| |
| Ultimi arrivi - Saturn: the "Ringed Beauty" and His Moons |
Saturn-W00017984.jpgWhat do some images show? (2)98 visitenessun commentoSet 19, 2006
|
|
Saturn-W00017983.jpgWhat do these images show? (1)59 visitenessun commentoSet 19, 2006
|
|
Saturn-W00018094.jpgOverexposed F-Ring, a few Stars and some Image-Artifacts58 visitenessun commentoSet 19, 2006
|
|
Saturn-PIA08271.jpgThe "Ringed Beauty" in natural colors58 visiteCaption NASA originale:"This moody true color portrait of Saturn shows a world that can, at times, seem as serene and peaceful as it is frigid and hostile. Saturn's unlit-side Rings embrace the Planet while their shadows caress the Northern Hemisphere.
The view was obtained from about 15° above the Ring-Plane as Cassini continued its climb to higher orbital inclinations.
Images taken using red, green and blue spectral filters were combined to create this natural color view. The image was acquired with the Cassini spacecraft wide-angle camera on Aug. 18, 2006 at a distance of approximately 1,3 MKM (such as about 800.000 miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 137°.
Image scale is roughly 76 Km (about 47 miles) per pixel".Set 18, 2006
|
|
The Rings-W00017896.jpgAn enormous "clump" in Saturn's Rings? No: that's Enceladus!57 visiteCaption NASA:"W00017896.jpg was taken on September 15, 2006 and received on Earth September 17, 2006. The camera was pointing toward the Rings of Saturn that, at the time, were approximately 2.227.319 Km away.
The image was taken using the CL1 and IRP90 filters. This image has not been validated or calibrated".
Wispy fingers of bright, icy material reach tens of thousands of kilometers outward from Saturn's moon Enceladus into the E-Ring, while the moon's active South Polar jets continue to fire away. This astonishing, never-before-seen structure is made visible with the Sun almost directly behind the Saturn System from Cassini's vantage point. The phase angle here is 175°, a viewing geometry in which structures made of tiny particles brighten substantially. These features are very likely the result of particles injected into Saturn orbit by the Enceladus geysers: those injected in the direction of the moon's orbital motion end up on larger, slower orbits and trail Enceladus in its orbit, and those injected into the opposite direction end up smaller, faster orbits and lead Enceladus. (Orbital motion is counter-clockwise.) In addition, the configuration of wisps may hint at an interaction between Saturn's magnetosphere and the torrent of particles issuing from Enceladus.
In addition to the wisps, another unexpected detail is the dark gore in the center of the ring, following the moon in its orbit, likely brought about by the sweeping action of Enceladus as it orbits in the center of the E ring.
The view looks down onto Enceladus (505 kilometers, or 314 miles across) from about 15 degrees above the ringplane. Tethys (1,071 kilometers, or 665 miles across) is visible to the left of Enceladus.
The image was taken in visible light with the Cassini spacecraft wide-angle camera on Sept. 15, 2006, at a distance of approximately 2.1 million kilometers (1.3 million miles) from Enceladus. Image scale is 128 kilometers (80 miles) per pixel.
Set 18, 2006
|
|
Saturn-W00017924.jpgRising Sun...57 visiteCaption NASA:"W00017924.jpg was taken on September 15, 2006 and received on Earth September 17, 2006. The camera was pointing toward Saturn that, at the time, was approximately 2.092.473 Km away.
The image was taken using the CB3 and CL2 filters. This image has not been validated or calibrated".Set 18, 2006
|
|
Saturn-PIA08735.jpgThree, for one and the same: Saturn, in infrared light60 visiteCaption NASA:"This false-color image of Saturn was constructed by combining 3 images at 3 different infrared wavelengths.
The image at the upper left was taken at 1,3 microns, where both Saturn and its Rings strongly reflect light. The center image in the top panel was taken at 2,4 microns, where the Rings strongly reflect light, but Saturn, because of the methane in its atmosphere, absorbs most of the light. The third image on the right in the panel was taken at a wavelength of 5 microns where, because they are composed of almost pure water ice, the Rings absorb almost all the light, and Saturn, because its interior is warm, glows. Assigning each of the three images to blue, green and red, respectively, results in the beautiful, false-color, composite image shown here.
These images were taken on June 21, 2004, with Cassini's VIMS (Visual and Infrared Mapping Spectrometer) from a distance of approx. 6,35 MKM (about 3,94 MMs) from Saturn".Set 16, 2006
|
|
Helene-PIA08269.jpgMoments of "Helene"59 visiteCaption NASA originale:"This set of images exposes details on small and crumpled-looking Helene. Large portions of this Trojan moon of Dione appear to have been blasted away by impacts.
Cassini passed within 50.000 Km (about 31,000 miles) of Helene (which is about 32 Km - or 20 miles across) on Aug. 17, 2006, when these images were acquired.
The views were obtained over the course of an hour and are presented here in reverse order (i.e.: the leftmost image was taken latest).
The images were taken in visible light with the Cassini spacecraft narrow-angle camera. As presented here, the views were acquired at distances ranging from about 62.000 to 51.000 Km (such as about 39.000 to 32.000 miles) from Helene and at a Sun-Helene-spacecraft, or phase, angle of 111 to 120°. Image scale is roughly 375 to 300 meters (approx. 1.230 to 984 feet) per pixel, from left to right".Set 15, 2006
|
|
Saturn-PIA08734.jpgInner Warmth, Hidden Light...57 visiteCaption NASA originale:"This false-color image of Saturn shows Ring shadows running across the upper portion of the Planet, and sunlight illuminating the lower portion of the Planet.
The upper area, in the Ring shadow, would be black in visible light but glows red in infrared because Saturn is warm inside. This light shines out through the clouds, giving scientists a look at some of Saturn's interesting atmospheric structure.
This image was taken on June 30, 2006, with Cassini's VIMS. It was constructed from images taken at wavelengths of 0,91 microns (blue); 2,25 microns (green) and at 5,01 (red).
The distance from Cassini to Saturn's center in this image is aspprox. 335.000 Km (about 208.159 miles)".Set 14, 2006
|
|
Dione-PIA08266.jpgThe Night-Side of Dione, in the Saturnshine58 visiteCaption NASA originale:"Cassini whizzed past Dione on Aug. 16, 2006, capturing this slightly motion-blurred view of the moon's fractured and broken landscape in reflected light from Saturn. The motion blur is a result of the long exposure time used to capture dim light from the moon's night side.
The many canyons on Dione rip through more ancient craters. Some medium-sized craters, like the one right of center, have several others overprinted onto them. This view shows southern terrain on the moon's Trailing Hemisphere. The gleaming, sunlit crescent is overexposed at bottom. North is up.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera at a distance of approx. 157.000 Km (about 98.000 miles) from Dione and at a Sun-Dione-spacecraft angle of 129°.
Image scale is about 935 mt (roughly 3.067 feet) per pixel".Set 14, 2006
|
|
Daphnis-PIA07809-2.jpgDaphnis and Keeler (detail mgnf)116 visitenessun commentoSet 13, 2006
|
|
Daphnis-PIA07809-1.jpgDaphnis and Keeler (context image)58 visiteCaption NASA originale:"Daphnis, the tiny moon that inhabits the Keeler Gap in the outer edge of Saturn's A-Ring, is captured here in remarkable detail with its entourage of waves.
The edge waves are especially bright in places where Ring material piles up, a characteristic that has been seen in computer simulations of the interactions between gap-embedded moons and the surrounding ring particles.
The 7 Km-wide (about 4,3 mile) moon appears to have an unusual shape in this image. It is not simply a bright dot, but instead exhibits a dimmer component immediately to its left. Though it is far from certain, this component may be Ring material caught in the act of accreting onto Daphnis, a process currently being studied by imaging scientists.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Sept. 9, 2006, at a distance of approx. 422.000 Km (such as about 262.000 miles) from Saturn. Image scale is roughly 2 Km (a little more than 1 mile) per pixel".Set 13, 2006
|
|
| 2245 immagini su 188 pagina(e) |
|
|
|
|
|
96 | |
|
|
|
|
|
|
