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| Piú viste - Titan: The "Foggy" Moon |
Titan-PIA14626-PCF-LXTT-IPF.jpgAt Titan's Poles (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunar Explorer Italia/Italian Planetary Foundation) 70 visiteTitan's South Polar Vortex seems to "float" above the moon's South Pole in this NASA - Cassini Spacecraft view. The Vortex, which is a mass of gases swirling around the South Pole, high in the moon's Atmosphere, can be easily seen in the lower right of this view. On the other hand, Titan's Northern "Hood" is also well visible, since it covers almost all the Northern Regions of this always mysterious and fascinating Saturnian moon. This view looks toward the Leading Hemisphere of Titan (which is approx. 3200 miles, or about 5150 kilometers across). North on Titan is up and rotated 25° to the left.
The image was taken with the NASA - Cassini Spacecraft Narrow-Angle Camera on July 6, 2012, using a Spectral Filter sensitive to wavelengths of Near-InfraRed light, centered at 889 nanometers. The view was acquired at a distance of approximately 1,7 Million Miles (such as about 2,8 Million Kilometers) from Titan and at a Sun-Titan-Spacecraft, or Phase, Angle of 86°. Scale in the original image was about 11 miles (such as approx. 17 Km) per pixel. Afterwards, the image has been contrast enhanced and magnified, so to improve the visibility of the most interesting Features existing in the Titanian Atmosphere.
This picture (which is an Original NASA - Cassini Spacecraft frame published on the NASA - Planetary Photojournal with the ID n. PIA 14626) has been additionally processed and then colorized, according to an informed speculation 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 of Titan, each having a different Albedo (---> Reflectivity) and Chemical Composition.MareKromium
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Titan-Lakes-Ontario_Lacus-00-PIA13172.jpgOntario Lacus69 visiteThis image of Ontario Lacus, the largest lake on the Southern Hemisphere of Saturn's moon Titan, was obtained by NASA's Cassini Spacecraft on Jan. 12, 2010.
North is up in this image. Objects appear bright in this radar image when they are tilted toward the Spacecraft or have rough surfaces. The lake surface appears dark because it is smooth. The Northern Shoreline features flooded River Valleys and Hills as high as about 1 Km (3000 feet).
A smooth, wave-sculpted Shoreline, like that seen on the S/Eastern side of Lake Michigan, can here be seen on the N/Eastern side of the lake.
Smooth lines parallel to the current shoreline could be formed by low waves over time, which were likely driven by winds sweeping in from the West or South-West.
The S/Eastern shore features a round-headed Bay intruding into the shore. The liquid-filled depressions appear to be relatively recent.
The middle part of the Western Shoreline shows the first well-developed Delta observed on Titan. The shape of the Delta shows that liquid flowing down from a higher plain has switched Channels on its way into the Lake, forming at least two lobes. Examples of this kind of Channel switching and wave-modified deltas can be found on Earth at the Southern end of Lake Albert between Uganda and the Democratic Republic of Congo in Africa and the remains of an ancient lake known as Megachad in the African country Chad.
Titan is the only other world in our Solar System known to have standing bodies of liquid on its Surface. Because Surface temperatures at the Poles average a chilly 90 Kelvin (about minus 300 degrees Fahrenheit), the liquid is a combination of Methane, Ethane and Propane, rather than water.
Ontario Lacus has a surface area of about 15.000 square Km (approx. 6000 square miles), slightly smaller than its terrestrial namesake, Lake Ontario.MareKromium
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Titan-MF-EB-LXTT-02.jpgNot an Aurora! (a GIF-Movie by Elisabetta Bonora and Marco Faccin - Lunar Explorer Italia/IPF)69 visiteUn suggerimento: mentre osservate la "nuvola" (quale che ne sia la natura) che ruota lentamente attorno al Polo Sud di Titano, provate a guardare anche il bordo (---> limb) del Corpo Celeste in oggetto e, in particolare, osservate le variazioni (a nostro parere eclatanti) della sua Coltre Atmosferica Alta. Potrebbe esistere una correlazione tra simili variazioni e l'Evento Anomalo Sud-Polare? Oppure le variazioni di consistenza, texture e luminosità della Coltre Atmosferica Alta di Titano sono solo un effetto ottico derivante dal cambio di Angolo di Fase (e cioè l'Angolo esitente tra il Sole, Titano e la Sonda CASSINI) ed evidenziato in forma curiosamente eclatante dal montaggio dei diversi frames che vanno a comporre il filmato GIF? Domande, domande, domande.....MareKromium
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Titan-N00199279-84-False_and_Natural_Color-EB-MF-LXTT-IPF.jpgVisions of Titan (Superdefinition, False Colors - Left-Sx - Calibrated Natural Colors - Right-Dx -; credits for the additional process. and color.: Elisabetta Bonora and Marco Faccin/Lunar Explorer Italia/Italian Planetary Foundation) 69 visitenessun commentoMareKromium
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Titan-W00012609.jpgHidden Land, strange "clouds"...68 visiteOriginal caption:"W00012609.jpg was taken on December 26, 2005 and received on Earth December 27, 2005. The camera was pointing toward TITAN at approximately 38,016 kilometers away, and the image was taken using the CB3 and CL2 filters. This image has not been validated or calibrated".
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Titan-PIA08733.jpgCrescent Titan (HR)68 visiteCaption NASA originale:"This composite image, composed of two images taken with Cassini's Visual and Infrared Mapping Spectrometer (VIMS), shows a crescent view of Saturn's moon Titan.
The data were obtained during a flyby on July 22, 2006, at a distance of 15.700 Km (about 9.700 miles) from Titan. The image was constructed from images taken at wavelengths of 1,26 microns (blue), 2 microns (green) and 5 microns (red)".
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Titan-Regions-Aztlan,_Fensal_and_Senkyo_Region-PIA12655-PCF-LXTT2.jpgAztlan, Fensal and Senkyo Region (Natural Colors; credits: Dr Paolo C. Fienga - Lunexit Team)68 visiteNota Lunexit: questa colorizzazione è stata INTEGRALMENTE ottenuta mediante l'impiego di Illuminazione Virtuale.MareKromium
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Titan-W00002390.jpgThe "Dark Side" of Titan from about 107.000 Km67 visiteLa Sonda Cassini-Huygens è passata accanto a Titano ed ora se ne sta rapidamente allontanando. Questa immagine è stata ripresa quando Titano era già stato superato di oltre 100.000 Km. Si tratta, come potete intuire, di una ripresa del lato di Titano immerso nella notte, mentre la luce che emerge dal bordo del Pianeta - formando una sorta di "aureola" - è causata dai raggi del Sole che passano attraverso gli strati superiori della sua atmosfera, generando un curioso fenomeno di diffusione luminosa.
Questo tipo di immagine, oltre ad essere piuttosto suggestiva, ci permette anche di vedere abbastanza bene i vari sub-strati in cui si suddivide (o sembra suddividersi...) l'atmosfera di Titano.
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Titan_and_Mimas-EB-LXTT.jpgDo dimensions count? (an Image-Mosaic in Natural Colors by Elisabetta Bonora - Lunexit Team)67 visitenessun commentoMareKromium
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Titan-CB3-CB2-MT3-EB-LXTT.jpgTechnicolored Titan (False Colors; credits for the additional process. and color.: Elisabetta Bonora - Lunexit Team)67 visitenessun commentoMareKromium
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Titan-PIA16635-PCF-LXTT-IPF-1.jpgTitanian Northern Lakes (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga/Lunar Explorer Italia/Italian Planetary Foundation)67 visiteThe Lakes existing on the Saturnian moon Titan, reflect Radio Waves in varying ways, as it can be noticed in this Radio-Image obtained by the the NASA - Cassini Spacecraft. Scientists think the variations in Reflectivity, or Brightness, have to be related with the smoothness (such as the so-called "texture") of the imaged Surface. However, if a Lake is fully liquid, it always looks VERY dark (actually black); but if it is only partially liquid, then it looks a lot brighter. In this frame, taken from Titan's High Northern Latitudes (such as at approx. 79° North Latitude and 58° West Longitude) on May, 22, 2012, the Lakes located on on the left (Sx) side of it are full of Liquid Hydrocarbons, while the ones - barely visible - located on the top right (Dx) of the picture are only partially filled - it has to be said, however, that what can be seen on the right side of the frame, could even be the representation of simple Saturated Ground (---> a Surface Feature - or, better yet, a Surface "Condition" - known as "Mudflat" ---> Mudflats or Mud Flats, also known as Tidal Flats, are Coastal Wetlands that form when huge quantities of Mud are deposited by the action of Oceanic Tides or particularly fast-flowing Rivers).
The Lakes visible in this image are each about 35 to 45 Km (such as approx. 22 to 30 miles) across, or about the size of Lake Tahoe, on the California-Nevada Border. Some of the differences in Reflectivity could also be explained by the presence, in the Lakes, of floating blocks of Hydrocarbon Ice. The image was obtained by the Cassini Radar Mapper at a scale of about 350 meters (1100 feet) per pixel.
This frame (which is a crop obtained by an Original NASA - CASSINI Spacecraft Radio-Image published on the NASA - Planetary Photojournal with the n. PIA 16635), since it is just a Radio-Image of the Titanian Surface and NOT a real view of it, has been colorized, according to an educated guess, by Dr Paolo C. Fienga (LXTT-IPF), in what they could reasonably be its possible Absolute Natural Colors (such as the colors that a human eye would perceive if someone were onboard the NASA - CASSINI Spacecraft and, once the thick layer of Titanian Hazes and Fogs shall have been completely overcome, looked down, towards the Surface of Titan itself), by using an original technique created - and, in time, dramatically improved - by the Lunar Explorer Italia Team.MareKromium
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Titan-PIA08945.jpgA new "Ortographic View" of Titan66 visiteBright and dark terrains on Titan's Trailing Hemisphere are revealed by Cassini's Imaging Science Subsystem in this mosaic of images taken during the T28 flyby in April 2007. The Region shown in this image, centered on the northern part of Titan's Trailing Hemisphere (near 31,2° North and 220,7° West), had only been seen at very low resolution until February 2007, when Cassini flew over this area for the first time. This mosaic consists of images taken during one of a series of flybys in early 2007 designed to study this long unavailable part of Titan.
Several intriguing surface features can be seen in this mosaic that warrant further study. Along the top of the mosaic is a series of dark lineaments, or linear features, that stand out against the blandness of the Northern, Mid-Latitude Terrain.
These features were also observed by the RADAR instrument in December 2006 and represent an area of potential future co-analysis for the RADAR and camera teams. Another such region is the large bright area known as Adiri at bottom center, also imaged by RADAR in October 2005.
The mosaic shows a number of dark areas within Adiri Regio that line up with small dune fields observed by RADAR. A portion of the dark terrain surrounding Adiri was also observed in 2005 by RADAR, and likewise was found to consist of large stretches of longitudinal dune fields - further supporting the correlation between equatorial dark regions and dune "seas".
To the East of Adiri is a dark spot surrounded by a ring of bright material, which may be associated with an impact crater similar to Sinlap, discovered earlier in the Cassini mission (see PIA6222).
This mosaic consists of 29 separate frames using a total of 116 images.
Each frame consists of three images, taken using a filter sensitive to near-infrared light centered at 938 nanometers, allowing for observations of Titan's surface and lower atmosphere, added together. An image taken using a filter sensitive to visible light centered at 619 nanometers was then subtracted from the product, effectively removing the lower atmosphere contribution to the brightness values in the image, increasing image contrast and improving the visibility of surface features.
This process is also intended to reduce noise, but some camera artifacts still remain, such as a dark ring caused by dust in the camera system near the bottom right of each frame.
The images used for this mosaic were taken on April 11, 2007 from distances ranging from approx. 106.000 to 180.000 Km (such as from about 66.000 to 112.000 miles).
This mosaic is in an orthographic view of Titan (an orthographic view is most like the view seen by a distant observer looking through a telescope).
MareKromium
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