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Saturn-PIA14119.jpgLarge Ammonia Crystals in Saturn Storm (False Colors; credits: NASA/JPL-University of Arizona)69 visiteCaption NASA:"This false-color InfraRed image, obtained by NASA's Cassini Spacecraft, shows clouds of large Ammonia ice particles dredged up by a powerful storm in Saturn's Northern Hemisphere. Large updrafts dragged Ammonia gas upward more than 30 miles (approx. 50 Km) from below. The Ammonia then condensed into large crystals in the frigid Upper Atmosphere. This storm is the most violent ever observed at Saturn by an orbiting Spacecraft.
Cassini's Visual and InfraRed Mapping Spectrometer obtained these images on Feb. 24, 2011. Scientists colorized the image by assigning red to brightness detected from the 4.08-micron wavelength, green to brightness from the 0.90-micron wavelength, and blue to brightness from the 2.73-micron wavelength. Large particles (red) reflect Sunlight well at 4.08 microns. Particles at high altitude (green) reflect Sunlight well at 0.9 microns. Particles comprised of Ammonia -- especially large ones -- do not reflect 2.73-micron sunlight well, but instead absorb light at this wavelength.
The storm here shows up as yellow, demonstrating that it has a large signal in both red and green colors. This indicates the cloud has large particles and extends upward to relatively high altitude. In addition, the lack of blue in the feature indicates that the storm cloud has a substantial component of Ammonia Crystals. The head of the storm is particularly rich in such particles, as created by powerful updrafts of Ammonia gas from depth in the throes of Saturn's thunderstorm".MareKromium
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SOL1388-2P249497680EFFAWNSP2552R6M1-PCF-LXTT.jpgDeep Rover Tracks - Sol 1388 (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)69 visitenessun commentoMareKromium
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ZZ-Mercury-Limb-PIA14250-PCF-LXTT-1.jpgCrescent Mercury (Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)69 visiteMercury forms a beautiful crescent shape in this image, acquired as the MESSENGER Spacecraft was high above Mercury's Southern Hemisphere. On the left side is the Terminator, dividing the day from night. On the right side is the sunlit Limb, separating Mercury from the darkness of (the Inner) Space.
This image was acquired as part of MDIS's limb imaging campaign. Once per week, MDIS captures images of Mercury's Limb, with an emphasis on imaging the Southern Hemisphere Limb. These Limb images provide information about Mercury's shape and complement measurements of topography made by the Mercury Laser Altimeter (MLA) of Mercury's Northern Hemisphere.
On March 17, 2011 (March 18, 2011, UTC), MESSENGER became the first Spacecraft ever to orbit the planet Mercury. The mission is currently in its commissioning phase, during which Spacecraft and instrument performance are verified through a series of specially designed checkout activities. In the course of the one-year primary mission, the Spacecraft's 7 scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost Planet.
Date acquired: May, 24th, 2011
Image Mission Elapsed Time (MET): 214697006
Image ID: 290397
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filter: 7 (748 nanometers)
Center Latitude: 53,01° South
Center Longitude: 116,7° East
Resolution: 2827 meters/pixel
Scale: Mercury's radius is about 2440 Km (approx. 1520 miles)MareKromium
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Saturn-PIA12825.jpgSaturnian Storm (False Colors; credits: NASA/JPL-Caltech/Space Science Institute)69 visiteCaption NASA:"These false-color images from NASA's Cassini Spacecraft chronicle a day in the life of a huge storm that developed from a small spot that appeared 12 weeks earlier in Saturn's Northern Mid-Latitudes.
This storm is the largest and most intense observed on Saturn by NASA's Voyager or Cassini Spacecraft. The storm is still active. As seen in these and other Cassini images, the storm encircles the Planet - whose circumference at these latitudes is approx. 186.000 miles (about 300.000 Km).
From North to South, it covers a distance of about 9000 miles (approx. 15.000 Km), which is one-third of the way around the Earth. It encompasses an area of about 1,5 BSMs (Billion Square Miles - such as approx. 4 BSKM), or eight times the surface area of Earth. This storm is about 500 times the area of the biggest of the Southern Hemisphere storms observed by Cassini.
The highest clouds in the image are probably around 100 millibars pressure, or 60 miles (approx. 100 Km) above the regular undisturbed clouds. These false colors show clouds at different altitudes. Clouds that appear blue here are the highest and are semitransparent, or optically thin. Those that are yellow and white are optically thick clouds at high altitudes. Those shown green are intermediate clouds. Red and brown colors are clouds at low altitude unobscured by high clouds, and the deep blue color is a thin haze with no clouds below. The base of the clouds, where lightning is generated, is probably in the water cloud layer of Saturn's Atmosphere. The storm clouds are likely made out of Water Ice covered by crystallized Ammonia.
Taken about 11 hours -- or one Saturn day -- apart, the two mosaics in the lower half of this image product consist of 84 images each. The mosaic in the middle was taken earlier than the mosaic at the bottom. Both mosaics were captured on Feb. 26, 2011, and each of the two batches of images was taken over about 4,5 hours.
Two enlargements from the earlier, middle mosaic are shown at the top of this product. The white lines below the middle mosaic identify those parts of the mosaic that were enlarged for these close-up views. The enlargement on the top left shows the head of the storm, and that on the top right shows the turbulent middle of the storm. Cassini observations have shown the head of the storm drifting West at a rate of about 2,8° of Longitude each Earth day (28 meters per second, or 63 miles per hour). The central latitude of the storm is the site of a Westward jet, which means that the clouds to the North and South are drifting Westward more slowly or even drifting eastward. In contrast, clouds at Saturn's Equator drift Eastward at speeds up to 450 meters per second (about 1000 miles per hour).
Both of the long mosaics cover an area ranging from about 30° to 51° North Latitude. The views stretch from about 138° (on the left) to 347° West Longitude (on the right), passing through 360/0° West Longitude near the far right of the mosaics.
The images were taken with the Cassini Spacecraft narrow-angle camera using a combination of spectral filters sensitive to wavelengths of Near-InfraRed light. The images filtered at 889 nanometers are projected as blue. The images filtered at 727 nanometers are projected as green, and images filtered at 750 nanometers are projected as red.
The views were acquired at a distance of approx. 1,5 MMs (such as about 2,4 MKM) from Saturn and at a Sun-Saturn-Spacecraft Angle (i.e.: Phase Angle) of 62°. Both the top and bottom images are simple cylindrical map projections, defined such that a square pixel subtends equal intervals of Latitude and Longitude. At higher Latitudes, the pixel size in the North-South direction remains the same, but the pixel size in the East-West direction becomes smaller. The pixel size is set at the Equator, where the distances along the sides are equal. The images of the long mosaics have a pixel size of 33 miles (53,108 Km) at the Equator, and the two close-up views have a pixel size of 6 miles (9,656 Km) per pixel at the equator".MareKromium
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Saturn-PIA12824.jpgSaturnian Storm (Natural Colors; credits: NASA/JPL-Caltech/Space Science Institute)69 visiteCaption NASA:"The huge storm churning through the Atmosphere in Saturn's Northern Hemisphere overtakes itself as it encircles the Planet in this Natural Colors view from NASA's Cassini Spacecraft.
This picture, captured on Feb. 25, 2011, was taken about 12 weeks after the storm began, and the clouds by this time had formed a tail that wrapped around the Planet. Some of the clouds moved south and got caught up in a current that flows to the East (to the right) relative to the storm head. This tail, which appears as slightly blue clouds South and West (left) of the storm head, can be seen encountering the storm head in this view.
This storm is the largest, most intense storm observed on Saturn by NASA's Voyager or Cassini Spacecraft. It is still active today. As scientists have tracked this storm over several months, they have found it covers 500 times the area of the largest of the Southern Hemisphere storms observed earlier in the Cassini Mission (see PIA06197).
The shadow cast by Saturn's Rings has a strong seasonal effect, and it is possible that the switch to powerful storms now being located in the Northern Hemisphere is related to the change of seasons after the Planet's August 2009 Equinox.
Huge storms called Great White Spots have been observed in previous Saturnian years (each of which is about 30 Earth years), usually appearing in late Northern Summer. Saturn is now experiencing early Northern Spring, so this storm, if it is a Great White Spot, is happening earlier than usual. This storm is about as large as the largest of the Great White Spots, which also encircled the planet but had latitudinal sizes ranging up to approx. 20.000 Km (roughly 12.000 miles). The Voyager and Cassini Spacecrafts were not at Saturn for previous Great White Spot appearances.
The storm is a prodigious source of radio noise, which comes from lightning deep in the Planet's Atmosphere. The lightning is produced in the water clouds, where falling rain and hail generate electricity. The mystery is why Saturn stores energy for decades and releases it all at once. This behavior is unlike that at Jupiter and Earth, which have numerous storms going on at all times.
This view looks toward the sunlit side of the Rings from just above the Ring-Plane. Images taken using red, green and blue spectral filters were combined to create this Natural Color view. The images were acquired with the Cassini Spacecraft wide-angle camera at a distance of approx. 1,4 MMs (such as about 2,2 MKM) from Saturn. Image scale is roughly 80 miles (128,7472 Km) per pixel".MareKromium
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SOL0003-ML0000034000E1_DXXX-0003ML0000039000E1_DXXX-GB-PCF-LXTT-2.jpgGale's Horizon, part II - Sol 3 (an Image Mosaic in Calibrated Natural Colors; credits for the additional process. and color.: Dr Gianluigi Barca - Lunar Explorer Italia/Italian Planetary Foundation)69 visitenessun commentoMareKromium
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ZZ-Mercury-Craters-Mena_and_Cezanne_Crater-PIA16341-PCF-LXTT-IPF.jpgMena and Cezanne Crater (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga/Lunar Explorer Italia/Italian Planetary Foundation)69 visiteIn this Image-Mosaic, the Bright Rays of Mena Crater and the distinctive color difference of Cezanne Crater (with the surrounding area) are well highlighted. These two distinctive Impact Features provide beautiful contrast to this Absolute Natural Color image, giving the viewer more insight into reflectance variations (---> Albedoes) on Mercury's Surface. Also note the extremely old, degraded and larger, infilled Unnamed Crater visible on the center right of the frame, which is crossed by at least three major Crater Chains.
Date acquired: June 04, 2012
Image Mission Elapsed Time (MET): 247336883, 247336875, 247336879
Image ID: 1955368, 1955366, 1955367
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filters: 9, 7, 6 (996, 748, 433 nanometers) in red, green, and blue
Center Latitude: 3,78° South
Center Longitude: 235,8° East
Resolution: 552 meters/pixel
Scale: Cezanne Crater, such as the Crater in the bottom center, is about 67 km (approx. 41 miles) in diameter.
Solar Incidence Angle: 55,6° (meaning that the Sun was about 34,4° above the imaged Local Horizon at the time the pictures were taken)
Emission Angle: 0,0° (meaning that the MESSENGER Spacecraft, at the time that the pictures were taken, was absolutely perpendicular to the Mercurian Surface visible in the center of the frame)
Sun-Mercury-MESSENGER (or "Phase") Angle: 55,6°MareKromium
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ZZ-Mercury-Craters-Rachmaninoff_Crater-PIA16399-PCF-LXTT-IPF.jpgFeatures of Rachmaninoff Cratrer (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga/Lunar Explorer Italia/Italian Planetary Foundation)69 visiteRachmaninoff is a spectacular Double-Ring Impact Basin on Mercury, and this Absolute Natural Color view of it, is one of the highest resolution color image sets acquired of the Basin's Floor. Visible around the edges of the frame is a circle of Mountains that make up Rachmaninoff's Peak-Ring Structure, which surrounds concentric Troughs located on the on the Basin Floor. The color of the Basin's Floor inside the Peak-Ring differs from the darker material outside of it, as can also be seen in other images of this Feature.
Date acquired: July 31, 2012
Image Mission Elapsed Time (MET): 252265403, 252265399, 252265395
Image ID: 2305612, 2305611, 2305610
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filters: 9, 7, 6 (996, 748, 433 nanometers) in red, green, and blue
Center Latitude: 27,64° North
Center Longitude: 57,58° East
Resolution: 149 meters/pixel
Scale: Rachmaninoff's Inner Ring is approximately 140 Km (about 87 miles) in diameter
Solar Incidence Angle: 39,7° (meaning that the Sun was about 50,3° above the imaged Local Horizon at the time that the picture was taken)
Emission Angle: 19,2°
Sun-Mercury-MESSENGER (or "Phase") Angle: 59,0°MareKromium
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Craters-Trouvelot_Crater-PIA16641-PCF-LXTT-IPF.jpgThe Dunefield inside Trouvelot Crater (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga/Lunar Explorer Italia/Italian Planetary Foundation)69 visiteOrbit Number: 47874
Latitude (centered): 16,1118° North
Longitude (East): 346,733°
Instrument: VIS
Captured: September, 29th, 2012MareKromium
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SOL0136-2-GB-LXTT-IPF.jpgHorizon, from Yellowknife Bay - Sol 135 (an Image-Mosaic in Slightly Saturated Natural Colors; credits for the additional process. and color.: Dr Gianluigi Barca/Lunar Explorer Italia/Italian Planetary Foundation) 69 visitenessun commentoMareKromium
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SOL0141-1-GB-LXTT-IPF~0.jpgThe "Paving" of Yellowknife Bay - Sol 141 (an Image-Mosaic in slightly Saturated Natural Colors; credits for the additional process. and color.: Dr Gianluigi Barca/Lunar Explorer Italia/Italian Planetary Foundation)69 visitenessun commentoMareKromium
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ZZ-Mercury-Craters-Unnamed_Crater-PIA17290-PCF-LXTT-IPF-1.jpgUnnamed and (relatively) Fresh Impact Crater (EDM - Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga/Lunar Explorer Italia/Italian Planetary Foundation)69 visiteThis Absolute Natural Color Image-Mosaic shows us a bright (and, of course, relatively speaking, "fresh") Complex Mercurian Impact Crater - approx. 33 Km (such as about 20,49 miles) in diameter - that exhibits Terraced and Multi-Layered Inner Walls and Slopes - with some Collapse Feature (Mass-Wasting?) here and there -, an also quite Complex Central Peaks' System and, last but not least, the (more than just) possible evidence of a large Pyroclastic Deposit located on it's Eastern Side (---> Dx of the Crater for the Observer), and mostly concentrated in the Region going from about 1 to 4 o'clock of its Outer Surroundings.
Date acquired: November, 6th, 2011
Images Mission Elapsed Time (MET): 229105596, 229105592, 229105588
Images ID: 980566, 980565, 980564
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 25,42° North
Center Longitude: 266,80° East
Solar Incidence Angle: 52,3° (meaning that the Sun, at the time that the picture was taken, was about 37,7° above the imaged Local Mercurian Horizon)
Emission Angle: 16,8°
Sun-Mercury-Messenger (or "Phase") Angle: 69,1°
This picture (which is a crop from an Original NASA - MESSENGER Spacecraft's false colors Map-Projected image-mosaic published on the NASA - Planetary Photojournal with the ID n. PIA 17290) has been additionally processed, contrast enhanced, magnified and then re-colorized in Absolute Natural Colors (such as the colors that a human eye would actually perceive if someone were onboard the NASA - MESSENGER Spacecraft and then looked down, towards the Surface of Mercury), 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 other things, the existence of different Elements (Minerals) present on the Surface of Mercury, each having a different Albedo (---> Reflectivity) and Chemical Composition.MareKromium
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