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| Risultati della ricerca nelle immagini - "Volcanic" |
0-APOLLO 15-launch_wide.jpgThe Launch of Apollo 15227 visiteThe "ORIGINAL" Apollo Time-Table (from Apollo 13)
APOLLO 13. March, 1970. Land in Fra Mauro formation of flat highlands, stay about 22 hours. Collect soil and rock from an old area relatively untouched by what many believed were ancient floods or volcanoes.
APOLLO 14. July, 1970. Land in Censorinus Crater area for a stay of about 22 hours. Investigate craters, possibly carved in Moon's surface by meteors.
APOLLO 15. November, 1970. Land in Littrow area of volcano-like projections, remain about 22 hours. Attempt a pinpoint landing on an exact, pre-selected target.
APOLLO 16. March, 1971. Descend to Crater Copernicus, remaining for about 70 hours. Extract from crater and high-rising column within formation rocks believed to be from far below the lunar surface.
APOLLO 17. Late in 1971. Land near rugged highland crater Tycho for stay of about 70 hours. Test first moon "rover" vehicle.
APOLLO 18. Early 1972. Land in Marius Hills, remain about 70 hours. Collect soil and rock samples from volcanic-like domes and valleys between.
APOLLO 19. Middle or late 1972. Land deep in Schroeter's Valley, with about 70 hours on the surface. Attempt a descent into a deep crater to determine cause of mysterious "red flashes" seen there by astronomers.
APOLLO 20. Late 1972 or early 1973. Land near the Hyginus Rill, a long, major canyon, for stay of about 70 hours. Investigate canyon for possible lunar core material.
This timeline had been altered slightly even before the Apollo 13 mission, when in January, 1970, Apollo 20 was cancelled in order to reserve the last production Saturn V for use in launching the planned Skylab orbiting laboratory a few years later. This change shifted the planned Apollo 18 and 19 lunar missions to 1974 to follow Skylab, but further budget-cutting in late 1970 also resulted in the cancellation of Apollo 18 and 19.
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00-Aristarchus Crater-2005-29-a-full_jpg.jpg01 - Aristarchus Crater (and Plateau)109 visiteThe HST Advanced Camera for Surveys snapped this close-up view of the Aristarchus crater on Aug. 21, 2005. The crater is 26 miles (about 42 Km) in diameter and approx. 2 miles (such as about 3,2 Km) in depth and sits at the South-Western edge of the Aristarchus Plateau. The Plateau is well known for its rich array of geologic features, including a dense concentration of volcanic rilles (such as river and valley-like landforms that resulted from the collapse of lava tubes) and source vents.
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019-The Moon from Clem-EastLimb-PIA00303.jpg005 - The eastern limb of the Moon: Mare Smythii, Mare Marginis, Mare Crisium and Mare Fecunditatis53 visiteThe dark albedo features Mare Smythii (image center) and Mare Marginis (above Smythii) are just visible from Earth on the extreme eastern edge of the Lunar Near-Side. Mare Crisium (West of Marginis) and Mare Fecunditatis (SouthWest of Crisium) are familiar Near-Side features as seen from Earth.
Maria Regions are believed to be large basins formed by impacts from cosmic projectiles later filled by basaltic lava flows from volcanic eruptions. Basaltic lava flows on the basin floors give maria their dark albedo appearance.
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021-The Moon from Clem-Aristachus-PIA00090.jpg042 - Aristarchus Crater (false colors)53 visiteThe Aristarchus region is one of the most diverse and interesting areas on the Moon. About 500 Clementine images acquired through three spectral filters (415, 750, and 1000 nm) were processed and combined into a multispectral mosaic of this region. Shown here is a color-ratio composite, in which the 750/415 ratio controls the red-channel brightness, it inverse (415/750) controls the blue, and the 750/1000 ratio controls the green. Color ratios serve to cancel out the dominant brightness variations and topographic shading, thus isolating the color differences related to composition or mineralogy. The Aristarchus plateau is a rectangular, elevated crustal block about 200 km across, surrounded by the vast mare lava plains of Oceanus Procellarum. Clementine altimetry shows that the plateau is a tilted slab sloping down to the northwest, that rises more than 2 km above Oceanus Procellarum on its southeastern margin. The plateau was probably uplifted, tilted, and fractured by the Imbrium basin impact, which also deposited hummocky ejecta on the plateau surface. The plateau has experienced intense volcanic activity, both effusive and explosive. It includes the densest concentration of lunar sinuous rilles, including the largest known, Vallis Schroteri, which is about 160 km long, up to 11 km wide, and 1 km deep. The rilles in this area begin at 'cobra-head' craters, which are the apparent vents for low-viscosity lavas that formed vents for 'dark mantling' deposit covering the plateau and nearby areas to the north and east. This dark mantling deposit probably consists primarily of iron-rich glass spheres (pyroclastics or cinders), and has a deep red color on this image. Rather than forming cinder cones as on Earth, the lower gravity and vacuum of the Moon allows the pyroclastics to travel much greater heights and distances, thus depositing an extensive regional blanket. The Aristarchus impact occurred relatively recently in geologic time, after the Copernicus impact but before the Tycho impact. The 42 km diameter crater and its ejecta are especially interesting because of its location on the uplifted southeastern corner of the Aristarchus plateau. As a result, the crater ejecta reveal two different stratigraphic sequences: that of the plateau to the northwest, and that of the portion of Oceanus Procellarum to the southwest. This asymmetry is apparent in the colors of the ejecta as seen in this image, which is reddish to the southeast, dominated by excavated mare lava, and bluish to the northwest, caused by the excavation of highland materials in the plateau. The extent of the continuous ejecta blanket also appears asymmetric: it extends about twice as far to the north and east than in other directions, approximately following the plateau margins. These ejecta lobes could be caused by an oblique impact from the southeast, or it may reflect the presence of the plateau during ejecta emplacement. Two dark blue spots in the center of Aristarchus represent tan especially interesting discovery. The infrared spectral properties measured by Clementine are consistent with a composition of almost pure anorthosite, the primitive rock type produced by the lunar magma ocean. This is the first discovery of a major exposure of anorthosite in this region of the Moon, well within the boundary of the hypothetical Procellarum basin. Don Wilhelms (Geologic History of the Moon, USGS Professional Paper, 1984) proposed that the giant Procellarum basin entirely removed the upper anorthositic crust from the north-central nearside of the Moon.
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021-Vesta-3.jpgMoments of 4-Vesta52 visiteTo prepare for the Dawn spacecraft's visit to Vesta, astronomers used Hubble's Wide Field Planetary Camera 2 to snap new images of the asteroid. These images were taken on May 14 and 16, 2007. Each frame shows time in hours and minutes based on Vesta's 5,34-hour rotation period. Using Hubble, astronomers mapped Vesta's Southern Hemisphere, a Region dominated by a giant impact crater formed by a collision billions of years ago. The crater is 285 miles (456 Km) across, which is nearly equal to Vesta's 330-mile (530-Km) diameter.
Hubble's sharp "eye" can see features as small as about 37 miles (60 Km) across. The images show the difference in brightness and color on the asteroid's surface. These characteristics hint at the large-scale features that the Dawn spacecraft will see when it arrives at Vesta in 2011.
Hubble's view reveals extensive global features stretching longitudinally from the Northern Hemisphere to the Southern Hemisphere.
The images also show widespread differences in brightness in the east and west, which probably reflects compositional changes. Both of these characteristics could reveal volcanic activity throughout Vesta. The size of these different regions varies. Some are hundreds of miles across.
The brightness differences could be similar to the effect seen on the Moon, where smooth, dark regions are more iron-rich than the brighter highlands that contain minerals richer in calcium and aluminum. When Vesta was forming 4.5 billion years ago, it was heated to the melting temperatures of rock. This heating allowed heavier material to sink to Vesta's center and lighter minerals to rise to the surface.
Astronomers combined images of Vesta in two colors to study the variations in iron-bearing minerals. From these minerals, they hope to learn more about Vesta's surface structure and composition. Astronomers expect that Dawn will provide rich details about the asteroid's surface and interior structure.
MareKromium
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023-The Moon from Clem-SchroendingerBasin.jpg045 - Schroedinger Basin (detail mgnf)52 visiteDetail from the UV-VIS Clementine Camera of the floor of the basin Schrodinger, showing the coverage (inset strip) of the HR camera for comparison. The Dark Halo Crater (center at 76 South Lat. and 139 East Long.; 5 Km across) is a volcanic vent that erupted ash during the period of mare volcanism on the Moon, more than 3,5 BY ago.
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033-The Moon from Clem-Aristarchus-3.jpg041 - Aristarchus and Vallis Schroteri53 visiteThe plateau of the Aristarchus Crater has experienced intense volcanic activity, both effusive and explosive.
It includes the densest concentration of Lunar "sinuous rilles" ("snake-like" valleys) including the largest known, Vallis Schroteri, which is about 160 km long, up to 11 km wide and 1 km deep.
The rilles in this area begin at cobra-head craters, which are the apparent vents for a dark mantling deposit covering the plateau and nearby areas to the North and East.
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06-Oceanus Procellarum.jpgOceanus Procellarum68 visiteCaption NASA originale:"Northward oblique view of the Marius Hills and Oceanus Procellarun on the Moon taken by LO 2. The hills are named after the 41 Km diameter crater Marius, at the upper right at 11,8N, 50,8 W and are thought to be volcanic domes, plugs and cones. Note the wrinkle ridges which also stretch across the image (Lunar Orbiter 2, frame M-213)".
Location & Time Information
Date/Time (UT): 1966-11-25 T 14:16
Distance/Range (km): 139
Central Latitude/Longitude (deg): +07.96/307.23
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088-SOL932-McMurdo_L257F-A814R1_cbr2-00.jpgMc Murdo Panorama (1)76 visiteCaption NASA originale:"This beautiful scene reveals a tremendous amount of detail in Spirit's surroundings. Many dark, porous-textured volcanic rocks can be seen around the Rover, including many on Low Ridge. Two rocks to the right of center, brighter and smoother-looking in this image and more reflective in infrared observations by Spirit's Miniature Thermal Emission Spectrometer, are thought to be meteorites. On the right, "Husband Hill" on the horizon, the rippled El Dorado sand dune field near the base of that hill and lighter-toned Home Plate below the dunes provide context for Spirit's travels since mid-2005. Left of center, tracks and a trench dug by Spirit's right-front wheel, which no longer rotates, have exposed bright underlying material. This bright material is evidence of sulfur-rich salty minerals in the subsurface, which may provide clues about the watery past of this part of Gusev Crater".
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12-Davy Crater Chain.jpgThe "Davy Crater Chain" from Lunar Orbiter 4 - A comet impact?102 visiteCaption NASA originale:"Lunar Orbiter 4 image of the Davy Crater Chain on the Moon. The chain stretches from Davy Y at left to the large, bright Davy G (diameter 15 Km). Note the even spacing of the craters. The chain may be the result of secondary impacts, volcanic activity, or an impactor which broke apart shortly before impact, similar to Comet Shoemaker/Levy 9 on Jupiter. North is up (Lunar Orbiter 4, frame 108-H2)".
Location & Time Information
Date/Time (UT): 1967-05-18 T 17:16:51
Distance/Range (km): 2719
Central Latitude/Longitude (deg): -14.26/357.64
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16-Lunar Alps_H_SEMG9R7X9DE.jpgThe Lunar Alps103 visiteOriginal caption:"The European Alps were formed over millions of years by slow-moving sections of Earths crust pushed together, squeezing the land to form a giant arc of upthrust mountains, but the Lunar Alps were formed in an instant. It is thought that the Moon collided with a huge object, such as an asteroid, 3850 million years ago. The collision formed a huge crater, about 1000 Km in diameter. This crater was later filled with basaltic lava, forming the dark circular basin known as Mare Imbrium (Sea of Rains). After the explosive collision, fragments, rocks and dust fell back to the surface. While there is considerable debate as to the actual mechanism which formed the concentric rings, it is agreed they are not 'fallback' material. Some scientists argue that the the impact caused the lower layers to act as a liquid and that the rings then 'froze' in place. A flood of lava covered the lower inner one, but the outer one remains as a series of arc-shaped mountain ranges.
In places these mountains rise over 3000 metres. Their inner walls are steep and well defined, but their outer slopes become more broken as elevation decreases away from the impact site. Early European astronomers named them after familiar mountain ranges, such as the Juras, the Apennines and the Alps.
Seen in this image, Vallis Alpes (Alpine Valley) is a spectacular feature that bisects the Montes Alpes range. This valley was discovered in 1727 by Francesco Bianchini. It extends 166 kilometres from Mare Imbrium, trending north-east to the edge of the Mare Frigoris (Sea of Cold). The valley is narrow at both ends and widens to about 10 kilometres across.
The valley floor is a flat, lava-flooded surface that has narrow sinous rille running down the middle. It is generally considered to be a 'graben', an area between two parallel faults which has dropped below the surrounding area. This is believed to have formed after the formation of the basin, but before the full maria lava flows. The rille corresponds to a lava tube formed in a later geological episode by high-speed and low viscosity magma.
"SMART-1 is studying the signature of violent processes that took place during the formation of these giant impact basins, as well as the sequence of late volcanic history over the lunar surface until 3000 million years ago, said ESAs SMART-1 Project Scientist Bernard Foing.
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26-Lunar Highlands.jpgLunar Highlands66 visiteThese two images, taken by the advanced Moon Imaging Experiment (AMIE) on board SMART-1, show the difference between lunar highlands and a mare area from close by.
The image on the left, showing highlands, was obtained by AMIE on 22 January 2006, from a distance of about 1112 kilometres from the surface, with a ground resolution of 100 metres per pixel. The imaged area is centred at 26 South and 157 West.
The image on the right, showing a mare, was taken on 10 January 2006, from a distance of about 1990 kilometres and with a ground resolution of 180 metres per pixel. The imaged area is centred at 27.4 North and 0.8 East.
Already when looking at the Moon with the naked eye, it can be seen that there are bright and dark areas on its surface. Centuries ago, the dark areas were called 'maria', presumably assuming that the observer would be seeing water oceans. Today we know that there is no liquid water on our satellite. However, telescopic observations showed that the maria are very flat, and are very different from the so-called highlands. The highlands are heavily cratered and mountainous.
We have learned that the maria are relatively young areas on the Moon which were generated after very large impacts penetrated the lunar crust and excavated basins. During later volcanic episodes, liquid magma came to the surface and filled these basins. When it cooled down and solidified, it formed the large flat areas we can still see today. As this happened in comparatively recent times, the number of impact craters is far less than in the highland areas.
From the two images it is possible to see how highlands present a very irregular topography and many craters, while the mare area is comparatively flat and shows a much smaller number of craters.
The images are raw data and no flat field or other corrections have been applied.
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