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APOLLO 15 AS 15-9328.jpgAS 15-9328 - Bessel Crater58 visiteOutcrops of layered rock are strikingly evident in the upper part of the far wall of the crater Bessel (17- Km diameter) in South-Central Mare Serenitatis. The outcrop is most evident where it forms shadows; however, the dark debris that streams downslope from the layered rock is visible even on parts of the crater wall where the Sun has washed out all details of relief. The outcrop is at a uniform distance below the crater rim, indicating that the strata are horizontal. Thus, Bessel furnishes convincing evidence that mare surfaces are underlain by dark layered rock. The dark rock is now known to be basalt that accumulated as successive flows or layers of lava.
Bessel is youthful enough that boulders are abundant on its rim and floor.
An anomalously high number of boulders is visible in and around the 750-m diameter crater (arrow) on the floor.
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APOLLO 15 AS 15-9874.jpgAS 15-9874 - Dawes Crater58 visiteThis is a near vertical view of the crater Dawes, 18 Km in diameter. Morphologically it is typical of many lunar craters in the 15- to 20-Km size range. It lacks terraced walls and distinct central peaks but has an extremely rough floor. Small terracelike structures on the crater floor (upper left, lower right) occur where the wall is bowed outward and probably represent slump deposits where portions of the crater wall have collapsed into the crater. Local stratigraphy is revealed in the walls of the crater, and material of different albedo is seen streaming down into the crater from various levels. The dark layer clearly visible in the upper part of the crater wall represents the thin mare deposits in this part of Northern Mare Tranquillitatis. The lighter gray material below it is a combination of underlying submare material and talus from units higher on the crater wall. The highest unit (white and gray) probably represents the ejecta blanket and may consist primarily of lighter lunar crustal material excavated from beneath the mare.
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APOLLO 17 AS 17-2265.jpgAS 17-2265 - Proclus Crater58 visiteThis oblique view looks South over the 26-Km-diameter crater Proclus in the highlands at the Western edge of Mare Crisium. Proclus is a young rayed crater that is distinctive because of the marked asymmetry of its ray system-a characteristic visible even in Earth-based telescopic views. The excluded zone is along the South-West edge (top of photograph) but is visible in this moderate Sun photo only as a slight albedo change. Laboratory experiments suggest that a low trajectory angle might account for the asymmetry. A number of large blocks can be seen at the edge of the crater rim. The exceptionally large block (arrow) is about 200 mt wide and, judging from the length of the shadow it casts, nearly as high. As in several other craters shown in this chapter, a darker layer is present in the upper part of the crater wall.
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Rhea-N00064799-A.jpgMoments of Rhea (1) - context image58 visitenessun commento
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M-008-3.jpgM 8 - The "Lagoon" Nebula58 visite"...But now we are...dead to that which held us captive, so that we are slaves not under the old written Code, but in the new Life of the Spirit..."
Romans - 7:6
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APOLLO 15 AS 15-9299.jpgAS 15-9299 - Le Monnier Crater58 visiteOn January 16, 1973, the Soviet unmanned roving vehicle Lunokhod 2 was landed by Luna 21 in or near this area in the South-Eastern part of the crater Le Monnier. This crater is a large (61 Km) pre-Imbrian crater cut into terra at the Eastern edge of Mare Serenitatis before Serenitatis was flooded by mare laves. Part of Le Monnier's Southern wall fills the lower part of the picture. A conspicuous chain of elongate depressions has formed in the lava-filled floor of the crater. The chain trends 22 Km northward and its pattern is quite surely controlled by an underlying fracture system. Regionally, the inferred fracture system is concentric to the grossly circular Serenitatis Basin and in this area trends Northward. No comparably young structural features having the same trend cut the terrae surrounding Le Monnier. However, older structures having this trend occur in the southern and northern walls and rims of Le Monnier. The aligned depressions on the mare are mostly 300 to 400 mt wide and 30 to 60 mt deep. The three deepest stretches are 1 to 2 km long and about 50 to 65 m deep. These depressions probably were the locus of fissure eruptions of mare basalt. Withdrawal of the last lava back into the fissure may have created subsurface voids into which collapse took place, causing the depressions and accounting for the absence of raised rims on the depressions.
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APOLLO 17 AS 17-3125.jpgAS 17-3125 - Rimless crater58 visiteThe very young rimless crater near the center of this picture is located near the area where Oceanus Procellarum and Mare Imbrium join. The crater apparently formed in regolith-covered mare basalt. It differs from lunar impact craters of comparable size and age by its lack of a raised rim, surrounding ejecta deposit, or associated secondary impact craters. In addition, its interior walls do not show the steep slopes with craggy outcrops of rock in their upper parts, nor the streams of debris-avalanche deposits and talus that are usually seen in the walls of impact craters of comparable age and size.
Judging from the clear and sharply formed pattern of concentrically curved grooves and scarps that surround the hole, the material near this depression has apparently subsided into a subsurface void. Because of the extreme rarity and inferred short lifetime of steep slopes on the Moon, the latest subsidence must have taken place very recently, after most of the 50- to 300- m diameter craters that densely pepper the nearby mare surface were formed. Movement of the regolithic debris layer during subsidence apparently smoothed out most, if not all, of the craters that must have existed near the depression. Now the depression is surrounded by low, curved fault scarps and narrow, curved grooves that may be fault troughs (grabens) or may represent drainage of regolithic debris into cracks that opened in the underlying sagging basalt rock. The few craters that have formed on the subsided surface compare in density to the craters formed on the cluster (arrow) of Aristarchus secondary impact craters and associated herring- bone ridges; comparable ages for the Aristarchus secondary features and the depression are thus indicated. The subsidence was triggered either by the ground shock or seismic wavetrain generated when Aristarchus was formed 300 km to the west, or by the impacts of the secondary features.
The subdued depression in the upper left may be a similar older feature that was flooded by a later lava flow that now covers the area. The density of craters within the depression and the density on the surrounding lava are comparable. Alternatively, the subsidence there may have been incomplete; however, there is no sign that this subsidence is as young as that in the deeper crater
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APOLLO 16 AS 16-120-19268.jpgAS 16-120-19268 - King Crater58 visiteThe similarity in appearance of the Southern part of the central peak and the slump terraces on the Southern wall of the crater is emphasized in this oblique view of the crater King.
The parallelism of the two arms of the central peak and the Southern segment of the peak suggests that the unique shape of the structure is caused by a preexisting tabular body that was excavated during the formation of the crater.
Numerous comical structures with summit pits are present on the crater floor in the lower right part of the photograph.
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North_Polar_Features-North_Polar_Margin-PIA08705-2.jpgThe North Polar "Margin" (2 - Original NASA/JPL/ASU b/w Frame)58 visiteImage information: VIS instrument;
Latitude: 81,1° North;
Longitude: 299,2° East:
Resolution: 20 meter/pixel.
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APOLLO 17 AS 17-2773.jpgAS 17-2773 - Overlapping Craters58 visiteThis pair of overlapping medium-sized craters illustrates some of the criteria used to determine relative ages: material ejected from the larger polygonal crater on the left partially fills the smaller crater on the right; thus, the crater on the left is younger. Furthermore, the wall of the large crater is complete, whereas the West wall of the smaller crater is absent, obviously having been destroyed by the larger crater.
Even if the 2 craters did not overlap, the sharp rim, terraced walls and prominent central peak of the larger crater clearly identify it as the younger of the two. The frames used in the stereogram were selected to show exaggerated relief, a technique very helpful to photointerpreters in determining shapes and relative elevations of surface features.
These 2 craters are located in the rugged terrain of the Far-Side highlands, approx. 250 Km north of Tsiolkovsky.
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APOLLO 16 AS 16-4531.jpgAS 16-4531 - Teophilus' "Peak"58 visiteA detailed view of part of the central peak complex of Theophilus. Central peaks are typical of most young, large impact craters on the Moon-and also of many manmade craters on Earth. From experimental data using controlled explosions, central peaks are known to consist of bedrock originally lying below the crater floor that, during the explosion, was uplifted, faulted, and folded by shock wave action. The irregular light-toned mountainous mass projecting above the floor of Theophilus is split into at least three enormous blocks separated by V-shaped structural valleys. Four or five circular craters without a prominent raised rim are located near or at the bases of the steep slopes. If these craters are endogenic vents rather than impact craters, their presence further suggests structural control along major fault planes. The planar walls of the northwest-trending valley contrast with other sloping surfaces of the central peak complex. They are steeper and, except for a few outcrops of protruding bedrock, are marked by linear grooves not unlike slickensides on many fault planes on Earth. Rock chutes do not seem to be a likely explanation for the grooves because there are no talus deposits or blocks at their lower ends. The debris cover is thin enough along the southern valley wall (top of picture) to show that the southern mountain block consists of layered rocks-at least five thick, light-toned layers alternate with thin, dark layers.
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OPP-SOL921-1F209944046EDN758ZP1131L0M1-1.jpgStar-Like Object? (context image) - Sol 92158 visiteDall'occhio sempre attento del Dr Gianluigi Barca, un nuovo (l'ennesimo) esempio di un probabile "oggetto simil-stellare" che osserva (da una distanza imprecisata ed imprecisabile in dettaglio, ma certamente non grandissima) le mosse del MER Opportunity, ormai molto vicino al grande e (speriamo e supponiamo) spettacolare Victoria Crater.
Nel successivo detail mgnf (abbiamo operato un super-stretching) si rende palese la sensazione che lo S.L.O., se realmente si tratta di un oggetto reale, produce "turbolenze" nell'atmosfera ad esso circostante.
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