left. The right-hand image shows the new CIRS temperature data mapped on top of the Visible-Light image.
It has to be underlined the unexpected and bizarre pattern of daytime temperatures found on Saturn's small inner moon Mimas (about 396 Km, or approx. 246 miles, in diameter). The data were obtained by the composite infrared spectrometer (CIRS) on the Cassini Spacecraft during the Spacecraft's closest-ever look at Mimas on Feb. 13, 2010.
The warm part has typical temperatures near 92 Kelvin (minus 294 Fahrenheit), while typical temperatures on the cold part are about 77 Kelvin (minus 320 Fahrenheit). The cold part is probably colder because surface materials there have a greater thermal conductivity, so the Sun's energy soaks into the Sub-surface instead of warming the Surface itself. But why conductivity should vary so dramatically across the Surface of Mimas is a mystery.
The map used to create this image is a mosaic of images taken by Cassini's imaging science subsystem cameras on previous flybys of Mimas. The cold side includes the giant Herschel Crater, which is a few degrees warmer than its surroundings. It's not yet known whether Herschel is responsible in some way for the larger region of cold temperatures that surrounds it.
Cassini took 85 minutes to make the temperature map, as the Spacecraft receded from Mimas. During that time, the distance to Mimas increased from 38.000 to 67.000 Km (such as about 24.000 to 42.000 miles) and the longitude of the center of Mimas' disk increased from 128° West to 161° West, due to the moon's rotation.
Because of this changing geometry, the alignment of the temperatures relative to specific features or coordinates on Mimas is shown only approximately. The temperatures were calculated from the brightness of the moon's infrared heat radiation, measured by CIRS at a wavelength of 12 to 16 microns".MareKromium
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Titan-PIA12843.jpgWhat's inside Titan?55 visiteCaption NASA:"This artist's illustration shows the likely interior structure of Saturn's moon Titan, as deduced from gravity field data collected by the Cassini Spacecraft. The investigation by Cassini's radio science team suggests that Titan's interior is a cool mix of ice studded with rock, though the outermost 500 Km (approx. 300 miles) appear to be ice essentially devoid of any rock.
Many planets and moons, including the Earth, evolve into a body with a clearly distinct rocky core. This radio science investigation suggests Titan's interior, cool and sluggish, failed to allow the interior to separate into completely differentiated layers of ice and rock.
In addition to the Hazy Surface of Titan (yellow), the layers in the cutaway show an ice layer starting near the Surface (light gray), an internal ocean hypothesized from other Cassini data (blue), another layer of ice (light gray) and the mix of rock and ice in the interior (dark gray). In the background are the Cassini Spacecraft and Saturn, not to scale".MareKromium
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Mimas-PIA12572.jpgHerschel Basin (False Colors; credits: NASA/JPL/SSI)55 visitenessun commentoMareKromium
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Mimas-PIA12571.jpgA "hint" of color for Mimas (possible Natural Colors; credits: Dr Paolo C. Fienga - Lunexit Team)55 visitenessun commentoMareKromium
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Mimas-PIA12570.jpgWho are YOU looking at???55 visiteCaption NASA:"This view of Mimas is centered on Terrain located at about 11° South Latitude and 158° West Longitude. North is up.
This view was obtained at a distance of approx. 50.000 Km (approx. 31.000 miles) from Mimas and at a Sun-Mimas-Spacecraft, or Phase, Angle of 17°.
Image scale is roughly 240 meters (790 feet) per pixel".MareKromium
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Mimas-PIA12568.jpgThe "Eye" of Mimas55 visiteCaption NASA:"This mosaic, created from images taken by NASA's Cassini Spacecraft during its closest flyby of Saturn's moon Mimas, looks straight at the moon's huge Herschel Crater and reveals new insights about the moon's Surface. Bright-walled Craters, with Floors and surroundings - about 20% darker than the steep Crater Walls - are notable in this view. Mimas' original Surface, like the surfaces of most of the other major Saturnian moons without Atmospheres, is not pure ice but contains some dark impurities.
Herschel Crater (about 130 Km - approx. 80 miles - wide) and some of the smaller craters seen in this mosaic show relatively dark markings along the lower portion of their walls. Cassini scientists interpret this darkening as evidence for the gradual concentration of impurities from evaporating icy materials in areas where the dark impurities slide slowly down the Crater Wall. There, bright ice is baked away by the Sun and the vacuum of space.
At Herschel, the edge where the Darker Regions contact the Crater Floor, is interrupted by an extensive hummocky area. Scientists believe the hummocky texture came from the flow of melted ice that occurred during the impact that created the Crater itself. That melt filled the bottom of the Crater around the Central Peak.
Dark Streaks are seen making their way down the sides of some craters (marked red in the annotated version), often originating from pockets of dark contaminants embedded just below the rim of the crater wall. The pockets themselves likely represent small, pre-existing, dark-floored craters that were buried by the blanket of material that was thrown out from the newer impact that created the crater rim. The material from a newly exposed dark layer eventually moves downslope and forms a streak. Streaks are sometimes seen starting from the floors of smaller, dark-floored craters perched along Rims of larger Craters.
The interior of Herschel Crater is significantly less cratered than the continuous blanket of ejected material that extends radially outward from its rim. The violent meteor impact that excavated Herschel blasted pulverized debris, including massive chunks of ice, upward. The fallback of this ejected material over the Crater Rim created a thick Debris Blanket and dotted it with Secondary Craters. The presence of a fluid pool of melted material on the Crater Floor, which solidified after the debris fell, probably explains the relative absence of Craters on Herschel's Floor. These are common processes that should occur on bodies without Atmospheres throughout the Solar System. They may be accentuated on Mimas because of the large size of Herschel in comparison to Mimas' size.
Cassini came within about 9500 Km (approx. 5900 miles) of Mimas during its flyby on Feb. 13, 2010. This mosaic was created from 7 images taken that day in Visible Light with Cassini's narrow-angle camera. An eighth image, taken with the wide-angle camera on the same flyby, is used to fill in the lower right of the mosaic. The images were re-projected into an orthographic map projection. This view looks toward the Leading Hemisphere of Mimas.
This view is centered on terrain at about 10° South Latitude and 125° West Longitude. North is up.
The view was obtained at a distance of approx. 30.000 Km (about 19.000 miles) from Mimas and at a Sun-Mimas-Spacecraft, or Phase, Angle of 27°.
Image scale is roughly 180 meters (600 feet) per pixel".MareKromium
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