Saturn: the "Ringed Beauty" and His Moons
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Rhea-W00034595.jpgRhea (natural colors: elab. Lunexit)54 visiteCaption NASA:"W00034595.jpg was taken on August 30, 2007 and received on Earth August 30, 2007. The camera was pointing toward RHEA that, at the time, was approx. 19.446 Km away, and the image was taken using the CL1 and VIO filters. This image has not been validated or calibrated".MareKromium
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Rhea.jpgRhea in "strange" colors72 visiteAbbiamo intitolato questa immagine "Rhea in colori strani" ma, a ben vedere, avremmo forse fatto meglio a scrivere "Rhea falsa". Questa ripresa di Rhea è, in effetti - ed a quanto ci è dato sapere - completamente unica. Il colorito azzurrino e quelle formazioni frastagliate bianche che attraversano l'intero Pianeta (e che assomigliano a nuvole) non sono visibili in nessun altra fotografia di questa Luna di Saturno. Si tratta dunque di un falso? O forse di un errore occorso durante l'attività di processo del frame originale? Cattivi abbinamenti cromatici? Potremmo andare avanti per pagine, senza arrivare a nulla. L'unica cosa che si può dire, ad oggi, è che Rhea, agli occhi di Voyager o di Cassini/Huygens (ed ai nostri occhi), appare - di regola! - in maniera completamente differente. L'unica cosa che possiamo fare è aspettare nuove immagini a colori per tentare di vederci più chiaramente.
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Rhea.jpgTirawa Basin on Reha, from Voyager 1 (Natural Colors; credits: Ted Stryk)54 visiteAs Voyager 1 receded from its close flyby of Rhea, it snapped this view of Rhea's Tirawa Basin, a large impact structure seen on the Terminator in this crescent view.
It is on of the worst-imaged parts of this world, and this Voyager view is still the best. Rhea is a moon that shows some similar features to more active Dione and Tethys, but seems to have been inactive for longer, as evidenced by the fact that all of its surface is extremely worn from impacts and the evidences of internal activity are much more subtle.MareKromium
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Rhea2-EB-LXTT.jpgDo dimensions count? (an Image-Mosaic in Natural Colors by Elisabetta Bonora - Lunexit Team)76 visitenessun commentoMareKromium
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Rhea_Dione-PIA09011.jpgThe "Crowded" Saturnian Sky54 visiteCaption NASA:"A string of icy moons stretches across the Saturn System in this view from nearly edge-on with the Ring-Plane.
Nearest to the Cassini spacecraft is Rhea (1528 Km, or about 949 miles across) below center; then little Atlas (32 Km, or about 20 miles across), huddled close to the narrow F-Ring. Dione (1126 Km, or about 700 miles across) floats in the distance beyond.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on July 8, 2007 at a distance of approx. 2,9 MKM (about 1,8 MMs) from Saturn. Image scale is roughly 14 Km (about 9 miles) per pixel on Rhea and 19 Km (about 12 miles) per pixel on Dione".MareKromium
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Rhea_and_Telesto-N00152419-22-EB.jpgRhea and Telesto (an Image-Mosaic by Elisabetta Bonora - Lunexit Team)55 visitenessun commentoMareKromium
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Rhea_and_Titan-EB.jpgJewels, in the Space of Saturn: Rhea and Titan (Natural Colors; credits: Elisabetta Bonora)57 visiteUn lavoro assolutamente PERFETTO e, detto sinceramente, di qualità mediamente superiore ai Lavori di colorizzazione "Made by NASA".
Complimenti vivissimi alla nostra Amica e Partner, Elisabetta Bonora!MareKromium
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Rhea_and_Titan-MF.jpgRhea and Titan (NIR View; credits: Dr M. Faccin)57 visite...Una "Visione" davvero splendida, da lasciare con il fiato sospeso...MareKromium
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Rhea~0.jpgRhea (false colors)66 visiteCaption NASA originale:"This false-color picture of Saturn's moon Rhea from Cassini enhances slight differences in natural color across the moon's face. The extreme north and south latitudes have a notable difference in hue compared to the mid-latitudes.
This view of Rhea is a composite of images taken using filters sensitive to green (centered at 568 nnmts) and infrared light (2 infrared filters, centered at 752 and 930 nnmts) and has been processed to accentuate subtle color differences.
The image was taken with the Cassini spacecraft narrow angle-camera on Feb. 18, 2005, at a distance of approximately 890.000 Km from Rhea and at a Sun-Rhea-spacecraft phase angle of 116°. The image scale is 5 Km per pixel".
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Rhea~1.jpgRhea55 visiteThe icy, cratered surface of Saturn's moon Rhea is seen in this HR image taken by Voyager 1 on November 11, 1980, from a distance of about 85.000 Km (such as approx. 52.800 miles) as the spacecraft passed over the Satellite's North Pole. The heavily cratered surface attests to the Satellite's ancient age. The largest craters, 50 to 100 Km across and several Km deep, are freshly preserved in Rhea's icy crust. The craters and landscape resemble those on the Moon and Mercury and are unlike the flattened crater forms that have collapsed in the soft icy crusts of the Jovian moons Callisto, Ganymede and Europa.
Scientists believe that Rhea (which is just 1600 Km - about 995 miles - in diameter, compared to the 5.500 Km of diameter of Ganymede) froze and became rigid, behaving like a rocky surface, very early in its history.
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Rings and Moons-PIA06501_modest.jpgRings and Moons (detail - x4 mgnf)56 visiteCaption NASA originale:"This image captures several important targets of the Cassini mission: icy moons, rings and the gaps in the rings that may contain small undiscovered moons. Mimas (398 Km across) is easily seen near lower right. Epimetheus (116 Km across) is visible left of center. The 4.800 Km wide Cassini division is the dark swath at upper left. The Encke Gap (325 Km wide) is visible as a dark curve near the edge of the A-Ring. The thin F-Ring is seen here, exterior to the main rings.
The image was taken in visible light with the Cassini spacecraft narrow angle camera on Sept. 10, 2004, at a distance of 8.9 MKm(5.5 million miles) from Mimas and at a Sun-Mimas-spacecraft (or "phase") angle of 84°. The image scale is 53 Km per pixel.
The image was magnified by a factor of four to aid visibility".
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Rings-PIA03556.jpg"Clumps" in the A-Ring58 visiteOriginal NASA caption:"The left image is a false-color view of Saturn's A-Ring from the Ultraviolet Imaging Spectrograph aboard Cassini.
The A-Ring is the bluest in the center, where the gravitational clumps are the largest. The thickest black band in the Ring is the "Encke-Gap" while the thin black band further to the right is the "Keeler-Gap".
The right image is a computer simulation about 150 mt (about 490 feet) across illustrating a "clumpy region" of particles in the A-Ring. And, there and that is the 'real surprise'...The particles are moving counterclockwise, from bottom to top!".
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