Saturn: the "Ringed Beauty" and His Moons
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Saturn-PIA11396.jpgSouth Polar Aurora on Saturn54 visiteCaption NASA:"This image of the North Polar Regions of Saturn shows both the Aurora and underlying Atmosphere, seen at 2 different wavelengths of IR light as captured by NASA's Cassini spacecraft.
Energetic particles, crashing into the Upper Atmosphere cause the Aurora, shown in blue, to glow brightly at 4 microns (six times the wavelength visible to the human eye). The image shows both a bright ring, as seen from Earth, as well as an example of bright Auroral Emission within the Polar Cap that had been undetected until the advent of Cassini.
This Aurora, which defies past predictions of what was expected, has been observed to grow even brighter than is shown here. Silhouetted by the glow (cast here to the color red) of the hot interior of Saturn (clearly seen at a wavelength of 5 microns, or seven times the wavelength visible to the human eye) are the clouds and haze that underlie this Auroral Region. For a similar view of the Region beneath the Aurora see PIA09185.
This image is a composite captured with Cassini's Visual and Infrared Mapping Spectrometer. The aurora image was taken in the near-infrared on Nov. 10, 2006, from a distance of about 1 MKM (such as about 659.000 miles), with a phase angle of 157° and a sub-Spacecraft Planetocentric Latitude of 52° North.
The image of the clouds was obtained by Cassini on June 15, 2008, from a distance of approx. 602.000 Km (such as about 374.000 miles) and a sub-Spacecraft Planetocentric Latitude of 73° North".MareKromium
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Saturn-PIA11453.jpgShadows (Natural Colors; credits: NASA/JPL/Space Science Institute)55 visiteCaption NASA:"Saturn's Rings cast a dramatic shadow separating the blues and greens of the Planet's Northern Hemisphere from the creamy pastels coloring the Southern Hemisphere.
This mosaic combines 6 images — 2 each of red, green and blue spectral filters — to create this Natural Color view. The images were obtained with the Cassini Spacecraft wide-angle camera on Dec. 30, 2008 at a distance of approx. 1,2 MKM (such as about 750.000 miles) from Saturn and at a Sun-Saturn-Spacecraft, or Phase, Angle of 30°.
Image scale is roughly 67 Km (about 42 miles) per pixel".MareKromium
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Saturn-PIA11461.jpgBlack Shadow from the "White Moon" (Natural Colors; credits: Lunar Explorer Italia)54 visiteCaption NASA:"The shadow of Saturn's moon Enceladus cast onto the Planet's Atmosphere appears like a drop of black ink on a canvas of Saturnian storms.
The image was taken with the Cassini spacecraft narrow-angle camera on June 20, 2008 using a spectral filter sensitive to wavelengths of Near-InfraRed Light centered at 750 nanometers. The view was obtained at a distance of approx. 1,3 MKM (such as about 810.000 miles) from Saturn and at a Sun-Saturn-Spacecraft, or Phase, Angle of 24°.
Image scale is roughly 7 Km (about 4 miles) per pixel".MareKromium
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Saturn-PIA11464.jpgDaybreak from above55 visiteCaption NASA:"Day breaks on the Northern Hemisphere of Saturn in this image from Cassini. The D-Ring is hidden below the horizon, but, working outward from the Planet, this image shows the C, B, A and F-Rings. The moon Prometheus is a faint speck inside the thin F-Ring in the upper left of the image.
This view looks toward the unilluminated side of the Rings from about 39° above the Ring-Plane. The image was taken with the Cassini Spacecraft wide-angle camera on March 20, 2009 using a spectral filter sensitive to wavelengths of Near-InfraRed Light centered at 853 nanometers.
The view was obtained at a distance of approx. 888.000 Km (such as about 552.000 miles) from Saturn and at a Sun-Saturn-Spacecraft, or Phase, Angle of 121°.
Image scale is roughly 50 Km (about 31 miles) per pixel".MareKromium
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Saturn-PIA11473.jpgThe Northern Region of Saturn (Natural Colors; credits: NASA/JPL/Space Science Institute)63 visiteCaption NASA:"Saturn's Northern Hemisphere is seen here against its nested Rings.
This view from the Cassini Spacecraft looks toward the unilluminated side of the Rings from about 30° above the Ring-Plane. The rings have been brightened relative to the Planet to enhance visibility.
Images taken using red, green and blue spectral filters were combined to create this Natural Color view.
The images were acquired with the Cassini Spacecraft wide-angle camera on Feb. 24, 2009 at a distance of approx. 866.000 Km (about 538.000 miles) from Saturn.
Image scale is roughly 38 Km (about 24 miles) per pixel".MareKromium
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Saturn-PIA11478.jpgTransparencies (Natural Colors; credits: NASA/JPL/Space Science Institute)61 visiteCaption NASA:"This Natural Color view from the Cassini Spacecraft highlights the myriad gradations in the transparency of Saturn's inner Rings.
The dark shadows of the Rings separate Saturn's Southern Hemisphere in the bottom of the image from the North. The innermost D-Ring is invisible, laid over the Planet's Northern Hemisphere. The translucent C-Ring runs through the middle of the image. The denser B-Ring stretches across the top of the image.
This view looks toward the sunlit side of the Rings from about 48° below the Ring-Plane. Images taken using red, green and blue spectral filters were combined to create this Natural Color view. The images were acquired with the Cassini Spacecraft wide-angle camera on Feb. 28, 2009 at a distance of approx. 1 MKM (about 620.000 miles) from Saturn.
Image scale is roughly 59 Km (approx. 37 miles) per pixel".MareKromium
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Saturn-PIA11493.jpgBetween Day and Night... (Natural Colors; credits: NASA/JPL/Space Science Institute)65 visiteCaption NASA:"Rays of light from the Sun have taken many different paths to compose this glorious image of Saturn and its Rings.
This view looks toward the unilluminated (North) side of the Rings and, at the top of the image, the night side of Saturn. Sunlight has been reflected off the illuminated side of the Rings to light the Planet's Southern Hemisphere, seen here as a bright band of yellow-orange.
The Northern Hemisphere, in the top left corner of the image, is dimly lit by light diffusely scattered through the rings. The Planet's shadow cuts across the Rings, but light reflected off the Southern Hemisphere backlights parts of the C-Ring, making them visible in silhouette. Bright points of light in the image are stars occulted by the Rings.
This view looks toward the unilluminated side of the Rings from about 41° above the Ring-Plane. Images taken using red, green and blue spectral filters were combined to create this Natural Color view. The images were acquired with the Cassini Spacecraft wide-angle camera on March 20, 2009 at a distance of approx. 892.000 Km (such as about 554.000 miles) from Saturn.
Image scale is roughly 50 Km (about 31 miles) per pixel".MareKromium
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Saturn-PIA11513.jpgSouthern Colors (Natural Colors; credits: NASA/JPL/Space Science Institute)67 visiteCaption NASA:"The Cassini Spacecraft samples a bit of Saturn's Southern Hemisphere along with a spread of the Planet's main Rings.
Working outward from the Planet, the C, B, and A-Rings are visible in this Natural Color image. The Rings have been brightened relative to the Planet to enhance their visibility.
This view looks toward the sunlit side of the Rings from about 59° below the Ring-Plane. Images taken using red, green and blue spectral filters were combined to create this Natural Color view.
The images were acquired with the Cassini Spacecraft wide-angle camera on April 23, 2009 at a distance of approx. 1 MKM (about 621.000 miles) from Saturn.
Image scale is roughly 58 Km (approx. 36 miles) per pixel".MareKromium
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Saturn-PIA11518.jpgApproaching the Equinox73 visiteCaption NASA:"The shadow of the moon Mimas has just slipped off Saturn's Rings and onto the Planet in this Cassini Spacecraft image. The shadow is visible as a short dash below the Rings' shadows on the Planet. At this exposure setting, the Rings are too dim to be seen easily. As Saturn approaches its August 2009 equinox, the Planet's moons cast shadows onto the Rings.
This view looks toward the unilluminated side of the Rings from about 61° above 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 April 30, 2009 at a distance of approx. 1,4 MKM (about 870.000 miles) from Saturn.
Image scale is roughly 80 Km (about 50 miles) per pixel".MareKromium
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Saturn-PIA11613.jpgPost-Equinox Colors (Natural Colors; credits: NASA/JPL/Space Science Institute)66 visiteCaption NASA:"The Cassini Spacecraft captured this Natural Color View of Saturn almost a month after the Planet's August 2009 Equinox. The shadow cast on the Planet by the Rings remains narrow.
Spokes are visible on the B-Ring. To learn more about these ghostly radial structures, see PIA11144.
Mimas (approx. 396 Km, or about 246 miles across) can be seen in the lower left. Mimas and the Rings have been brightened relative to the Planet to increase visibility.
The novel illumination geometry that accompanies Equinox lowers the Sun's angle to the Ring-Plane, significantly darkens the Rings, and causes out-of-plane structures to look anomalously bright and cast shadows across the Rings. These scenes are possible only during the few months before and after Saturn's Equinox, which occurs only once in about 15 Earth years.
Before and after Equinox, Cassini's cameras have spotted not only the predictable shadows of some of Saturn's moons (see PIA11657), but also the shadows of newly revealed vertical structures in the Rings themselves (see PIA11665).
This view looks toward the Northern, sunlit side of the Rings from about 10° above the Ring-Plane.
The red, green and blue images that were mosaicked together to create this view were obtained with the Cassini Spacecraft wide-angle camera on Sept. 4, 2009. The view was obtained at a distance of approx. 2,7 MKM (such as about 1,7 MMs) from Saturn and at a Sun-Saturn-Spacecraft, or Phase, Angle of 92°.
Image scale is roughly 156 Km (about 97 miles) per pixel".MareKromium
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Saturn-PIA11633.jpgShadows...55 visiteCaption NASA:"The shadows of two moons appear on Saturn, above and below the plane of the Planet's Rings.
North on Saturn is up in this image, and the shadow of Dione can be seen south of the Planet's Equator. The smaller shadow of Mimas is north of the Equator.
Dione and Mimas both have orbits that are slightly inclined in relation to the Planet's Equatorial Plane, so, depending upon the orientation of their orbits, their shadows may appear North or South of Saturn's Equator. The moons themselves do not appear in this image.
This view looks toward the Northern, sunlit side of the Rings from about 1° above the Ring-Plane. Scale in the original image was about 100 Km (approx. 62 miles) per pixel. The image has been magnified by a factor of 1.5 and contrast-enhanced to aid visibility.
The image was taken with the Cassini Spacecraft wide-angle camera on Oct. 15, 2009 using a spectral filter sensitive to wavelengths of Near-InfraRed Light centered at 752 nanometers. The view was acquired at a distance of approx. 899.000 Km (about 558.000 miles) from Saturn and at a Sun-Saturn-Spacecraft, or Phase, angle of 65°".MareKromium
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Saturn-PIA11640.jpgNarrow Shadow55 visiteCaption NASA:"From just above the Plane of Saturn's Rings, the Cassini Spacecraft snapped this shot of Saturn two months after Saturn's August 2009 Equinox, showing the shadow of its Rings as a narrow band on the Planet.
Cassini is looking toward the sunlit side of the rings from about 1° above the Ring-Plane.
The novel illumination geometry that accompanies Equinox lowers the Sun's angle to the Ring-Plane, significantly darkens the Rings, and causes out-of-plane structures to look anomalously bright and cast shadows across the Rings. These scenes are possible only during the few months before and after Saturn's Equinox, which occurs only once in about 15 Earth years.
Before and after Equinox, Cassini's cameras have spotted not only the predictable shadows of some of Saturn's moons (see, for instance, PIA11657), but also the shadows of newly revealed Vertical Structures in the Rings themselves (see PIA11665).
The image was taken with the Cassini Spacecraft wide-angle camera on Oct. 16, 2009 using a spectral filter sensitive to wavelengths of Near-InfraRed Light centered at 752 nanometers. The view was obtained at a distance of approx. 1,5 MKM (such as about 932.000 miles) from Saturn and at a Sun-Saturn-Spacecraft, or Phase, Angle of 83°.
Image scale is roughly 86 Km (approx. 53 miles) per pixel".MareKromium
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