Saturn: the "Ringed Beauty" and His Moons
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Atlas-PIA09907.jpgBrothers in the Night: Atlas and Daphnis54 visiteCaption NASA:"Looking upward from beneath the Ring-Plane, the Cassini Spacecraft spies Saturn's "Wave Maker" and "Flying Saucer" moons.
Daphnis (8 Km, or about 5 miles across at its widest point) and its gravitationally induced edge waves are seen at left within the Keeler Gap. The equatorial bulge on Atlas (30 Km, or about 19 miles across at its widest point) is clearly visible here.
This view looks toward the sunlit side of the Rings from about 16° below the Ring-Plane. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on April 22, 2008. The view was acquired at a distance of approx. 898.000 Km (such as about 558.000 miles) from Saturn.
Image scale is roughly 5 Km (about 3 miles) per pixel".MareKromium
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Atlas-PIA11494.jpgAtlas and a few Stars56 visiteCaption NASA:"Atlas is seen in this image with several background stars as the moon orbits within the Roche Division — the Region between Saturn's A and F-Rings.
Atlas (about 30 Km, or approx. 19 miles across) is in the top left quadrant of the image.
This view looks toward the sunlit side of the Rings from about 65° below the Ring-Plane. The image was taken in Visible Light with the Cassini Spacecraft narrow-angle camera on March 23, 2009. The view was acquired at a distance of approx. 913.000 Km (about 567.000 miles) from Saturn and at a Sun-Saturn-Spacecraft, or Phase, Angle of 105°.
Image scale is roughly 5 Km (a little more than 3 miles) per pixel".MareKromium
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Atlas.jpgAtlas (Credits: Dr Marco Faccin and Elisabetta Bonora)183 visitenessun commentoMareKromium
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Atlas_Pan-PIA08405.jpgJust like Flying Saucers: Atlas and Pan56 visiteCaption NASA:"These HR images of Pan and Atlas reveal distinctive "flying saucer" shapes created by prominent Equatorial Ridges not seen on the other small moons of Saturn.
From left to right: a view of Atlas' Trailing Hemisphere, with North up, at a spatial scale of about 1 Km (0,6 mile) per pixel; Atlas seen at about 250 meters (820 feet) per pixel from Mid-Southern Latitudes, with the Sub-Saturn Hemisphere at the top and Leading Hemisphere to the left; Pan's Trailing Hemisphere seen at about 3 Km (about 2 miles) per pixel from low Southern Latitudes; an Equatorial view, with Saturn in the background, of Pan's Anti-Saturn Hemisphere at about 1 Km (0.6 mile) per pixel.
On Atlas, the ridge extends 20 to 30° in latitude on either side of the Equator; on Pan, its latitudinal extent is 15 to 20°. Atlas shows more asymmetry than Pan in having a more rounded ridge in the Leading and Sub-Saturn Quadrants.
The heights of the Ridges can be crudely estimated by assuming (ellipsoidal) shapes that lack ridges and vary smoothly cross the Equator. Heights of Atlas' Ridge range from about 3 Km (about 2 miles) at 270° West Long. to 5 Km (approx. 3 miles) at 180 and 0°. Pan's Ridge reaches about 4 Km (about 2,5 miles) at 0° West Long. and is about 1,5 Km (0,9 mile) high over most of the rest of the Equator.
The ridges represent about 27% of Atlas' volume and 10% of Pan's volume.
The images were acquired with the Cassini Spacecraft narrow-angle camera between 2005 and 2007. Pan is about 33 Km (apprx. 20,5 miles) across at its Equator and about 21 Km (approx. 13 miles) across at its Poles; Atlas is 39 Km (such as about 24 miles) across at its Equator and 18 Km (approx. 11 miles) across at its Poles".MareKromium
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Atlas_Pan-PIA08946.jpgBrothers in the Night: Atlas & Pan54 visiteCaption NASA:"Atlas and Pan emerge from the Far Side of Saturn.
Light passing through the upper reaches of the Planet's Atmosphere is refracted, or bent, distorting the image of the Rings beyond.
Pan (about 26 Km, or 16 miles across) is seen within the Encke Gap. Atlas (about 32 Km, or 20 miles across) orbits just beyond the outer edge of Saturn's A-Ring.
This view looks toward the unilluminated side of the Rings from about 12° above the Ring-Plane. Shadows cast by the Rings arc across the Planet toward the Cassini spacecraft.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on April 12, 2007 at a distance of approx. 1,6 MKM (about 1 MMs) from Saturn.
Image scale is roughly 10 Km (a little more than 6 miles) per pixel".MareKromium
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Aurora Borealis on Saturn (HST).jpgAurora Borealis on Saturn (HST)113 visiteUn'Aurora Boreale sul Polo Sud di Saturno: forse la cosa non sorprenderà nessuno e l'immagine che Vi proponiamo, infatti, è piuttosto vecchia (siamo nel Gennaio 1998).
Siamo tuttavia certi che solo pochi Appassionati e Ricercatori sanno che, solo sino a pochissimi anni fa, la Comunità Scientifica Mondiale supponeva che le Aurore Boreali (che Hubble ha fotografato mentre si scatenavano su tutti i Giganti Gassosi) fossero un fenomeno 'tipicamente terrestre'.
E così chissà quante altre fenomenologie che riteniamo essere 'tipicamente terrestri' sono, in realtà, una prerogativa comune all'intero Universo...
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Calypso-EB1.jpgCalypso (Natural Colors; credits: Elisabetta Bonora)54 visitenessun commentoMareKromium
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Calypso-EB2.jpgCalypso (Natural Colors; credits: Elisabetta Bonora)116 visite...Altro "Frammento Artistico" che ci rammenta le sfumature e le tenui - ma sempre affascinanti - colorazioni di Mondi immersi nel solo "Chiaro di Stelle" e, probabilmente, ancora troppo lontani dall'Immaginario Collettivo per suscitare interessi particolari. Purtroppo.
Grandi Complimenti ad Elisabetta Bonora per il Lavoro!MareKromium
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Calypso-MF.gifFloating in Space... (GIF-Movie; credits: Dr M. Faccin - Lunexit Team)55 visitenessun commentoMareKromium
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Calypso-N00040025.jpgCalypso in the darkness55 visitePerduta nell'oscurità incombente dello Spazio, così come una minuscola isola - dimenticata dalle mappe dei Naviganti - è persa nell'Oceano: questa è Calypso, una piccola luna di Saturno la quale, se la osservate con attenzione, denuncia la sua natura di "scheggia vagante", catturata dalle braccia gravitazionali di Saturno e sottratta, in epoche (presumiamo) assai remote, al suo peregrinare senza mèta nei recessi del Sistema Solare.
Valutazioni romantiche a parte, in questo bellissimo frame, Calypso è a poco più di 100.000 Km di distanza da Cassini, ma qualche suo rilievo superficiale - oltre alla forma, decisamene peculiare... - si può già intuire: un grande bacino (da impatto?) marca il Polo Sud di Calypso, mentre un altro cratere, più vasto e meno profondo, sembra segnare il Polo Nord di questo piccolo mondo la cui forma - attenzione! - ricorda in maniera davvero impressionante quella dell'asteroide 433 Eros.
Identità di natura, coincidenza o un segnale di ripetitività?
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Calypso-PIA07633.jpgCalypso (in false colors)54 visiteThis color image provides the best look yet at Saturn's moon Calypso, a Trojan of the larger moon Tethys. Calypso trails Tethys in its orbit by 60°. Telesto is the other Tethys Trojan, orbiting Saturn 60°ahead of Tethys. Calypso is only 22 Km (about 14 miles) across. Calypso, like many other small Saturnian moons and small asteroids, is irregularly shaped by overlapping large craters. Although the resolution here is not as high as in Cassini's best images of Pandora and Telesto, this moon appears to also have loose surface material capable of smoothing the appearance of craters. (...) The images were taken with the Cassini spacecraft narrow-angle camera on Sept. 23, 2005, at a distance of approx. 101.000 Km (about 63.000 mi) from Calypso and at a phase angle of 61°. Resolution in the original image was 602 mt per pixel (...) ".
Nota: notiamo un'incredibile somiglianza fra Calypso e l'asteroide 433-Eros. Coincidenza, o c'è una sorta di "marchio di fabbrica" che unisce le piccole lune agli asteroidi?
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Cosmic_WaterFall-N00160095-N00160115_logo.gifCosmic Waterfall (a GIF-Movie by Dr Gianluigi Barca - Lunexit Team)58 visitenessun commentoMareKromium
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