Saturn: the "Ringed Beauty" and His Moons
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Saturn-PIA08153.jpgSaturnian Clouds54 visiteLong, thin streamers of cloud arc gracefully across this view of Saturn's Southerly Latitudes.
Analysis of images like this should lead scientists to a new understanding of cloud height variations on this complex gas giant world.
The image was taken in polarized green light with the Cassini spacecraft narrow-angle camera on March 7, 2006, at a distance of approx. 2,9 MKM (about 1,8 MMs) from Saturn. The image scale is 17 Km (about 10 miles) per pixel.
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Saturn-PIA08154.jpgOne "Eye" of Saturn!54 visiteGaseous Saturn rotates quickly - once every approx. 10,8 hours - and its horizontal cloud bands rotate at different rates relative to each other. These conditions can cause turbulent features in the atmosphere to become greatly stretched and sheared, creating the beautiful patterns that the Cassini spacecraft observes. This turbulence and shear is particularly notable at those boundaries where the different bands slide past each other.
Vortices like the one seen here are long-lived dynamical features that are part of the general circulation of Saturn's atmosphere. They are counterparts to the East-West flowing jets and can last for months or years. They probably grow by merging with other vortices until a few dominate a particular shear zone between two jets.
This image was taken in polarized infrared light with the Cassini spacecraft narrow-angle camera on March 7, 2006, at a distance of approximately2,9 MKM (such as about 1,8 MMs) from Saturn. The image scale is 17 Km (about 10 miles) per pixel.
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Saturn-PIA08155.jpgRestless Upper Atmosphere...55 visiteCaption originale:"Streamers, swirls and vortices roll across the dynamic face of Saturn.
Unlike Earth, where most of the weather is driven by the Sun, Saturn's storms and circulation are driven in part by internal heating. Amazingly, the Planet is still contracting (ever so slightly) from its formation, more than 4,5 BY (Billion Years) ago. This gravitational contraction liberates energy in the form of heat.
The image was taken in polarized infrared light with the Cassini spacecraft narrow-angle camera on March 7, 2006, at a distance of approx. 2,9 MKM (1,8 MMs) from Saturn.
The image scale is about 17 Km (roughly 10 miles) per pixel".
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Saturn-PIA08156.jpgCat's Eyes on Saturn!54 visiteCaption originale:"Bright, high altitude clouds, like those imaged here, often appear more filamentary or streak-like than clouds imaged at slightly deeper levels in Saturn's atmosphere. This view also shows one of the many sp-called 'Cat's Eye' vortices that swim through the Southern Latitudes.
The image was taken in polarized infrared light with the Cassini spacecraft narrow-angle camera on March 7, 2006, at a distance of approx. 2,9 MKM (about 1,8 MMs) from Saturn. The image scale is about 17 Km (roughly 10 miles) per pixel".
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Saturn-PIA08159.jpgCrescent Moons (1)56 visiteCaption NASA originale:"The tilted crescent of Saturn displays lacy cloud bands here along with a bright Equatorial Region and threadlike ring shadows on the Northern Hemisphere. Three moons are visible here: Mimas (397 Km, or about 247 miles across) at left and faint, is aligned with the Ring-Plane. At right are Rhea (1.528 Km, or about 949 miles across, at top) and Tethys (1.071 Km, or 665 miles across, below Rhea).
The image was taken in polarized infrared light with the Cassini spacecraft wide-angle camera on March 11, 2006, at a distance of approximately 2,8 MKM (approx. 1,8 MMs) from Saturn.
The image scale is roughly 166 Km (about 103 miles) per pixel".
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Saturn-PIA08161.jpgCrescent Moons (2)56 visiteCaption NASA originale:"Three of Saturn's moons are captured with the Planet in this exquisite family portrait. At top, Saturn is bedecked with the shadows of its innermost rings.
Tethys appears at lower right, closest to Cassini. Janus (181 Km, or about 113 miles across) and Mimas (397 Km, or about 247 miles across) are on the far side of the immense Ringed Planet.
Mimas is just about to slip behind Saturn.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on March 13, 2006, at a distance of approx. 2,7 MKM (such as about 1,6 MMs) from Saturn. The image scale is about 17 Km (approx. 11 miles) per pixel on Janus and Mimas, and 14 about Km (such as about 9 miles) per pixel on Tethys".
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Saturn-PIA08162.jpgSaturnian (swirling) clouds57 visiteCaption NASA originale:"The bright whorls and small-scale specks of convective clouds drift through a Region just North of Saturn's bright Equatorial Band. Observers have seen major storms develop in this Region in the past 15-20 years.
The image was taken in visible red light with the Cassini spacecraft narrow-angle camera on March 13, 2006, at a distance of approximately 2,6 MKM (about 1,6 MMs) from Saturn. The image scale is approx. 15 Km (about 9 miles) per pixel".
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Saturn-PIA08166.jpgRomantic inhospitality...55 visiteCaption originale:"Dreamy colors ranging from pale rose to butterscotch to sapphire give this utterly inhospitable gas planet a romantic appeal. Shadows of the rings caress the Northern Latitudes whose blue color is presumed to be a seasonal effect.
Enceladus hugs the Ring-Plane right of center.
Images taken using red, green and blue spectral filters were combined to create this color view, which approximates what the human eye would see. The image was taken with the Cassini spacecraft wide-angle camera on March 16, 2006 at a distance of approximately 2,1 MKM (such as about 1,3 MMs) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 102°. Image scale is about 120 Km (approx. 75 miles) per pixel on Saturn".
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Saturn-PIA08176.jpgThe "night-side" of Saturn (natural colors)54 visiteThis rare color view of Saturn's night side shows how the Rings dimly illuminate the Southern Hemisphere, giving it a dull golden glow. Part of the Northern dark side is just visible at top - the illumination it receives being far less than the South.
The unlit side of the Rings is shown here. The portion of the Rings closest to Cassini is within the dark shadow of Saturn; the bright distant portion is outside the Planet's shadow.
A crescent Tethys appears below the rings at left.
Images taken using red, green and blue spectral filters were combined to create this color view. The images were taken with the Cassini spacecraft narrow-angle camera on April 2, 2006, at a distance of approx. 3,8 MKM (about 2,4 MMs) from Saturn and 3,5 MKM (about 2,2 MMs) from Tethys. The image scale is about 23 Km (14 miles) per pixel on Saturn.
Cerchiatura Rossa: probabile evidenza di una "Luna Pastore" (Pandora?) o di un "clump" di notevoli dimensioni (optiamo per la "Shepherd Moon").
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Saturn-PIA08190.jpgThrough the Rings...54 visiteCaption NASA originale:"The dark shadows that drape Saturn's Northern Latitudes are split by 3 familiar bright gaps. From bottom to top, Sunlight passes through the broad Cassini Division (4.800 Km - or about 2.980 miles - wide), the Encke Gap (325 Km - or about 200 miles - wide) and (barely visible) the Keeler Gap (42 Km - or about 26 miles - wide).
It is unlikely that the shadows cast by Saturn's Rings have much of an effect on the large-scale movements of the atmosphere. The dynamic clouds of this Gas Giant are driven by processes going on much deeper inside the Planet, where Sunlight does not penetrate.
The image was taken using a spectral filter sensitive to wavelengths of infrared light centered at 752 nanometers. The image was acquired with the Cassini spacecraft wide-angle camera on April 28, 2006 at a distance of approximately 377.000 Km (about 234.000 miles) from Saturn. Image scale is roughly 19 Km (such as about 12 miles) per pixel".
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Saturn-PIA08191.jpgClouds of Saturn54 visiteCaption NASA originale:"The soft, sweeping shadows of Saturn's C-Ring cover bright patches of clouds in the Planet's Atmosphere. The shadow-throwing rings stretch across the view at bottom.
The dark inner edge of the B-Ring is visible at top.
The image was taken using a spectral filter sensitive to wavelengths of infrared light centered at 752 nanometers. The image was acquired with the Cassini spacecraft wide-angle camera on April 28, 2006 at a distance of approximately 340.000 Km (about 211,000 miles) from Saturn. Image scale is roughly 17 Km (about 10 miles) per pixel".
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Saturn-PIA08198.jpgNightflight over Saturn54 visiteCaption NASA originale:"Saturn's atmosphere produces beautiful and sometimes perplexing features. Is the bright feature below center a rare crossing of a feature from a zone to a belt, or is it an illusion created by different cloud layers at different levels? The answer is not always easy to determine.
The image was taken using a spectral filter sensitive to wavelengths of infrared light centered at 938 nanometers.
The image was acquired with the Cassini spacecraft narrow-angle camera on May 12, 2006 at a distance of approx. 2,9 MKM (about 1,8 MMs) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 145°. Image scale is roughly 17 Km (about 10 miles) per pixel".
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