| Piú votate - Titan: The "Foggy" Moon |
Titan-Cryovolcanism-02.jpgCryovolcanism on Titan? (3)55 visiteInsomma: è più "credibile" che la nostra Scienza sia ancora fortemente limitata ed il nostro Sapere ancora - purtroppo - molto lontano dal potersi definire capace di interpretare con assoluta accuratezza una buona parte dei fenomeni che accadono nel nostro (piccolo) Sistema Solare e quindi nell'Universo oppure dobbiamo arrenderci all'idea che ormai 'abbiamo capito tutto' (o 'quasi tutto'...) e che ogni fenomeno è spiegabile facendo ricorso ad una macchina fotografica, ad uno spettrometro ad infrarossi ed a qualche altro aggeggio elettronico dalla sigla impossibile a pronunciarsi?
Scienza non è solo calcolo ma è anche (e forse soprattutto...) riflessione, umiltà, senso comune, capacità di meravigliarsi, capacità di dire - talvolta - "non sappiamo, non abbiamo idea di che cosa stiamo guardando".
Pensateci sopra...
(7 voti)
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Titan-PIA07877.jpgA bright Red Spot on Titan (2)54 visiteThis dramatic color (but not true color) image was taken during the April 16, 2005, encounter with Titan. North is to the right. In the center it shows the dark lanes of the "H"-shaped feature discovered from Earth and first seen by Cassini last July shortly after it arrived in the Saturn system. At the southwestern edge of the "H" feature, near Titan's limb, is an area roughly 500 Km across. That area is 50% brighter when viewed using light with a wavelength of 5 microns, than the bright continent-sized area known as Xanadu. At wavelengths shorter than 5 microns, the spot is not unusually bright. The strange spectral character of this enigmatic feature has left the Team with 4 possibilities for its source: the spot could be a surface coloration, a mountain range, a cloud or a hot spot. The hot spot hypothesis will be tested during a Titan flyby on July 2, 2006, when the visual and infrared spectrometer will take nighttime images of this area. If it is hot, it will glow at night.
(7 voti)
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Titan-Craters-Unnamed_Crater-PIA07868_fig1.jpgTitan's most prominent Impact Crater58 visiteCaption NASA originale:"This 3-panel image shows one of Titan's most prominent impact craters in an infrared-wavelength image (left), radar image (center) and in the false-color image (right). The Cassini radar imaged this crater during Cassini's 3rd flyby of Titan, on Feb. 15, 2005. The Crater, located at 16° West, 11°North, is about 80 Km in diameter and is surrounded beyond that by a blanket of material thrown out of the crater during impact. In radar, brighter surfaces mean rougher terrains, or else terrains tilted toward the radar. The Crater has a dark floor and a small bright area in the center and it is surrounded by bright material, which has a very faint halo slightly darker than the surrounding dark material".
(7 voti)
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Titan-2-PIA06230.jpgTitan in three different wavelenghts: the natural Titan (2)57 visiteCaption NASA originale:"This natural color composite was taken during the Cassini spacecraft's April 16, 2005, flyby of Titan. It is a combination of images taken through three filters that are sensitive to red, green and violet light.
It shows approximately what Titan would look like to the human eye: a hazy orange globe surrounded by a tenuous, bluish haze. The orange color is due to the hydrocarbon particles which make up Titan's atmospheric haze. This obscuring haze was particularly frustrating for planetary scientists following the NASA Voyager 1 and 2 mission encounters in 1980-81. Fortunately, Cassini is able to pierce Titan's veil at infrared wavelengths (see also PIA06228). North on Titan is up and tilted 30° to the right".
(7 voti)
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Titan-Surface-31.pngFirst real color view of Titan55 visiteCaption ESA originale:"This image was returned yesterday, 14 January 2005, by ESA's Huygens probe during its successful descent to land on Titan. This is the coloured view, following processing to add reflection spectra data, gives a better indication of the actual colour of the surface. Initially thought to be rocks or ice blocks, they are more pebble-sized. The two rock-like objects just below the middle of the image are about 15 cm(left) and 4 cm (centre) across respectively, at a distance of about 85 cm from Huygens. The surface is darker than originally expected, consisting of a mixture of water and hydrocarbon ice. There is also evidence of erosion at the base of these objects, indicating possible fluvial activity".
(7 voti)
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Titan-Shoreline_and_Drainage_Channels-00.jpgShoreline and Drainage Channels' Network on Titan 55 visiteCaption ESA originale:"This is one of the first raw images returned by the ESA Huygens probe during its successful descent. It was taken from an altitude of 16,2 Km with a resolution of approximately 40 metres per pixel. It apparently shows short, stubby drainage channels leading to a shoreline".
Il profilo di un tratto costiero, dunque: montagne (o colline), una fitta rete di canali ed una porzione di "mare" alla vista. Mare.
Già, ma un mare fatto di cosa?...
(7 voti)
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Titan-W00003639.jpgClouds around Titan55 visiteImmagine di Titano ripresa da circa 29.000 Km. Oltre alle nuvole (sempre bianche e vaporose) non si riesce a distinguere alcun dettaglio della superficie di questa luna.
(7 voti)
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Titan-Undefined_Surface_Features-Radar_Image-PIA06992_modest.jpgTitan - Radar image and false color image55 visiteCaption NASA originale: "In the new color image, brighter areas may correspond to rougher terrains, slopes facing the radar, or different materials. The pink colors enhance smaller details on the surface, while the green color represents smoother areas. Winding linear features that cut across dark areas may be ridges or channels, although their nature is not yet understood. A large dark circular feature is seen at the western (top left) end of the image, but very few features on Titan resembling fresh impact craters are seen.
The area shown is in the northern hemisphere of Titan and is about 150 Km wide by 300 Km long.
The image is a part of a larger strip created from data taken on Oct. 26, 2004, when the Cassini spacecraft flew approximately 1.200 Km above Titan's surface".
(7 voti)
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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...
(7 voti)
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Titan from Voyager.jpgTitan from Voyager 2 (in HR)58 visiteTitan Data and Statistics
Discovered by = Christiaan Huygens
Date of discovery = 1655
Mass (kg) = 1.35e+23
Mass (Earth = 1) = 2.2590e-02
Equatorial radius = 2.575 Km
Equatorial radius (Earth = 1) = 4.0373e-01
Mean density (gm/cm^3) = 1,88
Mean distance from Saturn = 1.221.850 Km
Rotational period (days) = 15,94542
Orbital period (days) = 15,94542
Mean orbital velocity (km/sec) = 5,58
Orbital inclination = 0,33°
Escape velocity (km/sec) = 2,65
Visual geometric albedo = 0,21
Magnitude (Vo) = 8,28
Mean surface temperature = -178°C
Atmospheric pressure (bars) = 1,5
(7 voti)
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Titan-Regions-Adiri-PIA12621-PCF-LXTT-IPF.jpgThrough the Fog: Adiri (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga/Lunar Explorer Italia/Italian Planetary Foundation)112 visiteThe NASA - Cassini Spacecraft peers through the Dark and Hazy Atmosphere of Titan, this time looking at a Region called Adiri, and located to the West of the Landing Site of the ESA - Huygens Probe, on the Anti-Saturn Side of the moon. This view is centered on Terrain at 22° South Latitude and 209° West Longitude. North on Titan is up and rotated 36° to the right. The dark Circular Feature visible slightly on to the right of the image center, at about 2 o'clock (and that looks like a well preserved Impact Crater seen from atop), could actually be an Image-Artifact.
The image was taken with the NASA - Cassini Spacecraft Narrow-Angle Camera on December 12, 2009, using a spectral filter sensitive to Wavelengths of Near-InfraRed Light centered at 938 nanometers. The view was obtained at a distance of approximately 130.000 Km (such as about 81.000 miles) from Titan. Image scale is 766 meters (such as 2513 feet) per pixel.
This picture (which is an Original NASA - Cassini Spacecraft b/w frame published on the NASA - Planetary Photojournal and identified by the n. PIA 12621) 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 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 Albedo Feature seen in this frame would appear, to an average human eye, way lower than it has been shown (better yet: interpreted) here.MareKromium
(6 voti)
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Titan-MF-LXTT.gifColor Variations on Titan (a GIF-Movie by Dr Marco Faccin - Lunexit Team)64 visitenessun commentoMareKromium
(6 voti)
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