Saturn: the "Ringed Beauty" and His Moons
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Hyperion-PIA06486.jpgHyperion, the "tumbling" moon53 visiteUn'immagine non particolarmente bella ma comunque densa di suggestione e di mistero: si tratta di Iperione (o "Hyperion"), la luna di Saturno che non "scorre", ma "rotola" (come dicono gli Scienziati) lungo la sua orbita. Si tratta, probabilmente, di una delle lune che sono state - letteralmente - "rubate" dal Signore degli Anelli: un macigno proveniente dalle profondità del Sistema Solare (un "KBO") che si è avvicinato troppo a Saturno ed è stato catturato dal suo "abbraccio gravitazionale". Il movimento caotico di Iperione - tenendo a mente che l'impulso iniziale impresso ad un corpo, nello spazio, viene dal corpo stesso mantenuto (praticamente) all'infinito - deriva, con ogni probabilità, dal fatto che si tratta di un frammento di un oggetto celeste di più grandi dimensioni il quale andò in pezzi a seguito di un impatto occorso in epoche assai remote.
Una delle "schegge" che derivarono dalla collisione la vediamo orbitare (anzi: "rotolare") ancora oggi intorno a Saturno: questo è Iperione.
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Hyperion-PIA06527.jpgHyperion from approx. 2.200.000 Km53 visiteCaption NASA originale:"This image reveals the odd shape of Saturn's moon Hyperion and an intriguing variation in brightness across its surface (ndr: just like Japetus?!?).
The diameter of Hyperion is 266 Km.
The image was taken in visible light with the Cassini spacecraft narrow angle camera on Oct. 20, 2004, at a distance of about 2.2 MKM from Hyperion and at a Sun-Hyperion-spacecraft, or phase, angle of 50°. The image scale is 13 Km per pixel".
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Hyperion-PIA06608[1].jpgThumbling Hyperion96 visiteCaption NASA originale:"As it loops around Saturn, Cassini periodically gets a good view of Saturn's moon Hyperion. Hyperion chaotically tumbles around in its orbit and is perhaps the largest irregularly-shaped moon in the Solar System. New details about this oddball worldlet will certainly come to light in September, 2005, when Cassini is slated to approach Hyperion at a distance of 990 Km. The images were taken in visible light with the Cassini spacecraft narrow-angle camera in October 2004 and February 2005, at distances ranging from 1,3 to 1,6 MKM (such as from approx. 808.000 to 994.000 MMs) from Hyperion and at phase angles ranging from 42 to 66°. Resolution in the original images was 8 to 10 Km (approx. 5 to 6 miles) per pixel.
The images have been contrast-enhanced and magnified by a factor of two to aid visibility".
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Hyperion-PIA06623.jpgHyperion from 1,7 MKM53 visiteCaption NASA originale:"The rugged surface of Saturn's irregular (and "tumbling") moon Hyperion is revealed in this Cassini image. Hyperion is 266 Km (approx. 165 miles) across.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Feb. 23, 2005, at a distance of approx. 1,7 MKM (such as approx. 1 MMs) from Hyperion and at a Sun-Hyperion-spacecraft, or phase, angle of 42°. Resolution in the original image was 10 Km (approx. 6 miles) per pixel. The image has been contrast-enhanced and magnified by a factor of 3 to aid visibility".
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Hyperion-PIA06643.jpgSome of Hyperion's main surface features54 visiteCaption NASA originale:"Several distinct craters on Saturn's moon Hyperion can be seen here, as well as a protruding feature, perhaps a mountain, near the center.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on March 16, 2005, at a distance of approx. 1,8 MKM (such as approx. 1,1 MMs) from Hyperion and at a Sun-Hyperion-spacecraft, or phase, angle of 42°.
Resolution in the original image was 11 Km (approx. 7 miles) per pixel. The image has been contrast-enhanced and magnified by a factor of three to aid visibility".
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Hyperion-PIA06645.jpgThe "tumbling" Hyperion is still on sight53 visitenessun commento
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Hyperion-PIA07739.jpgGood-bye Hyperion...53 visiteOriginal caption:"As Cassini sped away from its close encounter with Saturn's moon Hyperion on Sept. 26, 2005, it took this parting shot of the battered moon's shadowy limb.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera at a distance of approx. 32.300 Km (about 20.000 miles) from Hyperion and at a Sun-Hyperion-spacecraft angle of 127°.
Image scale is 192 meters (630 feet) per pixel".
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Hyperion-PIA07740-PCF-LXTT-IPF.jpgFeatures of Hyperion (CTX and EDM Frames in Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)109 visiteThese beautiful Absolute Natural Color views of the Saturnian moon Hyperion reveal crisp details across the strange, tumbling moon's Surface. Differences in color represent differences in the composition of the Surface Materials; both views (CTX Frame and EDM) were obtained during the Cassini's close Fly-By that occurred on September, 26, 2005.
The images were taken by the NASA - Cassini Spacecraft's narrow-angle camera at a distance of approx. 62.000 Km (about 38.500 miles) from Hyperion and at a Sun-Hyperion-Cassini Angle (a.k.a. "Phase Angle") of 52°. The image scale is 362 mt (about 1200 feet) per pixel.
These two frames have been colorized in Absolute Natural Colors (such as the colors that a human eye would actually perceive if someone were onboard the NASA - Cassini Spacecraft and then looked outside, towards the Saturnian moon Hyperion), by using an original technique created - and, in time, dramatically emproved - by the Lunar Explorer Italia Team.MareKromium
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Hyperion-PIA07740.jpgHyperion - false colors56 visiteOriginal caption:"This stunning false-color view of Hyperion reveals crisp details across the strange, tumbling moon's surface. Differences in color could represent differences in the composition of surface materials. The view was obtained during Cassini's close flyby on Sept. 26, 2005.
Hyperion has a notably reddish tint when viewed in natural color. The red color was toned down in this false-color view and the other hues were enhanced, in order to make more subtle color variations across Hyperion's surface more apparent.
Images taken using infrared, green and ultraviolet spectral filters were combined to create this view. The images were taken with the Cassini spacecraft's narrow-angle camera at a distance of approx. 62.000 Km (about 38.500 miles) from Hyperion and at a Sun-Hyperion-spacecraft angle of 52°.
The image scale is 362 mt (about 1200 feet) per pixel".
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Hyperion-PIA07741-1.jpgHyperion's unusual craters (1) - HR53 visiteOriginal caption:"This HR Cassini mosaic shows that Hyperion truly has a surface different from any other in the Saturn System. The mosaic is composed of 5 clear filter images taken during Cassini's close flyby of Hyperion on Sept. 26, 2005. The spacecraft passed approximately 500 Km(310 miles) above the moon's surface. Hyperion is 266 Km (about 165 miles) in diameter.
Scientists are extremely curious to learn what the dark material is that fills many craters on this oddball moon. Features within the dark terrain, including a 200-meter-wide impact crater surrounded by rays to the right of center (Sezione 3 del frame) and numerous bright-rimmed craters, indicate that the dark material may be only tens of meters (hundreds of feet) thick with brighter material beneath".
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Hyperion-PIA07741-2.jpgHyperion's unusual craters (2) - HR59 visiteOriginal caption:"Scientists will also be examining Cassini's sharp views to try to determine whether there have been multiple episodes of landslides on Hyperion. Such "downslope" movement is evident in the filling of craters with debris and the near elimination of many craters along the steeper slopes. Answers to these questions may help solve the mystery of why this object has evolved different surface forms from other moons of Saturn.
The images comprising this mosaic were taken with the Cassini spacecraft narrow-angle camera at distances ranging from approximately 8.500 Km (about 5.300 miles) to 4.600 Km (about 2.900 miles) from Hyperion. Image scale is 26 mt (about 85 feet) per pixel".
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Hyperion-PIA07741-3.jpgHyperion's unusual craters (3) - HR53 visiteUn piccolo applauso a Lunar Explorer Italia la quale, con due giorni e mezzo di anticipo sulla NASA (Commenti Ufficiali), è riuscita ad individuare ed estrapolare, dall'analisi dei "raw frames Cassini" - usando gli occhi dei Ricercatori e qualche altro mezzo informatico davvero "povero"... - le tematiche di maggiore interesse che riguardano questa piccola Luna Saturniana e che la NASA stessa ha, come avete letto nelle note di commento - "original caption" - ai due frames precedenti, enfaticamente portato all'attenzione dei Lettori.
Un "Bravo" a Lunar Explorer Italia quindi (...che ogni tanto lo meritiamo davvero...).
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