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Jupiter: the "King" and His Moons
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Europa-PIA01970.jpgApproaching Europa53 visiteCaption NASA originale:"View of Europa taken from a range of 2.869.252 Km (such as about 1,6 MMs). The color composite is made from three black and white images taken through the orange, green and violet filters. The 170° Longitude is at the center of the picture; this is the face away from Jupiter. Irregular dark and bright patches on the surface are different from the patterns on the other satellites of Jupiter and those on the Moon, Mars and Mercury. Dark intersecting lines may be faults that break the crust".
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Europa-PIA02500.jpgFrozen H2SO4 (Sulphuric Acid) on Europa?52 visiteFrozen Sulfuric Acid on Jupiter's moon Europa is depicted in this image produced from data gathered by NASA's Galileo spacecraft. The brightest areas, where the yellow is most intense, represent Regions of high frozen Sulfuric Acid concentration. Sulfuric Acid is found in "exhaust battery acid" and in Earth's acid rain.
This image is based on data gathered by Galileo's NIMS (Near Infrared Mapping Spectrometer).
Europa's Leading Hemisphere is toward the bottom right and there are enhanced concentrations of Sulfuric Acid in the Trailing Side of Europa (the upper left side of the image). This is the face of Europa that is struck by sulfur ions coming from Jupiter's innermost moon, Io. The long, narrow features that criss-cross Europa also show Sulfuric Acid that may be from sulfurous material extruded in cracks.
Galileo, launched in 1989, has been orbiting Jupiter and its moons since December 1995.
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Europa-PIA03002_modest.jpgGeologic evidence of a "liquid" Ocean under Europa's icy surface52 visiteCaption NASA originale:"The image on the left shows a region of Europa's crust made up of blocks which are thought to have broken apart and rafted into new positions. These features are the best geologic evidence to date that Europa may have had a subsurface ocean at some time in its past. Combined with the geologic data, the presence of a magnetic field leads scientists to believe an ocean is most likely present at Europa today. In this false color image, reddish-brown areas represent non-ice material resulting from geologic activity. White areas are rays of material ejected during the formation of the 25-Km diameter impact crater Pwyll (see global view). Icy plains are shown in blue tones to distinguish possibly coarse-grained ice (dark blue) from fine-grained ice (light blue). Long, dark lines are ridges and fractures in the crust, some of which are more than 3.000 Km long. These images were obtained by NASA's Galileo spacecraft during September and December 1996 and February 1997".
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Europa-PIA03878_modest.jpgLenticulae on Europa64 visiteCaption NASA originale:"Reddish spots and shallow pits pepper the enigmatic ridged surface of Europa in this view combining information from images taken by the Galileo spacecraft during 2 orbits. The spots and pits visible in this region of Europa's northern hemisphere are each about 10 Km across. The dark spots are called "lenticulae," the Latin term for freckles. Their similar sizes and spacing suggest that Europa's icy shell may be churning away like a lava lamp, with warmer ice moving upward from the bottom of the ice shell while colder ice near the surface sinks downward. Other evidence has shown that Europa likely has a deep melted ocean under its icy shell. Ruddy ice erupting onto the surface to form the lenticulae may hold clues to the composition of the ocean and to whether it could support life".
Nota Lunexit: Si, la NASA parla di un "profondo oceano liquido" al di sotto della crosta ghiacciata di Europa.
Un oceano "vivo", forse?
Ci chiediamo: ma perchè abbiamo abbandonato questa strada (sempre complessa, ma più vicina e più solida) per andare a cercare "qualcosa" di completamente indefinibile - e per giunta muovendoci alla cieca - su Titano?
Insomma, l'idea del Landing su Titano (attuata) è stata un Grande Passo, ma fermarsi su Europa e guardare meglio era proprio un'idea sbagliata?!?... Misteri della NASA.
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Europa-PIA10131.jpgThe Inner Ocean of Europa53 visiteCaption NASA:"Scientists are all but certain that Europa has an ocean underneath its icy surface, but they do not know how thick this ice might be. This artist concept illustrates 2 possible cut-away views through Europa's ice shell. In both, heat escapes, possibly volcanically, from Europa's rocky mantle and is carried upward by buoyant oceanic currents. If the heat from below is intense and the ice shell is thin enough (left), the ice shell can directly melt, causing what are called "chaos" on Europa, regions of what appear to be broken, rotated and tilted ice blocks. On the other hand, if the ice shell is sufficiently thick (right), the less intense interior heat will be transferred to the warmer ice at the bottom of the shell, and additional heat is generated by tidal squeezing of the warmer ice. This warmer ice will slowly rise, flowing as glaciers do on Earth, and the slow but steady motion may also disrupt the extremely cold, brittle ice at the surface.
Europa is no larger than Earth's moon, and its internal heating stems from its eccentric orbit about Jupiter, seen in the distance. As tides raised by Jupiter in Europa's ocean rise and fall, they may cause cracking, additional heating and even venting of water vapor into the airless sky above Europa's icy surface".MareKromium
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Europa-PIA10149.jpgThe Inner Ocean of Europa53 visiteCaption NASA:"Like Earth, Europa is thought to have an iron core, a rocky mantle and a surface ocean of salty water. Unlike on Earth, however, this ocean is deep enough to cover the whole moon, and being far from the Sun, the ocean surface is globally frozen over.
Europa's orbit is eccentric, which means as it travels around Jupiter, large tides, raised by Jupiter, rise and fall. Jupiter's position relative to Europa is also seen to librate, or wobble, with the same period. This tidal kneading causes frictional heating within Europa, much in the same way a paper clip bent back and forth can get hot to the touch, as illustrated by the red glow in the interior of Europa's rocky mantle and in the lower, warmer part of its ice shell. This tidal heating is what keeps Europa's ocean liquid and could prove critical to the survival of simple organisms within the ocean, if they exist".MareKromium
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Europa-PIA23166.jpgRhadamanthys Linea (Enhanced Natural Color Version)134 visiteCaption NASA Originale:"Europa's Surface is covered with a vast network of Linear Features such as cracks, ridges, and bands, as well as other smaller circular features that include pits, spots, domes, and microchaos.
This image, created from clear-filter images taken on the Galileo spacecraft's 17th orbit around Jupiter and colorized with lower-resolution images taken on Galileo's first orbit around Jupiter, shows a huge variety of these feature types.
Of particular note is the prominent ridge at the center of the image, called Rhadamanthys Linea.
While most ridges have a reddish appearance in colorized images such as this enhanced color version, Rhadamanthys appears to have uneven blotches of darker, redder material which are more prominent in some locations than in others.
Some scientists have interpreted the appearance of Rhadamanthys to indicate that it is a recently, or perhaps currently, active feature on Europa's Surface".MareKromium
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Europa-Ridges-PIA00518-PCF-LXTT.jpgRidges on Europa (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)156 visitenessun commentoMareKromium
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Europa-Ridges-PIA00518.jpgRidges on Europa53 visiteThis view of Jupiter's moon Europa shows a portion of the surface that has been highly disrupted by fractures and ridges. This picture covers an area about 238 Km (approx. 150 miles) wide by 225 Km (about 140 miles); in other words, the distance between Los Angeles and San Diego. Symmetric ridges in the dark bands suggest that the surface crust was separated and filled with darker material, somewhat analogous to spreading centers in the ocean basins of Earth. Although some impact craters are visible, their general absence indicates a youthful surface. The youngest ridges, such as the two features that cross the center of the picture, have central fractures, aligned knobs, and irregular dark patches. These and other features could indicate cryovolcanism, or processes related to eruption of ice and gases.
This picture, centered at 16° South Lat. and 196° West Long., was taken at a distance of 40.973 Km (about 25.290 mi) on November 6, 1996, by the Galileo spacecraft Solid State Imaging Television Camera.
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Europa-Ridges-PIA17737-PCF-LXTT-IPF-1.jpgFeatures of Europa (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga/Lunar Explorer Italia/Italian Planetary Foundation)89 visiteThis image, taken by the NASA - Galileo Spacecraft on February, 2, 1999, shows us huge Cracks and Ridges on the Surface of the Jovian moon Europa. These (absolutely fascinating) Features reveal a complex Geologic History of Europa. Some Ridges, such as the prominent one, at the top right of the frame, develop into several long, arc-shaped "Cycloids" (---> a Cycloid is the curve traced by a point on the rim of a circular wheel as the wheel rolls along a straight line), that could reasonably be related to the changing Tidal Forces as Europa orbits the Gas-Giant Planet Jupiter. The Wall of this Ridge stands perhaps a third of a mile (approx. 0,5 Km) above the surrounding Ridged Plains, although their Edges are - likely - NOT as steep as they appear in this view.
The view was captured by the NASA - Galileo Spacecraft on February 2, 1999, during its E19 orbit, when the spacecraft was about 2500 miles (such as approx. 4023 km) from the Surface of Europa. The Resolution in the scene is roughly 295 feet (such as approx. 89.91 meters) per pixel. North is toward bottom left side of the picture.
This frame (which is a crop taken from an Original NASA - Galileo Spacecraft enhanced color image published on the NASA - Planetary Photojournal with the ID n. PIA 17737) has been additionally processed, contrast enhanced, magnified to aid visibility of the Surface details and then re-colorized, according to an educated guess carried out by Dr Paolo C. Fienga/LXTT/IPF, in what they should be its Absolute Natural Colors (such as the colors that a human eye would actually perceive if someone were onboard the NASA - Galileo Spacecraft and then looked outside, towards the Surface of the Jovian moon Europa), by using an original technique created - and, in time, dramatically improved - by the Lunar Explorer Italia Team. Different colors, as well as different shades of the same color, mean, among others, the existence of different Elements present on the Surface of Europa, each having a different Albedo (---> Reflectivity) and Chemical Composition.
Note: it is possible (but we, as IPF, have no way to be one-hundred-percent sure of such a circumstance), that the actual luminosity of Europa- as it is in this frame - would appear, to an average human eye, a little bit lower than it has been shown (or, better yet: interpreted) here.MareKromium
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Europa-Thera and Thrace Macula-PIA00875.jpg"Thera" and "Thrace" Macula on Europa53 visiteThis image of Europa's southern hemisphere was obtained by the solid state imaging (CCD) system on board NASA's Galileo spacecraft during its sixth orbit of Jupiter. The upper left portion of the image shows the southern extent of the "wedges" region, an area that has undergone extensive disruption. South of the wedges, the eastern extent of Agenor Linea (nearly 1000 kilometers in length) is also visible. Thera and Thrace Macula are the dark irregular features southeast of Agenor Linea. This image can be used by scientists to build a global map of Europa by tying such Galileo images together with images from 1979 during NASA's Voyager mission. Such lower resolution images also provide the context needed to interpret the higher resolution images taken by the Galileo during both its nominal mission and the upcoming Europa mission. North is to the top of the picture and the sun illuminates the surface from the right. The image, centered at -40 latitude and 180 longitude, covers an area approximately 675 by 675 kilometers. The finest details that can be discerned in this picture are about 3.3 kilometers across. The images were taken on Feb 20, 1997 at 12 hours, 55 minutes, 34 seconds Universal Time when the spacecraft was at a range of 81,707 kilometers.
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Europa-V1-PIA00016-0.jpgEuropa53 visite"TUTTI QUESTI MONDI VI APPARTENGONO, TRANNE EUROPA: NON TENTATE DI ATTERRARVI.
VIVETECI INSIEME.
VICETECI IN PACE".
Ricordate questa "famosissima" trasmissione (diretta alla Terra ed all'equipaggio dell'astronave Sovietica "Leonov") proveniente dall'astronave Americana "Discovery", in quel momento guidata dall'Elaboratore HAL 9000?
Naturalmente stiamo parlando di "2010 - Odissea 2", il prosieguo cinematografico dell'immortale capolavoro di Sir Stanley Kubrick "2001 - A Space Odyssey".
Europa: la culla di una Nuova Civiltà, da studiare "restando lontani", così da non contaminarla con la nostra arroganza e supponenza.
Due film da rivedere e, dopo aver visto queste immagini, su cui provare a meditare...
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