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Titan-Clouds-Noctilucent_Clouds-GIFMovie-N00023443-N00023924.gifNoctilucent Clouds over Titan (GIF-Movie; credits: Dr G. Barca)56 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-Night_Clouds-GIFMovie-W00002325-W00002338.gifNoctilucent Clouds over Titan (GIF-Movie; credits: Dr G. Barca)56 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-Cloud_System-GIFMovie-W00002371-W00002379.gifThe complex Titanian Cloud-System (GIF-Movie; credits: Dr G. Barca)56 visiteLe formazioni nuvolose di Titano? Semplicemente IMPONENTI!...MareKromium
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Titan-Dunes-PIA11802.jpgAt the Edge of Titan's Dunes56 visiteThis is a portion of a Cassini Radar Mapper image obtained by the Cassini Spacecraft on its Dec. 21, 2008, flyby of Saturn's moon Titan.
The area shown covers the southern boundary of an equatorial band where longitudinal dunes (dunes that form along the wind direction) are pervasive.
Here the dunes are apparently created by winds locally coming from the West and North-West, and generally blowing toward the East. The dunes are interspersed with radar-bright features that are inferred to rise above the surrounding terrain.
In the lower part of the image there are no dunes at all, and the texture is more typical of featureless plains observed in many other areas of Titan that lack dunes.
In this Transition Zone, the sand-sized particles that make up the dunes might not be so plentiful. In this case, insufficient sand to replenish the dunes makes them gradually disappear.
To compare the nature of these dunes to those seen at the Northern Boundary of the dune fields observed in radar images obtained during the T3 flyby on Feb. 15, 2005 see PIA07009.
The image is centered near 19,2° South Lat. and 257,4° West Long.
It covers an area of about 220 Km (approx. 137 miles) by about 170 Km (approx. 106 miles). North is approximately toward the top of the image, the radar illumination is from the right, and the Solar Incidence Angle is about 25° (meaning that the Sun was 65° above the Local Horizon).
The vertical stripe across the image at its center is an artifact in this preliminary version.MareKromium
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Titan-Map-Wind_Patterns-PIA11801.jpgMapping Titan's Global Wind Patterns56 visiteScientists have used data from the Cassini Radar Mapper to map the Global Wind Pattern on Saturn's moon Titan using data collected over a four-year period, as depicted in this image.
The arrows indicate the direction in which sand is inferred to be transported along dunes observed in Titan radar data.
Underlying the arrows is a base map (PIA08399) from Cassini's Imaging Science Subsystem.
Many of the equatorial dark areas without arrows might have dunes but have not yet been imaged with radar. The dune orientations represent only the net effect of winds. It could be that sand transport only occurs on rare occasions, and winds from different directions can combine to yield the observed dune orientations.MareKromium
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Titan-N00051470.gifApproaching the Clouds of Titan (GIF-Movie - credits: Dr M. Faccin)56 visitenessun commentoMareKromium
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Titan-N00081033.jpgFrom "RAW" to Natural Colors: Titan (credits: Dr M. Faccin)56 visitenessun commentoMareKromium
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Titan-Surface-34-PIA06440.jpgOn the Surface... (Natural Colors; credits: Lunar Explorer Italia)56 visitenessun commentoMareKromium
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Titan-PIA11508.jpgTitan in Eclipse56 visiteCaption NASA:"The Cassini spacecraft captured this image of a dimly lit Titan as Saturn's largest moon was eclipsed by the Planet.
This view looks up toward the South Pole of Titan which lies on the Terminator about a quarter of the way inward from the right of the visible disk. Lit terrain seen here is on the Saturn-facing side of Titan. In Saturn's shadow, the Southern Hemisphere of Titan is lit by two sources: sunlight scattered through the Planet's Rings and refracted sunlight passing through the edge of Saturn's Atmosphere.
Stars in this image are smeared by the long camera exposure time of 560" needed to capture the faint light on Titan. The image was taken in Visible Light with the Cassini Spacecraft wide-angle camera on May 7, 2009. The view was acquired at a distance of approx. 667.000 Km (about 414.000 miles) from Titan and at a Phase Angle of 58°.
Image scale is roughly 40 Km (about 25 miles) per pixel".MareKromium
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Titan-N00149992-N00150001.jpgTitan, in Time... (Natural Colors; credits: Elisabetta Bonora - Lunexit Team)56 visitenessun commentoMareKromium
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Titan-Mountains-PIA12496.jpgNew Wrinkles on Titan (Colorization made on Radar Image - credits: Dr Paolo C. Fienga - Lunexit Team)56 visiteIn this Synthetic Aperture Radar (SAR) image obtained by NASA's Cassini Spacecraft, two generally similar features, upper center and lower right, appear to be low Mountains with Grooves running roughly in the up-down direction.
A set of straight lines are also visible at lower left.
But what made the Grooves?
Grooves can result from forces that originate from within a planet - including forces that pull the Crust of a planet apart and cracks produced by melt intruding into the Crust.
They can also come from external forces like wind or rainfall, which produces river channels that can cut down through layers of rock.
All of these produce grooves on Earth's Surface, and may also be at work on Titan.
Another intriguing thing about this image is that in this image the "light" (actually the radar illumination) comes from the top. With this kind of illumination, the upper side of these mountains should be bright because they face the illumination, but the left side of the upper-center feature and the right side of the lower feature are bright. The brightness indicates that there is a different material in these areas, and the Grooves exist in both dark and light materials.
The Titan Radar Mapper acquired this image at 41° North Latitude and 213° West Longitude on December 28, 2009.
The image measures approx. 250 Km (about 160 miles) high and approx. 285 Km (about 180 miles) wide, with resolution of roughly 350 meters (1100 feet) per pixel. North is on the left, and the image is illuminated from the top.
The S.I.A. varies from 11 to 25°.
Two dark horizontal lines that run across the middle of the image show the joints between individual radar beams and are not features on the Titan Surface.MareKromium
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Titan-PIA12843.jpgWhat's inside Titan?56 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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