| Ultimi arrivi - Original NASA Frames - Jupiter and the "Jupiter System" through Voyager 1 and 2 |
507-PIA01517.jpgThe equatorial Region of Ganymede55 visiteCaption NASA originale:"This picture is relevant to a Regione near the Equator of Ganymede, and has relatively subdued colors in the visible part of the spectrum. The most striking features are the bright ray craters which have a distinctly bluer color, appearing white against the redder background.
Ganymede's surface is known to contain large amounts of surface ice and it appears that these relatively young craters have spread bright fresh ice materials over the surface.
Likewise, the lighter color and reflectivity of the grooved areas suggest that here, too, there is cleaner ice. We see ray craters with all sizes of ray patterns, ranging from extensive systems, down to craters which have only faint remnants of bright ejecta patterns.
This variation suggests that, as on the Moon, there are processes which act to darken ray material - probably the so-called "gardening", by micrometeoroid impacts".Set 16, 2006
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505-PIA00356.jpgGanymede (Enhanced Natural Colors and HR; credits: NASA/JPL)55 visiteCaption NASA originale:"This color reconstruction of part of the Northern Hemisphere of Ganymede was made from pictures taken from a range of about 313.000 Km (approx. 194.000 miles).
The scene is approx. 1.300 Km (about 806 miles) across and it shows part of dark, densely cratered block which is bound on the south by lighter and less cratered, grooved terrain.
The dark blocks are believed to be the oldest parts of Ganymede's surface. Numerous craters are visible, many with central peaks. The large bright circular features have little relief and are probably the remnants of old, large craters that have been annealed by flow of the icy near-surface material.
The closely-spaced arcuate, linear features are probably analogous to similar features on Ganymede which surround a large impact basin.
The linear features here may indicate the former presence of a large impact basin to the South-West".Set 16, 2006
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505-PIA00357.jpgGanymede (Enhanced Natural Colors and HR; credits: NASA/JPL)54 visiteCaption NASA originale:"This color picture of Ganymede is relevant to a Region located at 30° South Lat. and 180° West Long. It shows features as small as 6 Km (about 3,7 miles) across. Notice here a bright halo impact crater that shows the fresh material thrown out of the crater. In the background it can be seen a bright grooved terrain that may be the result of the shearing of the surface materials along fault planes.
The dark background material is the ancient heavily cratered terrain -- probably the oldest material preserved on the surface of Ganymede".Set 16, 2006
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504-PIA01516.jpgGanymede (natural colors and HR)54 visiteCaption NASA originale:"This color picture as acquired by Voyager 1 during its approach to Ganymede, at ranges between about 230 to 250.000 Km. The image shows detail on the surface with a resolution of 4,5 Km/px.
This picture shows the two distinctive types of terrain found by Voyager: the darker ungrooved regions and the lighter areas which show the grooves or fractures in abundance. The most striking features are the bright ray craters which have a distinctly "bluer" color appearing white against the redder background. Ganymede's surface is known to contain large amounts of surface ice and it appears that these relatively young craters have spread bright fresh ice materials over the surface. Likewise, the lighter color and reflectivity of the grooved areas suggests that here too, there is cleaner ice. We see ray craters with all sizes of ray patterns, ranging from extensive systems of the crater in the northern part of this picture, which has rays at least 300-500 kilometers long, down to craters which have only faint remnants of bright ejecta patterns".Set 16, 2006
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502-PIA01515.jpgGanymede (natural colors and HR)62 visiteCaption NASA originale:"This color picture was acquired by Voyager 1 during its approach to Ganymede. At ranges between about 230 to 250.000 Km. The images show detail on the surface with a resolution of 4,5 Km/px. This picture is relevant to a region in the Northern Hemisphere, near the terminator. It shows a variety of impact structures, including both razed and unrazed craters, and the odd, groove-like structures discovered by Voyager in the lighter regions. The most striking features are the bright ray craters which have a distinctly 'bluer' color appearing white against the redder background. Ganymede's surface is known to contain large amounts of surface ice and it appears that these relatively young craters have spread bright fresh ice materials over the surface. Likewise, the lighter color and reflectivity of the grooved areas suggests that here, too, there is cleaner ice".Set 16, 2006
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501-vg1_1641854.jpgGanymede (HR)54 visitenessun commentoSet 16, 2006
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500-PIA02233.jpgGanymede (HR)54 visiteCaption NASA originale:"This picture of Ganymede was taken from a range of about 272.000 Km. The center of the picture lies at 13° Latitude and 359° Longitude. Many bright impact craters are shown that have radial ejecta patterns. These rays lie across and therefore are younger than the bright and dark background material. Many older impact craters are shown that have lost their rays probably by impact erosion. The bright background areas contain grooves and ridges that may be caused by faulting of the surface materials".Set 16, 2006
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49-vg1_visualcmp.jpgThe "Object" near Io and the one near Callistus: visual comparison (extreme detail mgnf)72 visiteNon servono ulteriori commenti...Set 09, 2006
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45-vg1_1639948.jpgCallistus: the "dark moon" and another (?) "strange companion" (b/w)57 visiteCome segnalatoci dal nostro Ricercatore Esterno, Dr G. Barca, anche nelle prossimità di Callisto sembra esserci uno "strano compagno". Che sia lo stesso oggetto che avevamo incontrato nei pressi di "Io"?
Le porte della Fantasia sono aperte: allora, escludendo (con riserva e sino a prova contraria) l'ipotesi per cui il "puntino bianco" sia un image-artifact, che cosa potrà mai essere? Un'altra "luna provvisoria", questa volta di Callisto? Un altro "corpo vagante" - magari una "futura cometa"?
O forse si tratta di un qualcosa di Alieno che sta osservando (e seguendo?) la Sonda Voyager 1?
Come sempre, noi Vi diamo tutti gli elementi disponibili: al resto provate a rispondere Voi stessi...Set 09, 2006
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44-vg1_1637750.jpgThe "Strange Companion" of Io (extreme detail mgnf)54 visiteL'oggetto a noi pare lo stesso (a tutti gli effetti) del frame VG1-1636836: il super-stretching ne evidenzia alcune, minime, caratteristiche superficiali e la sua dimensione apparente, a parità di stretching, suggerisce che esso si stia allontanando dalla Sonda Voyager.
Incredibile, vero?!?
Un vero peccato che, anche in questo caso, la NASA non abbia MAI speso una parola (se non altro per dire, ad esempio, "è solo un image artifact"...).
Mai.Set 09, 2006
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43-vg1_1637750.jpgIo: the "restless moon" and a "strange companion" (b/w)61 visiteIndubitabile: qualsiasi cosa esso sia, l'oggetto (il "Transient", come abbiamo deciso di identificare questi corpi erranti e dalla natura imprecisata) si è mosso, e per giunta MOLTO rapidamente...Set 09, 2006
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43-vg1_1636836.jpgThe "Strange Companion" of Io (extreme detail mgnf)57 visiteForma irregolare, ma rotondeggiante; albedo elevata; nessun segno di rilievi superficiali.
Allora: una piccola "luna di Io", un "corpo vagante", una "cometa in divenire" oppure...una Alien Probe.
Decidete Voi.Set 08, 2006
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