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Titan-Map-PIA02147.jpgGlobal Titan Map (Visual + IMS)55 visiteThis global infrared map of Titan was composed with data from Cassini's visual and infrared mapping spectrometer taken during the last two Titan flybys, on Dec. 26, 2005, and Jan. 15, 2006.
There are several important features to note in this Map:
1) the globe of Titan exhibits 2 major types of terrain: one is very bright, and a darker one seems to be concentrated near the Equator;
2) Titan has two very bright Regions: the large one known as Tui Reggio, located at approx. 25° South Lat. and 130° West Long., and the other as Hotei Arcus, at 20° South Lat. and 80° West Long. These regions are thought to be surface deposits, probably of volcanic origin, and may be water and/or carbon dioxide frozen from the volcanic vapor; the western margins of Tui Reggio have a complex flow-like structure consistent with eruptive phenomena;
3) the reddish feature at the South Pole is Titan's South Polar cloud system, which was very bright during the December flyby;
4) The Sinlap Crater is clearly visible at approx. 13° North Lat. and 16° West Long. The poorly resolved Regions between Longitudes of 30° and 150° East will be filled in during subsequent flybys.
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Titan-Map-PIA11146.jpgUpdated Map of Titan56 visiteCaption NASA:"These updated maps of Saturn's moon Titan, consisting of data from the Cassini imaging science subsystem, include Cassini's August 2008 imaging of the moon's Northern Hemisphere.
Evidence from Cassini's imaging science subsystem, radar, and Visual and InfraRed Mapping Spectrometer instruments strongly suggests that dark areas near the Poles are lakes of liquid hydrocarbons (an analysis affirmed by images capturing those changes in the lakes thought to be brought on by rainfall).
Colored lines in the polar portions of these maps illustrate the boundaries between surface regions having different albedos — or differences in surface brightness — which Cassini scientists have interpreted as potential shorelines. Blue outlines indicate features that changed between observations made one year apart (see also PIA11147).
The top map is a simple cylindrical projection. Atmospheric effects complicate incorporation of data from high Northern Latitudes, which are shown separately in a polar view. The map at bottom left is a North Polar projection showing latitudes 55° to 90°. The bottom right map is a South Polar projection showing latitudes - 55° to - 90°.
The maps are compiled from images dating from April 2004 through August 2008, and their resolutions vary from a few meters to a few tens of kilometers per pixel. Brightness variations are due to differences in surface albedo rather than topographic shading".MareKromium
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Titan-Map-PIA11149.jpgTitan's Global Digital Map (credits: NASA/JPL/Space Science Institute)55 visiteThis Global Digital Map of Saturn's moon Titan was created using images taken by the Cassini Spacecraft's Imaging Science Subsystem.
The images were taken using a filter centered at 938 nanometers, allowing researchers to examine variations in albedo (or inherent brightness) across the Surface of Titan. Because of the scattering of light by Titan's dense Atmosphere, no topographic shading is visible in these images.
The map is an equidistant projection and has a scale of 4 Km (about 2,5 miles) per pixel. Actual resolution varies greatly across the map, with the best coverage (close to the map scale) near the center and edges of the map and the worst coverage on the Leading Hemisphere (centered around 120° West Long.).
Imaging coverage in the Northern Polar Region continues to improve as Titan approaches northern vernal equinox in August 2009 and the North Pole comes out of shadow. Large dark areas, strongly suspected to be liquid-hydrocarbon-filled lakes, have been documented at high at high latitudes (see PIA11146).
The mean radius of Titan used for projection of this map is 2,575 kilometers (1,600 miles). Until a control network is created for Titan, the satellite is assumed to be spherical.
MareKromium
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Titan-Map-Wind_Patterns-PIA11801.jpgMapping Titan's Global Wind Patterns54 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-Mountains-PIA10654.jpgTitanian Tectonics - radio-image; credits: NASA54 visiteOvviamente la "linea" è un ovvio image-artifact, come la NASA stessa ci riferisce e spiega NELLE ULTIME DUE RIGHE DEI COMMENTI UFFICIALI, ma noi abbiamo lasciato la sovraimpressione "evocativa di Mistero" sul frame al SOLO scopo di farVi capire - caso mai ce ne fosse stato ancora bisogno - QUANTO SIA FACILE CREARE BUFALE!
Soprattutto allorchè NON si presta la dovuta attenzione alle note "ufficiali" di commento ed allorchè non si è molto familiari con la Fotografia Spaziale in generale e con le Radio-Immagini in particolare.
Caption NASA:"A set of three parallel ridges was seen by the Cassini Spacecraft's Radar Instrument during the latest Titan flyby on May 12, 2008. This combination is unlikely to be a coincidence -- the best explanation for these features is that they are tilted or separated blocks of broken or faulted crust, now exposed as high ridges. Their regular spacing is typical of regions that have been compressed or extended over large areas; as an example, the western United States Basin and Range Province was formed by extension. Such interactions are called "Tectonics", although they do not happen in the same way as plate tectonics, which is a process unique to Earth.
The ridges, which appear on the left side of the image, are rugged features and are elevated above surrounding terrain. The brightness patterns mean that the materials are fractured or blocky at the radar wavelength (2,17 cm, or about 1" - one inch). Along the south sides of the ridges are prominent cliffs, or scarps, present as thin, radar-dark lines trending West-to-East, and interpreted as faults.
These features are dark due to shadowing from the radar illumination, and have heights up to a few hundred meters (several hundred feet), based on preliminary estimates of slopes.
The area shown here is located in the mountainous region called Xanadu.
The ridges are similar in many ways to mountain chains seen at similar latitude but about 90° to the West, just West of Shangri-La (observed during a flyby in October 2005, and showin a Sea of Sand-like Dunes).
Both Regions have mountain chains or ridges that are oriented West-to-East and are spaced about 50 Km (or about 30 miles) apart. This indicates tectonic forces have acted in a North to South direction at Titan's Equatorial Region and have resulted in regular effects in Titan's crust, evidence that will help scientists better understand Titan's crust and interior.
Other linear features, probably related to the formation of the ridges, and circular features, perhaps eroded impact craters now filled with radar-dark (smooth) material, are also seen in the image. The largest circular feature, at bottom center, is about 20 Km in diameter.
The image is centered at 2° South Lat. and 127° West Long. and was obtained on May 12, 2008, with a resolution of about 300 meters (980 feet). The open arrow indicates the direction of radar illumination.
The dashed white line in the upper portion is an artifact of the SAR processing and will be removed in later versions".MareKromium
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Titan-Mountains-PIA12496.jpgNew Wrinkles on Titan (Colorization made on Radar Image - credits: Dr Paolo C. Fienga - Lunexit Team)55 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-N00023130.jpgTitan54 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-N00023203.jpgTitan, from about 711.000 Km54 visiteI dettagli della superficie di Titano si evidenziano sempre di più, ma rimangono enigmatici. Qualcosa, ne sono tutti certi, sta accadendo nella densa atmosfera di Titano e, forse, le sue nuvole sono fucine attive di fenomeni atmosferici anche familiari (lampi, per esempio). Ma l'atmosfera di questa Luna non è l'unico motivo di interesse per Scienziati ed Appassionati! Titano sembra possedere degli oceani, ma nessuno sa dire che cosa ci sia dentro questi oceani (si pensa del metano, ma non si è ancora assolutamente certi). ). Inoltre Titano lascia intravedere anche dei particolari che dovrebbero riferirsi alla sua superficie solida, come quel cerchio scuro che potete vedere ad un terzo dell'altezza dell'immagine, verso la Vostra Dx. Cos'è? Un cratere? O forse una turbolenza simile a quelle che vediamo caratterizzare gli strati alti dell'atmosfera di Saturno? Dobbiamo ancora aspettare per avere risposte, ma noi siamo certi che qualcosa scoprireremo e sarà una sorpresa...
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Titan-N00051470.gifApproaching the Clouds of Titan (GIF-Movie - credits: Dr M. Faccin)55 visitenessun commentoMareKromium
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Titan-N00051529-1.jpgThrough the Titanian Clouds... (credits: Dr M. Faccin)55 visitenessun commentoMareKromium
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Titan-N00051529-2.jpgThrough the Titanian Clouds... (credits: Dr M. Faccin)55 visitenessun commentoMareKromium
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Titan-N00055564.jpgWhat's happening on Titan? (1)62 visiteCiò che Vi proponiamo in questa (lunga) sequenza di Titano potrebbe essere il frutto di una mera "misinterpretation" delle immagini (come ci direbbero i Signori del CICAP e gli Amici della NASA) oppure, come a noi piace credere, potrebbe trattarsi di un interessante fenomeno che prende le mosse e si sviluppa (o così pare) negli strati più alti dell'atmosfera di Titano.
Si tratta, in fondo, solo di un minuscolo "punto" ambiguo (9 pixels effettivi di diametro) che, nel tempo, sembra svilupparsi e che poi, improvviso come era arrivato, scompare.
Guardate ed esaminate anche Voi...
Nota: va detto, per correttezza, che la maggior parte dei frames che Vi proporremo è - purtroppo - piena di photoartifacts, anche se il "punto" che abbiamo cerchiato, a differenza degli altri difetti, si mantiene in una posizione che noi definiamo "coerente", nel tempo.
Caption NASA:"N00055564.jpg was taken on March 20, 2006 and received on Earth March 20, 2006. The camera was pointing toward Titan that, at the time, was about 972.114 Km away. The image was taken using the P120 and UV3 filters".
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