| Piú viste - Titan: The "Foggy" Moon |
Titan-PIA06138_modest.jpgTitan: the anomalous "circular" surface features are "camera artifacts"54 visiteCaption NASA originale from Planetary Photojournal:"The large, bottom image shows a complex interplay between dark and bright material on Titan's surface. This image was taken at a range of about 340.000 Km and the entire view is approximately 2.000 Km across. The surface appears to have been shaped by multiple geologic processes. Although a few "circular features" can be seen, there are no features that can be definitively identified as impact craters. The 3 smaller images show details of some of the features seen within the larger scene. The image on the upper right shows a scene approximately 500 Km across in which bright and dark bands of material span Et to Wt. The upper middle and upper right images show bright material surrounded by dark material in scenes approximately 300 Km across. The dark circular feature that appears at the top of each of the upper images is an artifact that was not removed by the preliminary image processing. There are no shadows or topographic shading visible in these images".
|
|
Titan-PIA06980_modest.jpgTitan: a "Secret Dream" for the Oil Companies"?54 visiteTitano, a quanto è emerso sino ad ora, potrebbe davvero essere (o diventare) un "sogno" per le grandi Multinazionali Petrolifere del nostro Pianeta. Perchè? Osservate il grafico e leggete le note originali NASA...:"This graph shows data acquired by Cassini as it flew by Titan at an altitude of 1.200 Km on Oct. 26, 2004 - its closest approach yet to the Hazy Moon. The data is from Cassini's ion and neutral mass spectrometer, which detects charged and neutral particles in the atmosphere. The graph reveals a diversity of hydrocarbons in the high atmosphere above Titan, including benzene and diacetylene". Ora, una delle tante (e neanche tanto nascoste...) verità che giacciono alle spalle dell'esplorazione spaziale, è nella ricerca di fonti energetiche significative e sfruttabili. Titano sembra proprio essere un Pianeta costituito - prevalentemente - da idrocarburi. La domanda è: premesso che un interesse commerciale può esistere, come fare a sfruttare le risorse di Titano in maniera economicamente vantaggiosa?
|
|
Titan-PIA06982_modest.jpgTitan from 1.200 Km54 visiteCaption NASA originale:"These images show the surface of Titan at two different infrared wavelengths. They were captured by the visual and infrared mapping spectrometer onboard Cassini as the spacecraft flew by at an altitude of 1200 Km - Cassini's closest approach yet to the Hazy Moon. The image on the left, taken at a wavelength of 2 microns, is the most detailed picture to date of the Titan's surface. It reveals complex landforms with sharp boundaries, which scientists are eager to further study. The image on the right was taken at a wavelength of 1 micron and shows approximately what a digital camera might see". Ad essere sinceri, da queste primissime immagini ravvicinate non riusciamo a distinguere praticamente nulla. Dobbiamo attendere che al Controllo Missione elaborino meglio le immagini giunte sino ad ora prima di lanciarci in nuove speculazioni relative alla configurazione effettiva della superficie di Titano. Abbiamo atteso anni, possiamo aspettare ancora qualche settimana...
|
|
Titan-PIA06987_modest.jpgTwo Views of Titan's Haze54 visiteCaption NASA originale:"These images show 2 views of Titan's planet-wide stratospheric haze just before (left) and after (right) Cassini's first close encounter with the Shrouded Moon. The image on the left was taken on Oct. 25, 2004, through an ultraviolet filter, which is sensitive to scattering of sunlight by small haze particles. It shows the high-altitude haze at the North Pole (top) illuminated above a surface blanketed in darkness during this winter season. Numerous striations are visible in the haze, indicating either waves passing through the layer or the presence of multiple layers.
The image on the right was taken on Oct. 26, 2004 and shows Titan's night-side backlit by the Sun, after Cassini's closest approach to the moon. The haze layer ringing the planet is illuminated because the small particles scatter significant sunlight in the forward direction. Variations in haze concentration and thickness around the globe are also evident and seem to be symmetric around the north pole (upper left)".
|
|
Titan-PIA06151_modest.jpgTitan from about 810.000 Km54 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?
|
|
Titan-PIA07876.jpgA bright Red Spot on Titan (1)54 visiteThe recently discovered infrared-bright spot on Titan is the type of enigmatic feature that is best investigated by putting together as many different types of complementary information as possible. This montage shows the spot in infrared wavelengths from the visual and infrared mapping spectrometer on the left, from the imaging science subsystem in the center and a combination of both data sets on the right. When put together, the 2 different views show more than either does separately. The visual and infrared spectrometer team noted the bright region in the image on the left after March 31, 2004, Cassini's-Titan encounter. The strange, bright feature to the southeast of Xanadu was flagged as unusual and informally dubbed "The Smile" by imaging team members in December 2004. It seems clear that both instruments are detecting the same basic feature on Titan's surface. This bright patch may be due to an impact event, landslide, cryovolcanism, or atmospheric processes. Its distinct color and brightness suggest that it may have formed relatively recently".
|
|
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.
|
|
Titan-PIA07565.jpgTitan's Terminator...from about 1,3 MKM54 visiteTitan's equatorial latitudes are distinctly different in character from its South Polar Region, as this image shows. The dark terrain, presumably lowland, seen here does not extend much farther south than about 30° South. The successful Huygens probe landed in such a Region. The Huygens probe is rotating into the light here, seeing the dawn of a new day. The bright region toward the right side of Titan's disk is Xanadu. This area is thought to consist of upland terrain that is relatively uncontaminated by the dark material that fills the lowland regions.
Near the South Pole, and just eastward of the terminator, is the dark feature identified by imaging scientists as the best candidate (so far) for a past or present hydrocarbon lake on Titan (see PIA06241). Farther east of the lake-like feature, bright clouds arc around the Pole. These clouds occupy a latitude range that is consistent with previously-seen convective cloud activity on Titan. The phase angle is 60° while the image scale is 7 Km per pixel.
|
|
Titan-PIA07730.jpgTitan, from about 159.000 Km54 visiteThis processed image from Cassini's Aug. 22, 2005, flyby of Titan reveals mid-latitudes on the Moon's Saturn-facing side.
Provisional names recently have been applied to a number of features on Titan. Features within the Region seen here - long known informally as the "H" - now have names like Tsegihi, Aztlan and Quivira.
The bright 215-Km-wide feature provisionally named "Bazaruto Facula" is clearly visible right of center, with its dark, unnamed 80-Km-wide crater at its center.
This view was acquired with the wide-angle camera at a distance of approx. 159.000 Km from Titan using a spectral filter centered on infrared wavelengths at 939 nnmts. The image scale is 9 Km per pixel.
Previous observations indicate that, due to Titan's thick and very hazy atmosphere, the sizes of surface features that can be resolved are a few times larger than the actual pixel scale.
|
|
Titan-W00012695.jpgTitans... (2)54 visiteOriginal caption:"W00012695.jpg was taken on December 26, 2005 and received on Earth December 27, 2005. The camera was pointing toward TITAN that, at the time, was approximately 25.404 Km away.
Te image was taken using the CL1 and RED filters".
|
|
Titan-PIA07700.jpgThe Atmosphere of Titan54 visiteThe view of Titan (almost natural colors) has been greatly contrast-enhanced to better show some intriguing structure in the North of the Planet; such intriguing "clouds-structure" is also clearly visible in a violet light view (PIA07701) taken at about the same time.
The color view was created by combining images taken using red, green and blue spectral filters. The images were taken with the Cassini spacecraft wide-angle camera on Dec. 26, 2005, at a distance of approx. 193.000 Km (about 120.000 miles) from Titan and at a phase angle of 29°. The image scale is about 11 Km (roughly 7 miles) per pixel.
|
|
Titan-PIA07707.jpgSmiling Titan...54 visiteThis infrared view shows features on the Leading Hemisphere of Titan, including the bright, crescent-shaped Hotei Arcus (right of center), which is also informally called "the Smile" by researchers.
The view is centered on the bright Region called Xanadu. Above center is the large crater Minerva, which is surrounded by darker material.
This image was taken with the Cassini spacecraft narrow-angle camera on Jan. 13, 2006 using a spectral filter sensitive to wavelengths of infrared light centered at 938 nnmts. The image was acquired at a distance of approx. 1,3 MKM (800.000 miles) from Titan and at a phase angle of 41°. Image scale is about 7 Km (approx. 5 miles) per pixel.
|
|
| 426 immagini su 36 pagina(e) |
 |
|
|
|
|
|
|
|
34 | |
|
