| Ultimi arrivi - Saturn: the "Ringed Beauty" and His Moons |
Enceladus-PIA20522enceladusC.jpgCrescent Enceladus (Credits: NASA/JPL/Cassini Imaging Team)123 visitePeering from the shadows, the Saturn-facing hemisphere of tantalizing inner moon Enceladus poses in this Cassini spacecraft image. North is up in the dramatic scene captured during November 2016 as Cassini's camera was pointed in a nearly sunward direction about 130,000 kilometers from the moon's bright crescent. In fact, the distant world reflects over 90 percent of the sunlight it receives, giving its surface about the same reflectivity as fresh snow. A mere 500 kilometers in diameter, Enceladus is a surprisingly active moon. Data and images collected during Cassini's flybys have revealed water vapor and ice grains spewing from south polar geysers and evidence of an ocean of liquid water hidden beneath the moon's icy crust.MareKromiumDic 31, 2023
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ZZ-Falling_on_Saturn.jpgEnd of Mission (Artistic View)278 visitenessun commentoMareKromiumOtt 15, 2023
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Atlas-1.jpgAtlas91 visitenessun commentoMareKromiumAgo 02, 2022
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Tethys.pngTethys and the Sun (possible Natural Colors; credits for the additional process. and color.: Marco Faccin and E. Bonora)106 visitenessun commentoMareKromiumFeb 10, 2021
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Epimetheus-PIA21335.jpgEpimetheus114 visitenessun commentoMareKromiumOtt 25, 2020
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Atlas.jpgAtlas (Credits: Dr Marco Faccin and Elisabetta Bonora)184 visitenessun commentoMareKromiumSet 04, 2020
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Pandora.pngPandora: nice and close (Credits: Dr Marco Faccin and Elisabetta Bonora)136 visiteUnbelievable view.MareKromiumSet 04, 2020
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Saturn-PIA21899.gifPolar Lights (Auroral Emissions from the North Pole of Saturn)112 visiteCaption NASA Originale:"On Sept. 14, 2017, one day before making its final plunge into Saturn's Atmosphere, NASA's Cassini Spacecraft used its Ultraviolet Imaging Spectrograph, or UVIS, instrument to capture this final view of Ultraviolet Auroral Emissions over the Planet's North Polar Regions.
The view is centered on the North Pole of Saturn, with lines of Latitude visible for 80, 70 and 60°. Lines of Longitude are spaced 40° apart. The Planet's Day-Side is at the bottom of the picture, while the Night-Side is at the top. A sequence of images from this observation has also been assembled into a movie sequence. The last image in the movie was taken about an hour before the still image, which was the actual final UVIS auroral image.
Auroral Emissions are generated by charged particles traveling along the invisible lines of Saturn's Magnetic Field. These particles (then) precipitate into the Atmosphere, releasing light when they strike (the) Gas Molecules (that are present) there.
Several individual auroral structures are visible here, despite that this UVIS view was acquired at a fairly large distance from the Planet (such as about 424.000 miles or approx. 682.361,856 Km). Each of these features is connected to a particular phenomenon (occurring) in the Saturnian Magnetosphere. For instance, it is possible to identify Auroral "signatures" here that are related to the injection of "Hot Plasma" from the Day-Side Magnetosphere, as well as Auroral Features associated with a change in the Magnetic Field's shape (existing) on the Magnetosphere's Night-Side.
Several possible scenarios have been postulated over the years to explain Saturn's changing Auroral Emissions, but researchers are still far from a complete understanding of this complicated puzzle. Researchers will continue to analyze the hundreds of image sequences UVIS obtained of Saturn's auroras during Cassini's 13-year mission, with many new discoveries likely to be made.
This image and movie sequence were produced by the Laboratory for Planetary and Atmospheric Physics (LPAP) of the STAR Institute of the University of Liege in Belgium, in collaboration with the UVIS Team".MareKromiumMar 12, 2020
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Atlas,_Daphins_and_Pan-PIA21449.jpgAtlas, Daphnis and Pan155 visiteCaption NASA:"This montage of views from NASA's Cassini Spacecraft shows three of Saturn's Small Ring moons: Atlas, Daphnis and Pan at the same scale for ease of comparison.
Two differences between Atlas and Pan are obvious in this montage. Pan's Equatorial Band is much thinner and more sharply defined, and the central mass of Atlas (the part underneath the smooth Equatorial Band) appears to be smaller than that of Pan.
All of these images were taken using the Cassini Spacecraft Narrow-Angle Camera. The images of Atlas were acquired on April 12, 2017, at a distance of about 10.000 miles (approx. 16,0093 Km) and at a Sun-moons-Spacecraft angle (or Phase Angle) of 37°. All three images are oriented so that North is up".MareKromiumGen 23, 2020
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Saturn-PIA21895.jpgFarewell Cassini...144 visiteCaption NASA:"This Natural Color view view is the last image taken by the imaging cameras on NASA's Cassini Spacecraft. It looks toward the planet's night side, lit by reflected light from the Rings, and shows the location at which the Spacecraft would enter the Planet's Atmosphere a few hours later.
ThE view was created by using images taken with red, green and blue spectral filters. The imaging cameras obtained the view at approximately the same time that Cassini's Vsual and InfraRed Mapping Spectrometer made its own observations of the impact area in the thermal infrared.
This location - the site of Cassini's atmospheric entry - was at this time on the night side of the Planet, but would rotate into daylight by the time Cassini made its final dive into Saturn's Upper Atmosphere, ending its remarkable 13-year exploration of Saturn.
The view was acquired on Sept. 14, 2017 at 19:59 UTC (spacecraft event time). The view was taken in Visible Light using the Cassini Spacecraft Wide-Angle Camera at a distance of about 394.000 miles (such as roughly 634.081 Km) from Saturn. Image scale is about 11 miles (about 17,7 Km). The original image has a size of 512 x 512 pixels".MareKromiumGen 23, 2020
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Saturn-PIA21903-01.jpgThe End....114 visitenessun commentoMareKromiumGen 23, 2020
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Saturn-PIA21903-00.jpgThe End....105 visiteCaption NASA originale:"This view of Saturn looks toward thePplanet's Night Side, only lit by Sunlight reflected from the Rings.
A mosaic of some of the very last images captured by Cassini's cameras, shows the location where the Spacecraft would have entered the Planet's Atmosphere a few hours later. An annotated view (see the next frame) marks the entry site with an oval. While this area was on the Night Side of the Planet at the time, it would rotate into daylight by the time Cassini made its final dive into Saturn's Upper Atmosphere, ending its remarkable 13-year exploration of Saturn.
Images taken using red, green and blue spectral filters were combined to show the scene in Near Natural Colors. The images were taken with Cassini's wide-angle camera on Sept. 14, 2017, at a distance of approx. 394.000 miles (such as a little more than 634.000 Km) from Saturn.
The Cassini spacecraft ended its mission on Sept. 15, 2017".MareKromiumGen 23, 2020
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