| Comments |
| Lunation | 1075 |
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| Phase | Waxing Gibbous |
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| Age | 12.22d |
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Distance
Light Time
(from earth) | 378,343 km
s |
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| Elongation | ° |
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| % Illuminated | 86.8% |
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| Morning Terminator Colongitude (λ E) | 53.6° |
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| Evening Terminator Colongitude (λ W) | 233.6° |
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| Libration in Latitude | -6° 11' |
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| Libration in Longitude | -6° 3' |
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| Magnitude | -11.1 |
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| Angular Size | 31.58' |
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| Altitude | 58° 15' |
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| Virtual Moon Atlas graphic |
My main goal for tonight was to see if I could see any of the men, women and animals in the moon. I accomplished that and a good bit more.
The image of the Man in the Moon is a pareidolia. Wikipedia says a pareidolia is
- Pareidolia
- (pronounced /pærɪˈdoʊliə/) is a psychological phenomenon involving a vague and random stimulus (often an image or sound) being perceived as significant.Common examples include seeing images of animals or faces in clouds, the man in the moon, and hearing hidden messages on records played in reverse. The word comes from the Greek para- ("beside", "with", or "alongside"—meaning, in this context, something faulty or wrong (as in paraphasia, disordered speech)) and eidolon ("image"; the diminutive of eidos ("image", "form", "shape")). Pareidolia is a type of apophenia.
I have never seen any of the images in the Moon so am giving it another try tonight while the Moon is full.
Full Moon |
Man Carrying Sticks with Dog |
Man in the Moon |
Woman |
Face |
Rabbit |
| images from Wikipedia |
| Terminator |
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| In Shadow | Feature | In Sunlight |
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| | J. Herscel | >>> |
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| | Harpalus | >>> |
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| | Sharp | >>> |
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| | Mairan | >>> |
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| <’<< | Montes Agricola | >>> |
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| | Vallis Schroter | >>> |
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| | Herodotus | >>> |
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| | Aristarchus | >>> |
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| | Marius | >>> |
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| <<< | Reiner | |
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| | Hansteen | >>> |
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| | Billy | >>> |
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| | Mersenius | >>> |
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| <’<< | Schicard | >>> |
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| | Schiller | >>> |
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| | Segner | >>> |
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| | Zucchus | >>> |
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| | Betinus | >>> |
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I started off the night with some naked-eye observing of the Moon to identify as many of the images on the surface of the Moon as I could.
We spent a lot of time tonight in the southern highlands around Schiller and in Oceanus Procelarum near Aristarchus. I can’t remember a time when the southern highlands has looked as clear and was as easy to navigate as it was tonight.
Schiller looks strange sitting down there near the south lunar pole. It is long and thin with a bulge near it’s center while everything around it is round. Peter speculated that it was caused by multiple impacts and I said that if that was the case then the impacts must have occurred simultaneously as there was no indication of the walls of any of them on the crater floor. Peter found some lines in the surface that suggested to him a larger old crater surrounding and nearly tangent to Schiller. I could follow his lines although we didn’t always agree on exactly where they went. I had brought the Moon Observer’s Guide with me so got it out to see what Grego has to say. Schiller, a prominent, somewhat elongated walled plain (171 x 71 km), comes into view in the southwest. Possibly a line of three joined craters (perhaps resulting from a simultaneous multiple impact), the broader, smoother southern plain of Schiller narrows in the north, where a couple of larhe ridhes cross the floor from north to south. Schiller itself lies on the northeasterb margins of a large but unnamed (350 km diameter) multiringed badin, unofficially designated the Schiller Annular Plain. This feature is visible toward the end of day ten and during day eleven. Looking at the inner ring below Schiller I had the impression that it was over top of a pair of tangent young craters. It looked to me as though cookie dough had been draggled onto a cold surface and hardened there. It does not appear to be continuous but rather three sections of draggle. Peter bumped the magnification up to 237x and for me this impression was even stronger. That would mean that first came the Schiller Annular Plain then Schiller then the two young craters and lastly this mound that we are attributing to an inner rim of the plain and that can’t be. We looked it it an a lunar atlas app on Peter’s iPhone and there the draggles appear to be interrupted by the later-occurring craters.
Geologic Lunar Atlas (Southern Hemisphere plate) graphic
Map Key
- Nc
- CRATER MATERIAL YOUNGER THAN NECTARIS BASIN BUT OLDER THAN IMBRIUM BASIN -- Few rim or interior textures visible except in largest craters; queried where could be units pNc or Nbc
BASIN MATERIALS
- Ioc
- MATERIAL OF ORIENTALE-BASIN SATELLITIC CRATERS -- Grouped in clusters and chains peripheral to Orientale basin and in some outlying areas.
Interpretation: Secondary impact craters or Orientale basin; queried where could be primary craters
- Ioho
- Outer facies -- Discontinuous deposits adjacent to Orientale secondary craters (mapped and unmapped) commonly having basin-radial ridges and grooves.
Interpretation: Mostly ejecta formed by closely spaced secondary impacts
PROBABLE BASIN-RELATED MATERIALS
- Ip
- PLAINS MATERIAL - Light-colored, smooth, mostly flat-surfaced deposits having superposition relations and crater densities indicating Imbrian age.
Interpretation: Primary and secondary ejecta of Orientale and Imbrium
The large-scale map in the corner of that plate names the basin as the Schiller-Zucchius Basin which is contained within the Orientale Basin.
Geologic Lunar Atlas (Southern Hemisphere plate) graphic
The chart collar contains the following explanatory text:
BASIN MATERIALS
Most lunar impact excavations larger than 260 km in diameter and some smaller ones possess one or more raised inner rings and so are called multiring basins (Hartmann and Kuiper, 1962). Other circular features this size and larger probably also originally had multiple rings, but the inner rings are now obscured. Many terra materials mapped here can be identified with specific basins, and the remainder are also believed related to basins or craters. Formation of two large, ancient (pre-Nectarian) basins (South Pole-Aitken and Australe) raised the hightest mountains, three Nectarian basin impacts and the later Orientale basin impact outside the map area deposited extensive material within it; and other pre-Nectarian, Nectarian, and Imbrian basins in and outside the area contributed to its geomorphic and stratigraphic framework.
RING IDENTIFICATION AND DATING OF BASINS
The largest and oldest basin so far documented on the Moon is South Pole-Aitken (Stuart-Alexander, 1978), also called Big Backside basin or Aitken-Backside basin. The basin rim is defined by a discontinuous mountain ring 2200 km (Stuart-Alexander, 1978) to 2500 km (this report) in diameter. The larger figure is based on an interpretation that massifs (map symbol pNbm) and adjacent rugged material (map symbol pNbr) between lat 75° S., long 40° W. and the unphotographed zone are part of the rim, and that other massifs and rugged material entirely on the far side constitute a second ring 250 to 500 km inside the rim. Alternatively, all the basin massifs and rugged basin material may constitute a very broad rim whose mean diameter would be about 2200 km. The rugged basin material as far north as lat 63° S. on the near side may also be part of the rim flank. The near-side massifs were discovered by Earth-based telescopic observations, and their connection with a large basin beyond the lunar limb was predicted by Hartmann and Kuiper (1962). The South Pole-Aitken basin is also expressed as a giant depression detected by Zond 6 and 8 photographic altimetry (Rodinonov and others, 1971, 1977) and Apollo laser altimetry (Wollenhaupt and Sjorgren, 1972; Bills and Ferrari, 1975; Kinsler and others, 1975). We estimate the basin center to be located at about lat 56° S., long 180°. Numerous small mare patches, partly localized in superposed basins and craters, occupy the basin inside the inferred inner ring.
At least four other basins centered in the map area are also pre-Nectarian in age. Planck, Poincare, and Schiller-Zucchius (“basin near Schiller” of Hartmann and Kuiper, 1962) are small, double-ring basins identified as pre-Nectarian on the basis of degraded superposed craters. The fourth, Australe, is named for many small, discontinuous patches of mare material collectively known as Mare Australe. The circular pattern of the mare patches and an enclosing arcuate chain of massifs near long 120° E led to recognition of Australe as a basin (Stuart-Alexander and Howard, 1970). This chain apparently indents the rim of South Pole-Aiken, a relation which suggests that Australe is the younger basin; exceptionally large massifs in this chain may have been uplifted by impacts. Additional massifs and elevated tracts of rugged basin material and other units appear to define two interior Australe rings.
Four additional pre-Nectarian basins have been tentatively identified. A single ring about 700 km in diameter delineates a heavily cratered probable basin here named Mutus-Vlacq according to the convention of designating basins after supposed (unrelated) features (Wilhelms and El-Baz, 1977). This postulated rim accounts for small mounds of basin massif material (map symbol pNbm) and other elevated basinlike terrain (map symbol pNb) near lat 62° S., long 35° E., and the basin may have acted as a catchment for an otherwise puzzling concentration of Nectarian plains materials (map symbol Ntp). The smaller Sikorsky-Rittenhouse and Amundsen-Ganswindt basins show traces of inner rings (not mapped), but their identity as basins and their ages are uncertain because of burial by deposits from the Schrodinger basin. Parts of their postulated rings -- especially those of Sikorsky-Rittenhouse (“unnamed A” basin of Hartmann and Wood, 1971, later withdrawn from the list of basins by Wood and Head, 1976) -- could instead be part of the Sout Pole-Aitken basin. Finally, an indistinct possible basin named Pingre by Hartmann and Kuiper (1962) and Pringre-Hausen in this report underlies deposits of the crater Hausen and of the basins Orientale, Bailly, and Mendel-Ryberg.
Three basins centered in the map area are believed to be Nectarian in age -- younger than the Nectaris basin and older than the Imbrium basin on the northern near side. The three differ greatly in degree of degradation. An indistinct, large basin, here named Mendel-Rydberg, was called the “SE limb basin” by its discoverers Hartman and Kuiper (1962), who identified on telescopic photographs two of the three rings mapped ere. The nearby Bailly basin is smaller and younger. Both Bailly and Mendel-Rydberg are severely degraded as a consequence of burial by deposits from Orientale and the crater Hausen but are thought Nectarian in age because no pre-Nectarian craters appear to be supported. The Schrodinger basin is younger still, and its deposits cover much of the map area. The density of superposed craters too small to map here (<20 km) suggests an age of late Nectarian, but this fresh-appearing basin could be lower Imbrian as no definite Nectaran craters are superposed. The inner ring consists of rugged crags similar to those of lunar central peaks (Hartmann and Wood, 1971) and is believed related in origin to such peaks although its exact formative process is uncertain (Hodges and Wilhelms, 1978). The other, terraced ring resembles the rims of craters (Howard and others, 1974, fig. 4) and must similarly be the limit of the excavated cavity modified by slumping.
INTERPRETATION OF CIRCUM-BASIN DEPOSITS AND SATELLITIC CRATERS
Deposits from basins outside the map area dominate more than half of its northern border zone. Emplacement processes of basin deposits have been deduced from the well-exposed, well-photographed Orientale materials. The inner facies of the Hevelius Formation (map symbol lohi) is a continuous, strongly lineated, apparently thick deposit that extends back to the Orientale basin rim (Montes Cordillera) north of the region and that, accordingly, must contain much primary basin ejecta. This deposit apparently flowed along the surface at least part of the distance from the rim, for parts of it piled up as transverse ridges against the southeast wall of the crater Inghirami and other obstacles (McCauley, 1968; Scott and others, 1977). The relatively smooth, nonlineated facies of the Hevelius formation (map symbol lohn) is gradational with the coarsely textured inner facies and in part forms raised lobes bounded by distinct scarps (Moore and others, 1974, figs. 6, 7) that suggest flowage of a viscous, fluidlike material.
Secondary impact apparently emplaced most deposits beyond the inner and nonlineated facies of the Hevelius Formation and beyond comparable, though less well preserved materials of other basins (Moore and others, 1974; Oberbeck and others 1974, 1975; Morrison and Oberbeck, 1975; Oberbeck, 1975; Wilhelms, 1976). Satellitic craters of Orientale (map symbol loc) so closely resemble secondary impacts of large lunar craters (Offield, 1971; Wilhelms and McCauley, 1971; Oberbeck and Morrison, 1974; Wilhelms, 1976) that their identity as Orientale basin secondaries seems certain. Basin-radial ridges and smooth deposits commonly lie on the distal side of the secondary crater and constitute a discontinuous unit called the outer facies of te Hevelius Formation (Scott and others, 1977(; most of these deposits presumably consist of secondary ejecta. East of long 20° E. are corresponding, though less fresh, features of the Nectaris basin, indluding secondary craters (part of map unit Nbc) andridged deposits (Janssen Formation, Stuart-Alexander, 1971). The Nectarian basin deposits (map symbol Nbl) and clustered secondary craters (map symbol Nbc) near the map border between long 142° and 176° W. are related to the Apollo basin centered 300 km nort of the area. We have mapped the Apollo-related units as Nectarian based on their morphology ut the basin may instead be pre-Nectarian (Stuart-Alexander, 1978.
Other probably secondary craters throughout the map area, though not closely satellitic to basins, have been traced to their sources by orientation. Secondaries of Schrodinger (Nectarian) are easily identified as far as three basin diameters from its rim by linear, groovelike shapes and the concentration in few azimuthal directions that characterize the basin. A few probable Nectarian secondary craters in the vicinity of the Apollo deposits are more closely radial to the distant Hertzsprung basin, 1400 km north (lat 1° N., long 129° W.), than to Apollo. Numerous large chains east of the crater Clavius, also mapped as Nectarian basin secondaries, are radial to the distant Humorum basin (lat 24° S., long 39° W.) and may be parts of its secondary field although their nature is problematic. Finally, outliers of the large field of secondary impact craters of the Imbium basin (map symbl Iic) occur in the north part of the map area.
PROBABLE BASIN-RELATED MATERIALS
Additional units interpreted as basin related occur among and beyond the secondary craters and lineated deposits. The inner, nonlineated, and outer facies of the Hevelius Formation grade in places into smooth-surfaced plains-forming material of Imbrian age that occupies depressions (map symbol Ip). Gradations of the smooth plains material with primary and secondary basin materials suggest that the plains material here consists of ejecta and not volcanic material, as has een proposed for some plains (for example, Wilhelms and McCauley, 1971; Neukum, 1977). Similar plains of Imbrian age that are distant from the Orientale basin may be ejecta of Imbrian-basin secondary craters or of large Imbrian primary craters. Nectarian terra-mantling and plains material (map symbol Ntp) is probably similar in origin to these Imbrian deposits for it is concentrated around Nectarian basins (Nectaris, Schrodinger, Mendel-Ryberg, and Apollo), large craters (Clavius), and satellitic and distant secondary craters of Nectarian basins including those tentatively ascribed to Humorum. Age assignment of plains and terra-mantling materials depends partly upon crater counts made on photographs of uneven quality, so that some patches mapped as Imbrian could be Nectarian.
The outer facies of the Hevelius Formation grades outward into less heavily mantled terrain with fewer lineations and pits that is mapped as composite units -- Imbrian and Nectarian with fewer terra (map symbol INt) where the units visible under the Orientale textures are mostly Nectarian, and Imbrian and pre-Nectarian terra (map symbol IpNt) where the underlying material is mostly pre-Nectarian. Much terrain outside te distinctive materials of Nectarian basins, though mostly lacking conspicuous lineations and pits, also seems subdued and a mantle that is gradational with the Nectarian basin materials and accordingly is mapped as Nectarian and pre-Nectarian terra (map symbol NpNt). Visibility of textures and therefore mapping of many lunar material units depends both on photographic quality and degree of degradation. For example, the outer facies of the Hevelius Formation and the Orientale-related composite units may be more extensive than mapped, especially on the far side where photographs are poorest. Also, time-related degradation has probably blurred Nectarian textures that once resembled those of Orientale, so that the well-defined basin-related province is less extensive relative to the probable basin-related province (fig.2) for the Necctarian system than for Orientale. The degradation process has proceeded even further among pre-Nectarian units, where the rugged basin material (map symbol pNbr) and even more poorly defined, generally low-lying unit called pre-Nectarian terra material (map symbol pNt) occupy the positions of the much more distinctive and varied younger basin units that they presumably once resembled. Contributions to the pre-Nectarian terra unit from the various pre-Nectarian basins and craters are not distinguished on this map because of inadequate photography and exposure.
Two more distinctive but less extensive units may also be related to basins although their origin is uncertain. The exposure of grooved material (map symbol IpNg) in certain areas near long 160° E. and the better exposures immediately to the north (Stuart-Alexander, 1978) are antipodal to the Imbrium basin and have been interpreted as the products of the impact of converging Imbrium ejecta (Moore and others, 1974) or shaking induced by seismic waves from Imbrium (Schultz and Gault, 1975). Most fractured crater floors (map symbol Ifc), the other areally restricted unit, are probably products of extensive floor uplift, and common phenomenon in and near basins (Pike, 1971; Schultz, 1976), but some peripheral to the Orientale deposits could be Orientale impact melt, as observed elsewhere in similar positions (Moore and others, 1974).
CRATER MATERIALS
Primary impact craters with a complete range in ages dot the map area, as they do all lunar highlands. The materials of these craters are still perceived much as described on earlier maps such as that by Wilhelms and McCauley (1971).
The usual Imbrian crater Antoniadi (lat 69.5° S., long 172° W.), 150 km wide, deserves special mention for two reasons. First, it is ringed by an unusually extensive and dense array of secondary impact craters (map symbol Isc). Second, it has booth a central peak and an inner ring of peaks, making it transitional between craters and multiring basins (Hartmann and Wood, 1971; Hodges and Wilhelms, 1978).
In summary, thegeology of the terra can be accounted for by a succession of large and small impacts that excavated basins and craters, deposited the ejecta where it cratered and redistributed the preimpact terrain. Basins were also favorable sites for subsequent internal activity, such as crater-floor uplift and mare volcanism.
MARE AND OTHER DARK MATERIALS
Although, in general, the near side of the Moon has more extensive mare material than the far side, the reverse is true in this southern area. Except near the east limb, that part of the near side within the map area is nearly devoid of mare material; whereas the far-side part contains dozens of mare patches. This concentration results from depressions afforded by the Australe and South Pole-Aitken basins and the smaller basins and craters superposed on them.
Three age groups of mare material have been mapped (two in fig. 2), each of which represents stratigraphically complex units with a range of ages. The oldest group (map symbol Im1) was early recognized as exceptionally old for lunar mare material (Stuart-Alexander and oward, 1970). It is older than many upper Imbrian crater materials (map symbol Ic2) and than all known mare materials of the central near side. It is lighter in color than most other mare units and is gradational in color and crater density with the terra and plains materials. The intermediate mare material mapped here (map symbol Im2) substantially overlaps typical near-side material in age, although its full age range has not been determined. The distinction between mare units is clear over most of Mare Australe but can be made only tentatively in the poorly photographed area in the South Pole-Aitken basin. The youngest unit (map symbol Elm) is partly or entirely Eratosthenian. Small mare domes (map symbol Imd) and similar swellings that may be domes are mantled terra (map symbol Imd?) also mapped, as are small patches of dark mantling material (Id) surrounding their apparent source vents in the Schrodinger basin.
A few large wrinkle-ridge structures traverse part of Mare Australe but wrinkle ridges and fault grabens are rare in the map area, in contrast with their abundance in and near the large nearside lunar maria. This distribution supports an inference that most nonimpact compression and extension of the lunar crust relate to crustal loading by mare basalts (Solomon and Head, 1979).
GEOLOGIC HISTORY
The detectable history of the region begins with the largest event inferred from visible landforms on the Moon, the impact that raised the massive South Pole-Aitken rim, excavated most of the far-side part of the map area, and probably covered the near-side part with excavated debris. A second large impact formed the adjacent Australe basin, and smaller pre-Nectarian impacts excavated at least three basins (Poincare, Planck, and Schiller-Zuccius), possibly four others tentatively identified, and perhaps still others that have been obscured. The Nectarian Period began with the formation of the Nectaris basin, which is centered outside the map area but strongly influenced it by covering and cratering many pre-Nectarian craters and basin deposits. Later in Nectarian time, the Apollo and Humorum impacts also deposited materials and formed secondary craters in the north part of the area, and the Mendel-Rydberg, Bailly, and Schrodinger basins and the large crater Clavius were formed within it. Schrodinger, with its distinctive, linear secondary-crater chains and pronounced double-ring structure, strongly affected the appearance of the southern far side. In the Imbrian Period, ejecta from the distant Imbrium basin formed scattered secondary craters, Orientale basin deposits blanketed a huge region on the west limb including the Mendel-Rydberg and Bailly basins, and Orientale ejecta formed many secondary craters beyond this blanket. Mare volcanism left still-visible traces in the lowlands of the South Pole-Aitken and Australe basins beginning about the time of the Orientale impact, continuing through the Imbrian Period, and locally extending into the Eratostenian. Impact events, which in Imbrian time produced the crater-basin Antoniadi and other large craters, continued at a low rate through the Eratosthenian and Copernican Periods.
{MORE TO FOLLOW}
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