| Ultimi arrivi - Saturn: the "Ringed Beauty" and His Moons |
Saturn-PIA08362.jpgThe Ringed World, from above59 visiteCaption NASA:"Surely one of the most gorgeous sights the Solar System has to offer, Saturn sits enveloped by the full splendor of its stately Rings. Taking in the Rings in their entirety was the focus of this particular imaging sequence. Therefore, the camera exposure times were just right to capture the dark-side of its Rings, but longer than that required to properly expose the globe of sunlit Saturn. Consequently, the sunlit half of the Planet is overexposed.
Between the blinding light of day and the dark of night, there is a strip of twilight on the globe where colorful details in the atmosphere can be seen. Bright clouds dot the bluish-grey Northern Polar Region here. In the South, the Planet's night side glows golden in reflected light from the Rings' sunlit face.
Saturn's shadow stretches completely across the Rings in this view, taken on Jan. 19, 2007, in contrast to what Cassini saw when it arrived in 2004.
The view is a mosaic of 36 images -- that is, 12 separate sets of red, green and blue images -- taken over the course of about 2,5 hours, as Cassini scanned across the entire Main Ring System. This view looks toward the unlit side of the Rings from about 40° above the Ring-Plane.
The images in this natural-color view were obtained with the Cassini spacecraft wide-angle camera at a distance of approx. 1,23 MKM (about 764.000 miles) from Saturn. Image scale is roughly 70 Km (about 44 miles) per pixel".MareKromiumMar 02, 2007
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Saturn-PIA08357.jpgCrescent Saturn58 visiteCaption NASA:"Cassini coasts beneath giant Saturn, staring upward at its gleaming crescent and icy rings.
A great bull's-eye pattern is centered on the South Pole, where a vast, hurricane-like storm spins.
This view looks toward the lit side of the Rings from about 26° below the Ring-Plane. The view was acquired about 2 hours prior to "The Lore of Saturn".
Images taken using red, green and blue spectral filters were combined to create this natural-color view.
The images were obtained with the Cassini spacecraft wide-angle camera on Jan. 30, 2007, from a distance of approx. 1,1 MKM (about 700.000 miles) from Saturn.
Image scale is roughly 61 Km (about 38 miles) per pixel".MareKromiumMar 02, 2007
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Saturn-PIA08358.jpgThe Northern Regions of Saturn60 visiteCaption NASA:"Magnificent blue and gold Saturn floats obliquely as one of its gravity-bound companions, Dione, hangs in the distance. The darkened Rings seem to nearly touch their shadowy reverse images on the planet below.
This view looks toward the unlit side of the Rings from about 9° above the Ring-Plane. The Rings glow feebly in the scattered light that filters through them.
The image was taken in visible light with the Cassini spacecraft wide-angle camera on Feb. 4, 2007, at a distance of approx. 1,2 MKM (about 800.000 miles) from Saturn.
Image scale is roughly 75 Km (about 47 miles) per pixel".MareKromiumMar 02, 2007
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Saturn-PIA08359.jpgThe Southern Regions of Saturn58 visiteCaption NASA:"With pastel blues, pinks, greens and golds, Saturn displays a dazzling diversity of colors and hues.
Here, Cassini looks upward at, and through, the sunlit side of the Rings from about 19° below the Ring-Plane. The small moon Janus can be spotted off the Planet's Western Limb (edge) near the image bottom.
Images taken using red, green and blue spectral filters were combined to create this natural-color view. The images were obtained with the Cassini spacecraft wide-angle camera on Feb. 3, 2007, at a distance of approx. 1,1 MKM (about 700.000 miles) from Saturn.
Image scale is roughly 60 Km (about 38 miles) per pixel".MareKromiumMar 02, 2007
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Saturn-PIA08360.jpgFrom North to South...58 visiteCaption NASA:"Dark and sharply defined ring shadows appear to constrict the flow of color from Saturn's warmly hued South to the bluish Northern Latitudes.
Scientists studying Saturn are not yet sure about the precise cause of the color change from North to South. NASA Voyager spacecraft flybys witnessed a more evenly painted Planet in the early '80s, when Saturn was closer to Equinox. However, the bluish color was readily apparent upon Cassini's approach to the Planet in late 2003, when Saturn was just coming out of its Northern Hemisphere Winter. Scientists have speculated that the color is due to seasonal effects on the atmosphere.
Aside from the color differences, the cloud morphology is quite different in the Polar Regions compared to the mid-latitudes. Bright, isolated clouds dot the high latitudes, while Saturn's middle is characterized by flowing cloud bands and the occasional bright or dark vortex.
This view looks toward the lit side of the rings from about half a degree below the Ring-Plane.
Images taken using red, green and blue spectral filters were combined to create this natural-color view. The images were obtained with the Cassini spacecraft wide-angle camera on Feb. 4, 2007, at a distance of approx. 1,2 MKM (about 700.000 miles) from Saturn. Image scale is roughly 67 Km (about 42 miles) per pixel". MareKromiumMar 02, 2007
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Saturn-PIA08361.jpgThe Ring-World in natural colors57 visiteCaption NASA:"Our robotic emissary, flying high above Saturn, captured this view of an alien copper-colored Ring-World. The overexposed planet has deliberately been removed to show the unlit Rings alone, seen from an elevation of 60°, the highest Cassini has yet attained.
The view is a mosaic of 27 images -- nine separate sets of red, green and blue images -- taken over the course of about 45', as Cassini scanned across the entire main Ring System. The Planet's shadow carves a dark swath across the Ring-Plane at the right.
Moons visible in this image: Epimetheus, at the 1 o'clock position; Pandora, at the 5 o'clock position and Janus, at the 10 o'clock position.
Bright clumps of material in the narrow F-Ring moved in their orbits between each of the color exposures, creating a chromatic misalignment that provides some sense of the continuous motion in the Ring System.
Radially extending lens flare artifacts, which result from light being scattered within the camera optics, are present in the view.
The images in this natural-color view were obtained with the Cassini spacecraft wide-angle camera on Jan. 21, 2007, at a distance of approx. 1,6 MKM (1 MMs) from Saturn. Image scale is 90 roughly Km (about 56 miles) per pixel".
MareKromiumMar 02, 2007
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The_Rings-PIA08887.jpgHeading to the Darkness57 visiteCaption NASA:"This strikingly crisp view shows Atlas heading into Saturn's shadow at upper left. The moon's basic, elongated shape is easy to detect here. Above Atlas, a bright clump in the F-Ring also heads toward the darkness. This view looks toward the unlit side of the Rings from about 30° above the Ring-Plane.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Jan. 19, 2007 at a distance of approx. 1,2 MKM (about 700.000 miles) from Atlas. Image scale is roughly 7 Km (about 4 miles) per pixel".Mar 01, 2007
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Rhea-PIA08886.jpgDrawing Out Details on Rhea59 visiteRhea displays a marked color contrast from North to South that is particularly easy to see in the extreme color-enhanced Cassini spacecraft view presented here.
A clear filter image is also presented (left) alongside the color composite (right).
To create the false-color view, ultraviolet, green and infrared images were combined into a single picture that isolates and maps regional color differences.
This "color map" was then superimposed over a clear-filter image that preserves the relative brightness across the body.
The combination of color map and brightness image shows how colors vary across the surface of Rhea. The origin of the color differences is not yet understood, but may be caused by subtle differences in the surface composition or the sizes of grains making up the icy surface material.
This view looks toward the Trailing Hemisphere on Rhea. The view shows southerly latitudes on Rhea, down to the South Pole. North is up and rotated 17° to the right.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Jan. 17, 2007 at a distance of approx. 457.000 Km (about 284.000 miles) from Rhea.
Image scale is roughly 3 Km (a little less than 2 miles) per pixel.
Mar 01, 2007
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Tethys-PIA07693.jpgOdysseus (elab. Lunexit)58 visitenessun commentoMareKromiumFeb 28, 2007
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Saturn-PIA08883.jpgSaturn's South Polar Regions (near Natural Colors - elab. NASA)57 visiteCaption NASA:"The Cassini spacecraft views Saturn's Southern Latitudes in color, spying a great, eye-shaped vortex just northward of the South Polar Region. Other dark vortices, common features of Saturn's general circulation, are visible in the Mid-Latitudes.
Contrast in the image was enhanced to make features in the atmosphere more visible.
Images taken using red, green and blue spectral filters were combined to create this near-natural color view. The images were taken in visible light with the Cassini spacecraft wide-angle camera on Jan. 14, 2007 at a distance of approx. 958.000 Km (such as about 595.000 miles) from Saturn.
Image scale is roughly 54 Km (about 33 miles) per pixel".MareKromiumFeb 24, 2007
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The_Rings-PIA08882.jpgDisturbances...56 visiteCaption NASA:"Daphnis cruises through the Keeler Gap, raising edge waves in the ring material as it passes.
As is characteristic of waves raised by a moon on the edges of a very narrow gap like Keeler, the wave begins as a coherent form near Daphnis and becomes less so with increasing orbital distance from the moon. Daphnis is about 7 Km (4,3 miles) across.
This view looks upon the lit side of the Rings from about 31° below the Ring-Plane.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Jan. 17, 2007 at a distance of approx. 768.000 Km (about 477.000 miles) from Daphnis. Image scale is roughly 5 Km (about 3 miles) per pixel".MareKromiumFeb 24, 2007
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The_Rings-PIA08878.jpgThe "F-Ring", sinking in the shadows... (elab. Lunexit)69 visiteCaption NASA:"The strands of Saturn's F-Ring disappear into the darkness of the Planet's shadow.
Background stars make trails across the sky during the long exposure. This view looks toward the unlit side of the Rings from about 55° above the Ring-Plane.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Jan. 3, 2007 at a distance of approx. 1,4 MKM (such as about 900.000 miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 108°.
Image scale is roughly 8 Km (about 5 miles) per pixel".Feb 20, 2007
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