| |
| Piú votate - Titan: The "Foggy" Moon |
Titan-Huygens_Landing_Site-12-PIA07870-br500.jpgHuygens Landing Site56 visiteCaption NASA originale:"This stereographic projection of Descent Imager/Spectral Radiometer images from the European Space Agency's Huygens probe combines 60 images in 31 triplets, projected from a height of 3.000 mt (approx. 9.843 feet) above the black 'lakebed' surface. The bright area to the North (top of the image) and West is higher than the rest of the terrain and covered in dark lines that appear to be drainage channels.
The images were then stitched together using one of several projection algorithms (in this case 'stereographic') to produce a full mosaic. The images used to construct this mosaic were taken on Jan. 14, 2005. The Descent Imager/Spectral Radiometer is 1 of 2 NASA-funded instruments on the probe".
(3 voti)
|
|
Titan-Craters-Unnamed_Crater-PIA07368.jpgImpact Crater on Titan (radio-image)60 visiteCaption NASA originale:"This image shows a crater, approx. 60 Km in diameter, on the very eastern end of the radar image strip taken by the Cassini orbiter on its third close flyby of Titan on Feb. 15, 2005.
The appearance of the crater and the extremely bright (hence rough) blanket of material surrounding it is indicative of an origin by impact, in which a hypervelocity comet or asteroid, in this case, roughly 5-10 Km, in size, slammed into the surface of Titan. The bright surrounding blanket is debris, or ejecta, thrown out of the crater. The asymmetric appearance of this ejecta blanket could be an effect of "atmospheric winds" associated with the impact itself. Although clearly formed by impact, the feature lacks a central peak, suggesting that it has been eroded or otherwise modified after formation. Rainfall, wind erosion and softening of the solid material in which the crater formed are all possible processes that might have altered this impact feature".
(3 voti)
|
|
Titan-Channels-Drainage_Channels-PIA07236-01.jpgWater Ice and Methane Springs on Titan57 visiteCaption NASA originale:"A single Huygens DISR image that shows two new features on the surface of Titan. A bright linear feature suggests an area where water ice may have been extruded onto the surface. Also visible are short, stubby dark channels that may have been formed by 'springs' of liquid methane rather than methane rain".
Come mai, qualcuno si è chiesto, gli idrocarburi di Titano non sono completamente ghiacciati? Come mai - almeno a quanto ci è dato vedere - i "fiumi" e le "sorgenti" di idrocarburi di Titano, rispettivamente, scorrono e zampillano? Che cosa permette alla superficie di Titano di essere sufficientemente calda da consentire a questo incredibile mondo di essere - da un certo punto di vista - "vivo e vitale"?
(3 voti)
|
|
Titan-Close Up 8 (from 32.000 Km) W00002379.jpgTitan's fly-by "A" - Close-up 8 (from 32.000 Km)55 visitenessun commento
(3 voti)
|
|
Titan-PIA21890.jpgTitan118 visiteCaption NASA Originale:"As it glanced around the Saturn system one final time, NASA's Cassini Spacecraft captured this view of the planet's giant moon Titan. Interest in mysterious Titan was a major motivating factor to return to Saturn with Cassini-Huygens following the Voyager mission fly-bys of the early 1980s. Cassini and its Huygens probe, supplied by the ESA (European Space Agency), revealed the moon to be every bit as fascinating as scientists had hoped.
These views were obtained by Cassini's Narrow-Angle Camera on Sept. 13, 2017. They are among the last images Cassini sent back to Earth.
This natural color view, made from images taken using red, green and blue spectral filters, shows Titan much as Voyager saw it - a mostly featureless golden orb, swathed in a dense Atmospheric Haze. An enhanced-color view (such as this one) adds to this color a separate view taken using a spectral filter (centered at 938 nanometers) that can partially see through the haze.
The views were acquired at a distance of about 481.000 miles (such as approx. 774.094,464 Km) from Titan. The image scale is about 3 miles (roughly 4,828 Km) per pixel".MareKromium
(2 voti)
|
|
Titan-PIA21902.jpgThe uneven Atmosphere of Titan141 visiteLe diverse stratificazioni dell'Alta Atmosfera di Titano sono ben visibili in questa foto CASSINI dell'ormai lontano AD 2005.
In questo frame, ci appare del tutto evidente che la densità dell'Atmosfera di Titano NON é strettamente correlata all'altezza della stessa (ergo delle sue nuvole e nebbie) rispetto al Datum (Altitudine Zero); le turbolenze (e quindi anche la composizione chimica dell'Atmosfera) sembrano estendersi e rivolgersi, a volte, da strati più bassi verso quelli più alti, mentre, in altri casi, sembra avvienire esattamente l'opposto.
Questa conclusione é stata basata sull'esame di immagini sequenziali che coprissero la medesima Regione Titaniana per svariati minuti (o decine di minuti). In questo frame le innumerevoli "disomogeneità" sono del tutto palesi.
Non possiamo neppure escludere l'esistenza di (violentissime) correnti convettive le cui cause, tuttavia, non sono ancora chiare.
Caption NASA Originale:"In this view, individual Layers of Haze can be distinguished in the Upper Atmosphere of Titan, Saturn's largest moon. Titan's Atmosphere features a rich and complex chemistry originating from Methane and Nitrogen (---> Azoto) and evolving into complex molecules, eventually forming the "Smog! that surrounds the moon (even at extremely lower altitudes).
This Natural Color image was taken in Visible Light with the Cassini Spacecraft wide-angle camera on March 31, 2005, at a distance of approximately 20.556 miles (such as about 33.081,67 Km) from Titan. The view looks toward the North Polar Regions on the moon's Night-Side. Part of Titan's sunlit crescent is visible at right (Dx).
The Cassini Spacecraft ended its mission on Sept. 15, 2017".MareKromium
(2 voti)
|
|
Titan-PIA21624.jpgDouble Titan138 visiteCaption NASA:"These two views of Saturn's moon Titan exemplify how NASA's Cassini Spacecraft has revealed the Surface of this fascinating world.
Cassini carried several instruments to pierce the veil of hydrocarbon haze that enshrouds Titan. These include the Spacecraft's Radar and the Visual and InfraRed Mapping Spectrometer, or VIMS. The mission's imaging cameras also have several spectral filters sensitive to specific wavelengths of InfraRed Light that are able to make it through the Haze to the Surface and back into space. These "spectral windows" have enable the imaging cameras to map nearly the entire surface of Titan.
In addition to Titan's Surface, images from both the imaging cameras and VIMS have provided windows into the moon's ever-changing Atmosphere, chronicling the appearance and movement of Hazes and Clouds over the years. A large, bright and feathery band of Summer Clouds can be seen arcing across high Northern Latitudes in the view at right (Dx).
These views were obtained with the Cassini Spacecraft Narrow-Angle Camera on March 21, 2017. Images taken using red, green and blue spectral filters were combined to create the Natural-Color View on the left (Sx).
The false-color view at right (Dx) was made by substituting an InfraRed image (centered at 938 nanometers) for the red color channel.
The views were acquired at a distance of approx. 613.000 miles (such as a little more than 986.000 Km) from Titan and the Image Scale is roughly 4 miles (such as approx. 6,437 Km) per pixel".MareKromium
(2 voti)
|
|
Titan-Fensal_and_Aztlan-PIA07732-PCF-LXTT-IPF-0.jpgFensal and Aztlan (CTX Image-Mosaic - Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga/Lunar Explorer Italia/Italian Planetary Foundation)62 visiteDuring its September 7, 2005, Fly-By of the Saturnian moon Titan, the NASA - Cassini Spacecraft acquired a series of images of a Territory located on the moon's Saturn-facing Hemisphere that were afterwards assembled so to create this small mosaic: once known only as "The H" (because this whole Region looks something like the letter "H", when oriented on its side), the Surface Features visible here now possess provisional names that were assigned to them by the International Astronomical Union (or "IAU", for short).
The Northern Branch of "The H" is now called "Fensal," while the Southern Branch is known as "Aztlan."
Fensal is littered with small "Island-like Landforms" ranging in size from about 5 to 40 Km (such as from approx. 3,1 to a little less than 25 miles) across. These Landforms currently are thought to be Water-Ice Upland Areas (---> kind of small Hills), surrounded by shallower Terrain that is filled-in with dark Particulate Material probably precipitated from the Lower Atmosphere of Titan. In Western Fensal, a few larger Islands can also be seen, like Bazaruto Facula (visible to the right here and containing what seems to be an Impact Crater or, maybe, a Volcanic Edifice). When viewed in images of Shangri-La (another Titanian Region located on the opposite side of Titan as to Fensal and Aztlan), the Island-like Landforms of this size tend to occur in "clusters" (---> groups) with an apparent so-called "Preferred Orientation" (perhaps due to the action of the Dominant Winds blowing over those Territories). The small Islands found in Fensal, instead, appear much more scattered (and most of them appear roughly circular), although a few Islands do have (show) an East-West orientation to their long axis.
Aztlan, on the other hand, appears comparatively devoid of small Island-like Landforms, with only three large Islands located in its Western Reaches, plus only a few smaller Islands. The largest one of these Landforms is called "Sotra Facula" (visible just right of center in the bottom left portion of the mosaic), and measures approx. 240 by 120 Km (such as about 149 to 74,52 miles) across.
The mosaic is centered at 7° North Latitude and 21° West Longitude on Titan and the frames composing it were taken by the NASA - Cassini Spacecraft Narrow-Angle Camera using a filter sensitive to Wavelengths of Near-InfrarRed Light centered at 938 nanometers. They were acquired at distances ranging from approximately 200.600 to 191.800 Km (such as from about 124.572 to 119.108 miles) from Titan. The Mean Resolution in the images forming the mosaic is about 2 Km (such as 1,242 miles) per pixel.
This picture (which is an Original NASA - Cassini Spacecraft b/w image-mosaic published on the NASA - Planetary Photojournal and identified by the n. PIA 07732) has been additionally processed, magnified, contrast enhanced and then colorized, according to an educated guess 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 Clouds and Hazes (as well as the luminosity of the Surface of Titan itself), as seen in this mosaic, would appear, to an average human eye, way lower than it has been shown (or, better yet: interpreted) here.MareKromium
(2 voti)
|
|
Titan-PIA14663-PCF-LXTT-IPF.jpgFensal, Aztlan and Kraken Mare (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga/Lunar Explorer Italia/Italian Planetary Foundation)59 visiteAlthough it is almost completely hidden from human eyes, the NASA - Cassini Spacecraft can still spot a few dark Features on the Surface of Titan thanks to its special Near-InfraRed Filters. The Surface Features visible here, near the Equatorial Belt, have been dubbed "Fensal" and "Aztlan" by Planetary Scientists and they are believed to be vast (---> large and very long) Dunes made of Particles of Dust (mixed-up with, most likely, other Elements) that precipitated out of the Atmosphere of Titan (but some other possibilities about their origin and composition can also be well considered); on the other hand, near the North Pole of Titan, it is also well visible the largest body of liquids existing on this fascinating Saturnian moon, such as the Kraken Mare.
Furthermore, just barely visible right on top of the South Pole, the huge Vortex that was spotted quite some time ago and that keeps Planetary Scientists busy trying to understand the actual reasons that caused its sudden formation, as well as and the amount of time during which it will still remain active (obviously assuming that such a Vortex is just a seasonal and not a - now - permanent phenomenon).
This view looks toward the Saturn-facing Hemisphere of Titan; North is up and rotated 32° to the right (Dx) and the image was taken with the NASA - Cassini Spacecraft Narrow-Angle Camera on April 13, 2013 using a Spectral Filter sensitive to Wavelengths of Near-InfraRed Light centered at 938 nanometers. The view was acquired at a distance of approximately 1,2 Million Miles (such as about 1,93 Million KiloMeters) from Titan and at a Sun-Titan-Cassini Spacecraft, or Phase, Angle of 4°. The image scale is roughly 7 miles (such as about 11,26 Km) 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 14663) has been additionally processed, magnified and then colorized, according to an educated guess 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 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 Clouds and Hazes (as well as the luminosity of Titan itself) seen in this frame would appear, to an average human eye, way lower than it has been shown (or, better yet: interpreted) here.MareKromium
(2 voti)
|
|
Titan-Senkyo_Region-PIA14655-PCF-LXTT-IPF.jpgSenkyo Region (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga/Lunar Explorer Italia/Italian Planetary Foundation)87 visiteThe NASA - Cassini Spacecraft's "Electronic Eyes" peer through Titan's thick layers of Clouds to spy on the Region dubbed "Senkyo" by Planetary Scientists. Among the Dark Surface Features visible in this picture there is also a very vast Field of Dunes, possibly composed of solid Hydrocarbon Particles precipitated out of the Titanian Atmosphere; furthermore, the South Pole of Titan is, as you can see, still shrouded in the huge Vortex that formed only a few months ago (and whose origin is still debated). The lit Terrain seen here is located on the Saturn-facing Hemisphere of Titan; North is up and rotated 18° to the right.
This image was taken with the NASA - Cassini Spacecraft's Narrow-Angle Camera on January 5, 2013, by using a spectral filter sensitive to Wavelengths of Near-InfraRed Light centered at 938 Nanometers. The view was obtained at a distance of approximately 750.000 miles (such as a little more than 1,2 Million KiloMeters) from Titan and at a Sun-Titan-Cassini Spacecraft , or Phase, Angle of 79°. Image scale is roughly 4 miles (such as about 6,43 Km) 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 14655) has been additionally processed and then colorized, according to an educated guess 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 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 Clouds and Hazes (as well as the luminosity of Titan itself) seen in this frame would appear, to an average human eye, way lower than it has been shown (or, better yet: interpreted) here.MareKromium
(2 voti)
|
|
Titan-Lakes-South_Polar_Lake-01-PIA06241-PCF-LXTT-IPF-002.jpgOntario Lacus and the South Polar Regions of Titan: after the Fog (Absolute Natural Colors; credits for the additional process. and color. Dr Paolo C. Fienga/Lunar Explorer Italia/Italian Planetary Foundation)99 visiteThis view of Titan’s South Pole reveals the intriguing Dark Feature named Ontario Lacus and a host of smaller features dotting the whole South Polar Region. The true nature of this Surface Feature, seen here at left of center, is not yet known with absolute certainty. However, the Feature’s extremely dark coloration, the shore-like smoothness of its perimeter, and its presence in an area where frequent Convective Storm Clouds have been observed by the NASA - Cassini Spacecraft and Earth-based telescopes, made it the best candidate for an open body of liquid on Titan when this image was taken, in June 2005. This interpretation has, afterwards, been strengthened by the sighting of Surface Features having similar morphologies, but this time in Titan’s North Polar Regions during the Fly-By of this Saturnian moon that occurred in late February of the AD 2007. The possibility that those Northern Features, the sizes of small Seas, are either completely or partially filled with Liquid Hydrocarbons has been significantly strengthened also by the Radar Data collected by Cassini and which overlap portions of the Northern Features seen by the Cassini's Imaging Science Subsystem.
Previously, scientists had speculated that Ontario Lacus might simply be a Broad Depression filled by dark, Solid Hydrocarbons falling from the Atmosphere onto Titan’s Surface. In this case, the smoothed outline might be the result of a process unrelated to Rainfall, such as a so-called "Sinkhole" (---> a cavity in the ground, especially in a limestone formation, caused by water erosion and providing a route for Surface Water to disappear) or a "Volcanic Caldera". However, the strong likelihood that the Dark and Smooth North Polar Features are actually Lakes and Seas has made imaging scientists more confident that Ontario Lacus, and the smaller Dark Features dotting the South Polar Regions of Titan, also hold liquid. If correct, this new revelation would mean that each Pole on Titan is, in fact, a large Wetlands Area. The brightest (and almost white) Features seen here (from about 3 to 6 o'clock of the picture), are Methane Clouds (perhaps mixed with Water-Ice Clouds).
The original frame that we show you today, was taken by the NASA - Cassini Spacecraft during the distant Fly-By of Titan that took place in June 6, of the AD 2005, by using a combination of Spectral Filters sensitive to Wavelengths of Polarized InfraRed Light, allowing Cassini to see through the obscuring smog of Titan's Atmosphere and all the way down to the Surface. The image was acquired from an approximate distance of 450.000 Km (such as about 279.450 miles) from Titan. Resolution in the original image is approximately 3 Km (such as 1,863 miles) 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 06241) has been additionally processed and then colorized, as if the yellowish Fogs that surrounds the planet had been overcome. The colorization, even in this case, has been made according to an educated guess 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 South Polar Region of 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 Features seen in this frame would appear, to an average human eye, way lower than it has been shown (better yet: interpreted) here.MareKromium
(2 voti)
|
|
Titan-Lakes-South_Polar_Lake-01-PIA06241-PCF-LXTT-IPF-001.jpgOntario Lacus and the South Polar Regions of Titan (Absolute Natural Colors; credits for the additional process. and color. Dr Paolo C. Fienga/Lunar Explorer Italia/Italian Planetary Foundation)95 visiteThis view of Titan’s South Pole reveals the intriguing Dark Feature named Ontario Lacus and a host of smaller features dotting the whole South Polar Region. The true nature of this Surface Feature, seen here at left of center, is not yet known with absolute certainty. However, the Feature’s extremely dark coloration, the shore-like smoothness of its perimeter, and its presence in an area where frequent Convective Storm Clouds have been observed by the NASA - Cassini Spacecraft and Earth-based telescopes, made it the best candidate for an open body of liquid on Titan when this image was taken, in June 2005. This interpretation has, afterwards, been strengthened by the sighting of Surface Features having similar morphologies, but this time in Titan’s North Polar Regions during the Fly-By of this Saturnian moon that occurred in late February of the AD 2007. The possibility that those Northern Features, the sizes of small Seas, are either completely or partially filled with Liquid Hydrocarbons has been significantly strengthened also by the Radar Data collected by Cassini and which overlap portions of the Northern Features seen by the Cassini's Imaging Science Subsystem.
Previously, scientists had speculated that Ontario Lacus might simply be a Broad Depression filled by dark, Solid Hydrocarbons falling from the Atmosphere onto Titan’s Surface. In this case, the smoothed outline might be the result of a process unrelated to Rainfall, such as a so-called "Sinkhole" (---> a cavity in the ground, especially in a limestone formation, caused by water erosion and providing a route for Surface Water to disappear) or a "Volcanic Caldera". However, the strong likelihood that the Dark and Smooth North Polar Features are actually Lakes and Seas has made imaging scientists more confident that Ontario Lacus, and the smaller Dark Features dotting the South Polar Regions of Titan, also hold liquid. If correct, this new revelation would mean that each Pole on Titan is, in fact, a large Wetlands Area. The brightest (and almost white) Features seen here (from about 3 to 6 o'clock of the picture), are Methane Clouds (perhaps mixed with Water-Ice Clouds).
The original frame that we show you today, was taken by the NASA - Cassini Spacecraft during the distant Fly-By of Titan that took place in June 6, of the AD 2005, by using a combination of Spectral Filters sensitive to Wavelengths of Polarized InfraRed Light, allowing Cassini to see through the obscuring smog of Titan's Atmosphere and all the way down to the Surface. The image was acquired from an approximate distance of 450.000 Km (such as about 279.450 miles) from Titan. Resolution in the original image is approximately 3 Km (such as 1,863 miles) 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 06241) has been additionally processed and then colorized, according to an educated guess 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 South Polar Region of 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 Features seen in this frame would appear, to an average human eye, way lower than it has been shown (better yet: interpreted) here.MareKromium
(2 voti)
|
|
| 426 immagini su 36 pagina(e) |
|
|
|
|
|
30 | |
|
|
|
|
|
|
