| Piú votate - Titan: The "Foggy" Moon |
Titan-N00091161.jpgTitan55 visiteCaption NASA:"N00091161.jpg was taken on September 02, 2007 and received on Earth September 03, 2007. The camera was pointing toward TITAN that, at the time, was approximately 1.313.086 Km away, and the image was taken using the CL1 and UV3 filters. This image has not been validated or calibrated".MareKromium
(5 voti)
|
|
Titan-N00084809.jpgInterpreting Titan (3)55 visitenessun commentoMareKromium
(5 voti)
|
|
Titan-N00084842.jpgInterpreting Titan (4)55 visitenessun commentoMareKromium
(5 voti)
|
|
Titan-N00084850.jpgInterpreting Titan (5)55 visitenessun commentoMareKromium
(5 voti)
|
|
Titan-W00028749.jpgOn the "Dark Side" of Titan...55 visitenessun commentoMareKromium
(5 voti)
|
|
Titan-Huygens_Landing_Site-00-LS27_PSS_LSoderblom_DISR_Topo20070323.jpgHuygens Probe Landing Site (perspective)56 visiteThis West-looking perspective of the Huygens Landing Site shows the Huygens descent trajectory in blue (the blue vertical lines indicate the ground track location). The base map (16 metres per pixel) is a mosaic obtained by the Descent Imager and Spectral Radiometer (DISR) on board Huygens.MareKromium
(5 voti)
|
|
Titan-Huygens_Landing_Site-05-LS27_PSS_LSoderblom_DISR_Topo20070323.jpgTectonic and fluid-flow patterns on Titan (HR)56 visiteThis image of Titan’s surface, obtained by Huygens’ DISR imager, shows patterns of tectonic and fluid-flow activity.
The tectonic patterns are indicated by blue lines; the drainage divide is indicated by the red line; flow directions are indicated by the green arrows.
The Huygens Landing Site is marked by a white cross.
MareKromium
(5 voti)
|
|
Titan-Surface-00-LS28_PSS_LASoderblom_VIMSRADAR20070323.jpgHuygens Probe Landing Site54 visiteThis image composite shows three different views of the Huygens landing site. The top image was obtained by Cassini’s VIMS instrument in the infrared. The middle one is a mosaic of all the images obtained by the DISR visible camera on board Huygens, and shows surface features. The bottom image was obtained by Cassini’s SAR radar. MareKromium
(5 voti)
|
|
Titan-Huygens_Landing_Site-04-IMG002629-br500.jpgDrainage, flow and erosion on the Huygens landing site56 visiteClose - by are stubby canyons with only a few branches. They have probably been formed by ‘spring sapping’, whereby methane flows through the subsurface before emerging as a spring near the base of a hill. The spring erodes the hillside, causing it to collapse and form a cliff face.
The third area is the flat dark plain. This is mostly water ice mixed with tholin grit. “Titan’s river channels, canyons, and flood plains rival the variety seen on Earth,” says Soderblom. The dark plains show markings that suggest the region occasionally experiences flash flooding, but not from the highland drainage channels. Instead large quantities of liquid methane appear to flow from east to west.
Planetary scientists can now begin to piece together the sequence of events that led to the formation of this exotic landscape. “Huygens and Cassini have taken giant steps forward in our understanding of Titan,” says Soderblom.
MareKromium
(5 voti)
|
|
Titan-PIA08945.jpgA new "Ortographic View" of Titan67 visiteBright and dark terrains on Titan's Trailing Hemisphere are revealed by Cassini's Imaging Science Subsystem in this mosaic of images taken during the T28 flyby in April 2007. The Region shown in this image, centered on the northern part of Titan's Trailing Hemisphere (near 31,2° North and 220,7° West), had only been seen at very low resolution until February 2007, when Cassini flew over this area for the first time. This mosaic consists of images taken during one of a series of flybys in early 2007 designed to study this long unavailable part of Titan.
Several intriguing surface features can be seen in this mosaic that warrant further study. Along the top of the mosaic is a series of dark lineaments, or linear features, that stand out against the blandness of the Northern, Mid-Latitude Terrain.
These features were also observed by the RADAR instrument in December 2006 and represent an area of potential future co-analysis for the RADAR and camera teams. Another such region is the large bright area known as Adiri at bottom center, also imaged by RADAR in October 2005.
The mosaic shows a number of dark areas within Adiri Regio that line up with small dune fields observed by RADAR. A portion of the dark terrain surrounding Adiri was also observed in 2005 by RADAR, and likewise was found to consist of large stretches of longitudinal dune fields - further supporting the correlation between equatorial dark regions and dune "seas".
To the East of Adiri is a dark spot surrounded by a ring of bright material, which may be associated with an impact crater similar to Sinlap, discovered earlier in the Cassini mission (see PIA6222).
This mosaic consists of 29 separate frames using a total of 116 images.
Each frame consists of three images, taken using a filter sensitive to near-infrared light centered at 938 nanometers, allowing for observations of Titan's surface and lower atmosphere, added together. An image taken using a filter sensitive to visible light centered at 619 nanometers was then subtracted from the product, effectively removing the lower atmosphere contribution to the brightness values in the image, increasing image contrast and improving the visibility of surface features.
This process is also intended to reduce noise, but some camera artifacts still remain, such as a dark ring caused by dust in the camera system near the bottom right of each frame.
The images used for this mosaic were taken on April 11, 2007 from distances ranging from approx. 106.000 to 180.000 Km (such as from about 66.000 to 112.000 miles).
This mosaic is in an orthographic view of Titan (an orthographic view is most like the view seen by a distant observer looking through a telescope).
MareKromium
(5 voti)
|
|
Titan-PIA08943.jpgAn "Orthographic View" of Titan54 visiteCaption NASA:"Cassini acquired this view of Titan on April 13, 2007, following a flyby of the Mercury-sized moon. Titan's equatorial Dark Regions are visible in this view, along with faint, dark lineaments (linear features) in the otherwise bland-looking terrain of the North. Near the Terminator are the dark, lake-like features identified in Cassini flybys early in 2007.
To the east of the lake-like features is a bright patch of clouds that likely consist of a mixture of Methane and Ethane.
This view of Titan is an orthographic reprojection centered on 27,4° North Latitude. An orthographic view is most like the view seen by a distant observer looking through a telescope.
The view was obtained using a filter sensitive to near-infrared light centered at 939 nanometers, allowing for observations of Titan's Surface and Lower Atmosphere, added together. An image taken using a filter sensitive to visible light centered at 619 nanometers was then subtracted from the product, effectively removing the lower atmosphere contribution to the brightness values in the image, increasing image contrast and improving the visibility of surface features.
The Cassini spacecraft acquired this view with its narrow-angle camera at a distance of approx. 1,2 MKM (about 800.000 miles) from Titan. Image scale is roughly 7 Km (such as about 5 miles) per pixel".
MareKromium
(5 voti)
|
|
Titan-Craters-Unnamed_Crater-PIA09175.jpgFresh Crater on Titan?58 visiteCaption NASA:"This radar image of Titan shows a semi-circular feature that may be part of an impact crater. Very few impact craters have been seen on Titan so far, implying that the surface is young. Each new crater identified on Titan helps scientists to constrain the age of the surface.
Taken by Cassini's radar mapper on Jan. 13, 2007, during a flyby of Titan, the image swath revealed what appeared to be the northernmost half of an impact crater. This crater is roughly 180 Km (about 110 miles) wide. Only three impact craters have been identified on Titan and several others, like this one, are likely to also have been caused by impact. The bright material is interpreted to be part of the crater's ejecta blanket, and is likely topographically higher than the surrounding plains. The inner part of the crater is dark, and may represent smooth deposits that have covered the inside of the crater.
This image was taken in synthetic aperture mode and has a resolution of approx. 350 mt (1150 feet). North is toward the top left corner of the image, which is approx. 240 Km (about 150 miles) wide by 140 Km (90 miles) high. The image is centered at about 26,5° North and 9° West".
(5 voti)
|
|
| 426 immagini su 36 pagina(e) |
 |
|
|
|
|
12 | |
|
|
|
|
