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Titan-Clouds-Equatorial_Clouds-PIA12810.jpgTitan's Equatorial Clouds 146 visiteCaption NASA:"NASA's Cassini Spacecraft chronicles the change of Seasons as it captures Clouds concentrated near the Equator of Saturn's largest moon, Titan.
Methane Clouds in the Troposphere, the lowest part of the Atmosphere, appear white here and are mostly near Titan's Equator. The darkest areas are Surface Features that have a low albedo, meaning they do not reflect much light.
Cassini observations of Clouds like these provide evidence of a seasonal shift of Titan's weather systems to low latitudes following the August 2009 Equinox in the Saturnian System (during Equinox, the Sun lies directly over the Equator (see PIA11667 to learn how the Sun's illumination of the Saturnian System changed during the Equinox transition to Spring in the Northern Hemispheres and to Fall in the Southern Hemispheres of the Planet and its moons).
In 2004, during Titan's late Southern Summer, extensive Cloud Systems were common in Titan's South Polar Region (see PIA06110, PIA06124 and PIA06241). Since 2005, Southern Polar Systems have been observed infrequently, and one year after the Equinox, extensive near-equatorial Clouds have been seen.
This image was taken on Oct. 18, 2010, a little more than one Earth year after the Saturnian Equinox, which happens once in roughly 15 Earth years.
The cloud patterns observed from late Southern Summer to early Southern Fall on Titan suggest that Titan's Global Atmospheric Circulation is influenced by both the Atmosphere and the Surface. The temperature of the Surface responds more rapidly to changes in illumination than does the thick Atmosphere. Outbreaks such as the Clouds seen here may be the Titan equivalent of what creates the Earth's tropical rainforest climates, even though the delayed reaction to the change of seasons and the apparently sudden shift is more reminiscent of the behavior over Earth's tropical oceans than over tropical land areas.
A few clouds can be seen in Titan's Southern Latitudes here and some clouds are also visible in the high Northern Latitudes.
This view looks toward the Saturn-facing side of Titan (approx. 5150 Km or 3198,15 miles across). North is up. The image appears slightly grainy because it was re-projected to a scale of about 6 Km (3,726 miles) per pixel. Scale in the original image was approx. 15 Km (9,315 miles) per pixel.
This view consists of an average of three images taken using a filter sensitive to Near-InfraRed Light centered at 938 nanometers, which allows for detection of Titan's Surface and Lower Atmosphere, plus an image taken using a filter sensitive to Visible Light centered at 619 nanometers.
The images were taken with the Cassini spacecraft's narrow-angle camera at a distance of approx. 2,5 MKM (1.552.500 MMs) from Titan and at a Sun-Titan-Spacecraft, or Phase, Angle of 56°".MareKromium
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Titan-Clouds-MF-LXTT.gifExtremely Bright Clouds Formation over Aztlan and Senkyo (a GIF-Movie by Marco Faccin - Lunexit Team)54 visitenessun commentoMareKromium
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Titan-Clouds-N00163811-EB-PCF-LXTT.jpgExtremely bright Cloud-formations in Titan's Upper Atmosphere (Natural Colors; credits for the additional process. and color.: Elisabetta Bonora and Paolo C. Fienga - Lunexit Team)103 visitenessun commentoMareKromium
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Titan-Clouds-Night_Clouds-GIFMovie-W00002325-W00002338.gifNoctilucent Clouds over Titan (GIF-Movie; credits: Dr G. Barca)54 visiteDavvero molto interessanti le deboli Surface Features che si intravedono in questo breve - ma assai suggestivo - GIF-Movie realizzato dal Dr Barca. Sapreste individuarne almeno una?MareKromium
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Titan-Clouds-Noctilucent_Clouds-GIFMovie-N00023443-N00023924.gifNoctilucent Clouds over Titan (GIF-Movie; credits: Dr G. Barca)54 visiteSu Titano è notte, ma come queste immagini (ottimamente montate a formare un GIF-Movie dal nostro Dr Gianluigi Barca) dimostrano piuttosto chiaramente, delle grandi e vaporose formazioni nuvolose passano attraverso gli occhi elettronici di Cassini e si rendono palesi.
Magia delle riprese IR?
No, perchè queste immagini sono state ottenute nello Spettro della Luce Visibile.
E allora, come spiegare la (ripetiamo: EVIDENTE) luminosità delle nuvole di Titano?
Beh, esistono almeno tre modi per provare a spiegare (sensatamente) questo intrigante ed affascinante fenomeno, ma la soluzione (puramente ed assolutamente teorica e speculativa, lo sappiamo) che ci piace privilegiare la potete trovare descritta nell'articolo "Oltre la Nebbia", pubblicato sul nostro Blog "True Planets"...MareKromium
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Titan-Clouds-Noctilucent_Clouds-GIFMovie-N00023501-N00023599.gifNoctilucent Clouds over Titan (GIF-Movie; credits: Dr G. Barca)55 visiteSu Titano è notte, ma come queste immagini (ottimamente montate a formare un GIF-Movie dal nostro Dr Gianluigi Barca) dimostrano piuttosto chiaramente, delle grandi e vaporose formazioni nuvolose passano attraverso gli occhi elettronici di Cassini e si rendono palesi.
Magia delle riprese IR?
No, perchè queste immagini sono state ottenute nello Spettro della Luce Visibile.
E allora, come spiegare la (ripetiamo: EVIDENTE) luminosità delle nuvole di Titano?
Beh, esistono almeno tre modi per provare a spiegare (sensatamente) questo intrigante ed affascinante fenomeno, ma la soluzione (puramente ed assolutamente teorica e speculativa, lo sappiamo) che ci piace privilegiare la potete trovare descritta nell'articolo "Oltre la Nebbia", pubblicato sul nostro Blog "True Planets"...
MareKromium
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Titan-Clouds-North_Polar_Clouds-PIA10434.jpgPolar Clouds on Titan (IR View - False Colors; credits: Lunexit)103 visiteCaption NASA:"Frigid Titan continues to prove itself a remarkably complex and dynamic world. Here, bright clouds are seen encircling the moon's North Polar Region.
The Cassini Spacecraft has revealed the presence of great lakes and seas of liquid hydrocarbons on this part of Titan's surface (see PIA08365 and PIA08930).
An extended, high-altitude haze hovers above the limb of Titan at top of the image.
The image was taken with the Cassini Spacecraft narrow-angle camera on April 26, 2008 using a spectral filter sensitive to wavelengths of Infrared Light centered at 938 nanometers. The view was acquired at a distance of approx. 786.000 Km (such as about 488.000 miles) from Titan.
Image scale is roughly 5 Km (a little more than 3 miles) per pixel".MareKromium
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Titan-Clouds-North_Polar_Clouds-PIA10511.jpgBright Northern Clouds on Titan (natural colors; credits: Lunexit)100 visiteCaption NASA:"Bright clouds circumscribe Titan's North Polar Region: a frigid land of Methane Seas.
The clouds seen in this image and other recent Cassini Spacecraft views are at higher latitudes than similar streak-like clouds observed in the Southern Hemisphere (see PIA08966). Scientists are working to understand why such clouds appear preferentially at certain latitudes on Saturn's largest moon.
While the streaks that grace Titan's Southern Hemisphere are often seen at 40° South Latitude, similar to Wellington, New Zealand, the streaks in the Northern Hemisphere are farther from the Equator, near 56° North Latitude, which is similar to Glasgow, Scotland. North on Titan is up and rotated 16° to the right.
The image was taken with the Cassini spacecraft narrow-angle camera on Sept. 30, 2008 using a spectral filter sensitive to wavelengths of infrared light centered at 938 nanometers. The view was obtained at a distance of approx. 1,2 MKM (such as about (776.000 miles) from Titan and at a Sun-Titan-Spacecraft, or Phase, angle of 71°.
Image scale is 7 Km (about 4,5 miles) per pixel".MareKromium
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Titan-Clouds-North_Polar_Clouds-PIA12812-PCF-LXTT.jpgNorth Polar Clouds (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)157 visiteCaption NASA:"Clouds move above Titan's large Methane Lakes and Seas near the Planet's North Pole. Methane Clouds in the Troposphere, such as the lowest part of the Atmosphere, appear white here and are moving East over several of Titan's large Northern Lakes. The darkest areas are Lakes and Seas of liquid Methane, identifiable because they have a low albedo, meaning they do not reflect much light (the difference in brightness and darkness on the Surface here indicates a difference in its composition).
The clouds seen near Lakes and Seas suggest that Titan may have "Lake-effect" Clouds created by weather systems over large bodies of liquid.
However, without earlier observations to show the Clouds did not originate West of the large Sea "Kraken Mare", scientists cannot determine conclusively if these clouds are really "Lake-effect" Clouds.
If full, Kraken Mare, at about 400.000 square Km (248.400 square miles), would be almost five times the size of North America's Lake Superior.
Even if these Clouds are not directly connected to the Lakes and Seas, scientists think that frequent detections of Clouds at High Northern Latitudes since 2007 are related to the abundant availability of Methane at the Surface in this Region.
This view is centered on Terrain at 49° North Latitude and 179° West Longitude. The North Pole is near the upper right. The Clouds are visible above Terrain at about 60 to 82° North Latitude and 220 to 260° West Longitude. Scientists calculate wind speeds from about 0,5 to about 10 meters per second (such as from about 1 to 22 miles per hour), based on tracking of individual cloud features in different images.
Other Cassini observations of Clouds in Titan's Southern Latitudes provide evidence of a Seasonal Shift of Titan's Weather Systems to low Latitudes from higher, South Polar Latitudes following the August 2009 Equinox in the Saturnian System.
This image was taken with the Cassini Spacecraft narrow-angle camera using a spectral filter sensitive to wavelengths of Near-InfraRed Light centered at 938 nanometers. The view was obtained at a range of distances from approx. 406.000 Km (such as 252.126 miles) to approx. 796.000 Km (such as 494.316 miles) from Titan.
Scale is about 2 Km (1,242 miles) per pixel".MareKromium
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Titan-Clouds-PIA06157.jpgTitan: Mid-Latitude Clouds54 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-PIA06157.jpgTitanian Clouds (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)176 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". MareKromium
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Titan-Clouds-PIA06158.jpgTitanian Clouds (October 2004 fly-by)54 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. Several smaller bright features, between 30 and 200 Km across are seen within the dark terrain. These intriguing features are a focus of further research and observations for Cassini scientists. One clue to their origin and history is the presence of bright "trails" within the dark material on the eastern sides of the bright spots. A mottled texture is seen within Xanadu, including dark, crisscrossing lines, suggestive of tectonic activity. No definitive craters have been found in these images, though several bright rings or circular features are seen in the dark terrain. However, without topographic shading, their identification as impact structures can not be confirmed. The images in this mosaic have been processed to enhance surface features and sharpen boundaries".
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