| Piú viste - Titan: The "Foggy" Moon |
Titan-Clouds-MF-LXTT.gifExtremely Bright Clouds Formation over Aztlan and Senkyo (a GIF-Movie by Marco Faccin - Lunexit Team)58 visitenessun commentoMareKromium
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Titan-W00064419-20-21-28-29-30-MF-LXTT.jpgBeyond the Fog... (False Colors; credits for the additional process. and color.: Dr Marco Faccin - Lunexit Team)58 visitenessun commentoMareKromium
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Titan-Lakes-Ontario_Lacus-01-PIA13173.jpgOntario Lacus58 visiteThis is Ontario Lacus, the largest lake on the Southern Hemisphere of Saturn's moon Titan. It is based on overlapping radar images obtained by NASA's Cassini Spacecraft on June 22, 2009, July 8, 2009 and Jan. 12, 2010. The images were synthesized into stereoscopic images by the Cassini radar team.
The Northern Shoreline features low Hills, probably about 1 Km (3000 feet) in altitude, and flooded River Valleys. A smooth, wave-sculpted Shoreline, like that seen on the South-Eastern side of Lake Michigan, can be seen on the North-Eastern side of the Lake.
The South-Eastern shore features a round-headed bay intruding into the shore. The middle part of the Western Shoreline shows the first well-developed delta observed on Titan.
Topography has been vertically exaggerated by a factor of roughly 10 times. Titan's solid Surface and Atmosphere are portrayed in shades of brown, approximating their appearance as measured by the descent imager and spectral radiometer on board the Huygens probe, which landed on Titan in 2005. Scientists surmise the liquid Methane, ethane and propane in the lake would look black to the human eye, but this is a hypothesis based on the best available data.
The Sun was placed low on the horizon, at an angle similar to where it was during the Cassini Fly-Bys.MareKromium
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Titan-N00156684-85-86-MF-LXTT.jpgWatching through the Fog... (False Colors; credits for the additional process. and color.: Dr Marco Faccin - Lunexit Team)58 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)58 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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Titan-N00023130.jpgTitan57 visiteDue immagini di Titano, riprese da una distanza di circa 1,5 milioni di Km. Alcune caratteristiche superficiali di Titano incominciano a distinguersi con una certa chiarezza ed il giorno del "contatto" si avvicina. Certo è che, ancora oggi, fra le tante lune di Saturno, Titano, perennemente avvolto in una spessa coltre di nuvole di colore giallastro, sembra essere davvero la più enigmatica. Se la Sonda Huygens sarà fortunata, forse riusciremo a vedere ed a scoprire qualcosa. Titano ci sta aspettando...
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Titan-Close Up 1.jpgTitan's fly-by "A" - Close-up 157 visiteLe primissime immagini del Passaggio Ravvicinato (fly-by) "A" della Sonda Cassini-Huygens accanto a Titano. Non abbiamo i dati telemetrici relativi a questa immagine, ma certamente siamo ancora molto lontani dal punto di maggior vicinanza fra i due corpi (in questo momento ci troviamo, probabilmente, fra i 400 ed i 500.000 Km di distanza da Titano). Il "passaggio radente" (si fa per dire...) di Cassini-Huygens accanto a Titano per questo primo fly-by (contraddistinto dalla lettera "A") avverrà con il transito della Sonda ad una distanza di circa 1.200/1.300 Km dalla "Luna Nebbiosa" (Hazy-Moon). Un "niente", effettivamente, laddove paragonato alle distanze che Cassini-Huygens ha coperto (e sta ancora coprendo) per fare questa "passeggiata" nel Regno di Saturno...
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Titan-PIA06122_modest.jpgTitan from about 1.000.000 Km (true colors)57 visiteUn'immagine davvero molto ben definita in cui si può distinguere nettamente, nonostante la distanza della Sonda dal Pianeta sia ancora considerevole, la particolare tessitura (oltre al colore davvero curioso - grigio/viola?) degli strati alti dell'atmosfera di Titano.
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Titan-Undefined_Surface_Features-Radar_View-PIA06995_modest.jpgAnother "radar view" from Titan: the "arrow"57 visiteOccorre la Caption NASA originale per tentare di capire qualcosa di questa "oscura" (da tutti i punti di vista) immagine radar di Titano: "...the (arrow-like) "feature" is approximately 30 Km across and it is formed from 2 straight lines that intersect. Looking more closely, one can distinguish other linear features that seem to follow the left side of the "arrow" and perhaps interact in some way with a dark spot. Straight lines may represent fractures or faults in the icy crust, or they may form from material that has flowed or has been shaped by wind, either recently or in the distant past.
The area shown is about 115 Km wide and 170 Km high and is located near 52° North latitude and 73° West longitude. This radar image is part of a larger strip of data acquired on Oct. 26, 2004, as Cassini passed Titan at a distance of 1.200 Km".
Secondo noi il rilievo che alla NASA chiamano "freccia" potrebbe essere una sorta di ciglio roccioso ma, come vedete Voi stessi, con un'immagine così...ogni ipotesi è buona!
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Titan-PIA06151_modest.jpgTitan from about 810.000 Km57 visiteCaption NASA originale:"The bright and dark regions near the center of the frame are features on Titan's surface. The image has been processed to make features more visible. The surface contrast is degraded toward the edges of the disk due to the effects of Titan's smoggy atmosphere. The region seen here is similar to that seen during Cassini's first close flyby of Titan in October. The bright area toward the bottom of the image is the region dubbed "Xanadu." North is to the upper right.
The image was acquired at a distance of approximately 810.000 Km and the image scale is 4.8 Km per pixel". Ed ora una curiosità: guardate il bordo di Titano, in alto alla Vostra Dx, ad ore 2, c'è un rilievo rotondeggiante (una "cupola scura") perfettamente visibile. Non sembra un difetto della foto o un artifact derivante da vizio di processo e/o di compressione dell'immagine. E allora, secondo Voi, che cos'è?
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Titan-Clouds-PIA06157.jpgTitan: Mid-Latitude Clouds57 visiteCaption NASA originale:"The Clouds seen here are at about 38° South Latitude on Titan. The Clouds across the middle of the frame extend about 250 Km (approx. 155 miles). The image scale is about 0,6 Km (approx. 0,4 miles) per pixel".
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Titan-Clouds-PIA06159.jpgTitanian Clouds (December 2004 fly-by)57 visiteCaption NASA originale:"Cutting through the middle of the image is a sharp boundary between the bright region known as Xanadu Regio on the right and dark terrain to the left. This mosaic includes some areas seen at regional scales in October 2004 (see PIA 06124), as well as additional areas to the north and east not seen during that flyby. Among the new features seen in this mosaic is a strangely shaped bright feature near the center of the image as well as clouds near the bottom of the image (see also PIA 06110). The northern portion of the bright/dark boundary appears to be more complex than the arching and sharp boundary seen farther to the south. Cassini scientists continue to examine images such as this to determine the cause of this terrain. The images in this mosaic have been processed to enhance surface features and sharpen brightness variations".
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