The Moon is a truly fascinating object, and in this section you'll find an extensive number of high resolution lunar portraits covering many of the Moons most interesting formations. Most of the images have been taken from Barbados during 2006, but there is also a significant number taken from the UK during 2005-6. This section will be added to as new images are obtained.
About the images.
All the images below were taken with a Celestron C14 Schmidt Cassegrain and Lumenera LU075M or SKYnyx 2.0M cameras. All were processed in Registax 3 or 4, and all are multi-point align processed. The images were taken either from St.Phillip, Barbados, West Indies (13°06 N, 59°30' W) or Loudwater, South East UK (51°35 N, 00° 46 W.)
About the Text.
More than wanting to simply present "pretty pictures" of the lunar surface, one of the great fascinations for me is the geological history of these features which adds greatly to the interest of the images. Much of the text information below is was taken from Wikipedia. All text from wikipedia is freely available to others under the terms of the Wikipedia Free Documention License.. A direct link to all the original wikipedia articles is provided in the text.
Abulfeda is a lunar impact crater located in the central highlands of the Moon. To the northeast is Descartes crater, and to the south-southeast is Almanon crater. A chain of craters named the Catena Abulfeda runs between the southern rim of Abulfeda and the north rim of Almanon, then continues for a length of 210 kilometers across the Rupes Altai.
Both the south and northeast sides of the crater rim are overlain by multiple small craterlets. The inner wall is noticeably wider in the east, and shallow and worn to the north. The crater floor has been resurfaced, either by ejecta from the Mare Imbrium or by basaltic lava, and is relatively smooth and featureless. The crater lacks a central rise at the mid-point, which may have been buried. The inner sides appear to have been somewhat smoothed down, most likely as a result of minor bombardment and seismic shaking from other impacts in the vicinity. 2006/04/18. C14 @ f41. LU075M.
Aliacensis & Werner. Aliacensis is a lunar impact crater that is located in the rugged southern highlands of the Moon. The Werner is located just to the north-northwest, and a narrow, rugged valley lies between the two comparably-sized formations. The rim of Aliacensis is generally circular, with an outward bulge on the eastern wall. The inner wall has some slight terracing particularly in the northeast. There is a small crater located across the southern rim. The interior floor is generally flat, with a low central peak slightly offset to the northwest of the mid-point.
Werner shows little appearance of wear, and is much younger and less eroded that the other large craters in the surroundings. The interior wall is terraced, and there is a noticeable rampart on the exterior. There are several low rises on the crater floor and a notable central peak. Rev. T. W. Webb noted two very bright spots along the sides of this crater, more visible in larger aperture telescopes. The Clementine Lunar Atlas displays a patch of high albedo surface along the northern inner wall. 2006/04/19 & 2006/04/08. C14 @ F41. LU075M.
Alpetragius is a lunar impact crater located on the east edge of Mare Nubium, to the southwest of the much larger Alphonsus crater. In the southeast is the prominent Arzachel crater, and to the west lies the flooded Lassell crater. The most notable feature of this crater is the disproportionately large central peak, which forms a rounded rise that occupies almost the entire crater floor—one-third the crater diameter—and rises to a height of 2.0 km. There is evidence that this peak has been enlarged through volcanic eruptions, and there appears to be an eroded vent at its summit. The rim has fine terraces that slope down to near the edge of the central rise along the south and east sides. Alpetragius's outer wall is nearly round, with slight protrusions on the north and west sides. 2006/04/08. C14 @ F41. LU075M.
Alphonsus is an ancient impact crater on Earth's Moon that dates from the immediate post-Nectarian era some 3.5billion years ago. It is located on the lunar highlands on the eastern end of Mare Nubium, west of the Imbrian Highlands, and slightly overlaps the Ptolemaeus crater to the north. The surface is broken and irregular along this boundary. The outer walls are slightly distorted and possess a somewhat hexagonal form. To the northwest is the smaller Alpetragius crater.
A low ridge system of deposited ejecta bisects the crater floor, and includes the steep central peak. This pyramid-shaped formation rises to a height of 1.5 km above the interior surface. It is not volcanic in origin, but rather is made of anorthosite like the lunar highlands.
The floor is fractured by an elaborate system of rilles and contains three smaller craters surrounded by a symmetric darker halo. These dark-halo craters are cinder cone-shaped and are believed by some to be volcanic in origin, although others think they were caused by impacts that excavated darker mare material from underneath the lighter lunar regolith.
Alphonsus was one of the primary alternative landing sites considered for both the Apollo 16 and the Apollo 17 missions. The Ranger 9 probe impacted in Alphonsus crater, a short distance to the northeast of the central peak. 2006/04/19 & 20. C14 @ F41. LU075M.
Vallis Alpes (latin for"Alpine Valley") is a spectacular lunar valley feature that bisects the Montes Alpes range. It extends 166 km from the Mare Imbrium basin, trending east-northeast to the edge of the Mare Frigoris. The valley is narrow at both ends and widens to a maximum width of about 10 km along the middle stretch.
The floor of the Vallis Alpes is a flat, lava-flooded surface that is bisected by a very narrow, cleft-like rille. (This cleft is a well known and challenging target for telescopic observation from the Earth.) The sides of the valley rise from the floor to the surrounding highland terrain, a blocky, irregular surface. The southern face of the valley is straighter than the northern side, which is slightly bowed and uneven. The more rugged edges of the valley lie at the narrow west-southwest end that cuts through the mountain range. Most likely this valley is a graben that was subsequently flooded with magma. This valley was discovered in 1727 by Francesco Bianchini. 2006/04/19. 2007/03/26 C14 @ F41. LU075M.
Anaxagoras is a young lunar impact crater that is located near the north pole of the Moon. It lies across the larger and more heavily worn Goldschmidt crater. To the south-southeast is Epigenes, and due south is the worn remains of Birmingham.
Anaxagoras is a relatively recent impact crater that is young enough to still possess a ray system that has not been eroded by space weathering. The rays from the site reach a distance of over 900 kilometers from the rim, reaching Plato to the south.
The crater interior has a relatively high albedo, making it a prominent feature when the Moon is nearly full. (The high latitude of the crater means that the Sun always remains close to the horizon even at maximum elevation less than a day after Full Moon.) The interior walls are steep and possess a system of terraces. The central peak is offset from the crater mid-point, and joins a low range across the crater floor. 2006/04/18. C14 @ F41. LU075M.
Arago is a impact crater located in the western part of the Mare Tranquillitatis. The rim of Arago has a bulge in the western wall. There is a central ridge that runs toward the north wall. The surface of the mare nearby is marked by wrinkle-ridges, most notably to the east and southeast. To the north is a large lunar dome designated Arago Alpha (α). A similar-sized lunar dome is located an equal distance to the west, designated Arago Beta (β). 2005/11/20. C14 @ F41. LU075M.
Archimedes is a large lunar impact crater on the eastern edges of the Mare Imbrium. The diameter of Archimedes is the largest of any crater on the Mare Imbrium. The rim has a significant outer rampart brightened with ejecta and the upper portion of a terraced inner wall, but lacks the ray system associated with younger craters. A triangular promontory extends 30 kilometers from the southeast of the rim.
The interior of the crater lacks a central peak, and is flooded with maria. It is devoid of significant raised features, although there are numerous tiny meteor craters scattered across its floor. Scattered wisps of bright ray material lie across the floor, most likely deposited by the impact that created Autolycus crater. 2006/04/19 & 20. C14 @ F41. LU075M.
Aristarchus, Herodotus & Vallis Schroteri.
Aristarchus is a prominent lunar impact crater that lies in the northwest part of the Moon's near side. It is considered the brightest of the large formations on the lunar surface, with an albedo nearly double that of most lunar features. The feature is bright enough to be visible to the naked eye, and is dazzling in a large telescope. It is also readily identified when most of the lunar surface is illuminated by earthshine.
The crater is located at the southeastern edge of the Aristarchus plateau, an elevated area that contains a number of volcanic features, such as sinuous rilles. This area is also noted for the large number of reported transient lunar phenomena, as well as recent emissions of radon gas as measured by the Lunar Prospector spacecraft.
The brightest feature of this crater is the steep central peak. Sections of the interior floor appear relatively level, but Lunar Orbiter photographs reveal the surface is covered in many small hills, streaky gouges, and some minor fractures. The crater has a terraced outer wall covered in a bright blanket of ejecta, which spreads out into bright rays to the south and south-east. (These suggest that Aristarchus was most likely formed by an oblique impact from the northeast.) Observers have noted that the wall is roughly circular but has a somewhat polygonal shape.
The main reason for the crater's brightness is that it is a young formation, approximately 450 million years old, and the solar wind has not yet had time to darken the excavated material by the process of space weathering. The impact occurred following the creation of the Copernicus crater, but before the appearance of Tycho crater. Based on the asymmetrical spread of the ejecta, it was formed by an object that struck at a
The Vallis Schröteri is a sinuous valley located on a rise of continental ground, called the Aristarchus plateau. This is the largest such sinuous valley formation on the Moon. It begins at a 6 km diameter crater located 25 km to the north of Herodotus. (The start of the valley has been termed the "Cobra's Head" by some observers, due to its resemblance to a snake.) From the crater it follows a meandering path, first to the north, then setting a course toward the northeast, before finally bending back to the south until it reaches a 1 km high precipice at the edge of the Oceanus Procellarum. The valley has a maximum width of about 10 km, then gradually narrows to less than a kilometer near its terminus.
The origins of this valley are believed to be volcanic. The interior floor has been resurfaced and is very level. However there is a slender rille located on the floor visible in large telescopes. 2006/04/21 & 2006/11/04. C14 @ F41. LU075M.
Aristillus is a prominent crater that lies at the southeast of Mare Imbrium. The rim of Aristillus crater has a wide, irregular outer rampart of ejecta that is relatively easy to discern against the smooth surface of the surrounding mare. The crater impact created a ray system that extends for a distance of over 600 kilometers. The rim is generally circular in form, but possesses a slight hexagonal shape. The inner walls of the rim have a terraced surface, and descend to a relatively rough interior that has not been flooded with lava. In the middle of the crater is a set of three clustered peaks, which rise to a height of about 0.9 km.
In the northern outer ramparts of Aristillus is a ghost-crater remnant. This is the protruding rim of an old crater that has been almost completely submerged by the lava flows of the surrounding Mare Imbrium. The southern end of the rim has been covered by the ejecta from Aristillus. Along the eastern inner wall and rim is an unusual narrow ribbon of dark material. 2006/04/19 & 2005/09/22. C14 @ F41. LU075M.
Aristoteles is a impact crater that lies near the southern edge of the Mare Frigoris, and to the east of the Montes Alpes mountain range. To the south of Aristoteles lies the slightly smaller crater Eudoxus, and these two form a distinctive pair. An arc of mountains between these craters bends to the west, before joining the walls.
Observers have noted the crater wall of Aristoteles is slightly distorted into a rounded hexagon shape. The inner walls are wide and finely terraced. The outer ramparts display a generally radial structure of hillocks through the extensive blanket of ejecta. The crater floor is uneven, and covered in hilly ripples. Aristoteles does possess central peaks, but they are somewhat offset to the south. 2005/09/22. C14 @ F41. LU075M.
Arzachel is a relatively young lunar impact crater located in the highlands in the south-central part of the Moon, close to the zero meridian. Together with Alphonsus and Ptolemaeus further north the three form a prominent trio of craters.
The rim of Arzachel shows little sign of wear and has a detailed terrace structure on the interior, especially on the slightly higher eastern rim. There is a rough outer rampart that joins a ridge running from the north rim to southern rim of Alphonsus crater.
The rugged central peak of Arzachel is prominent, rising 1.5 kilometers above the floor, and is somewhat offset to the west with a bowed curve from south to north-northeast. The floor is relatively flat, except for some irregularities in the southwestern quadrant of the crater. There is a rille system named the Rimae Arzachel that runs from the northern wall to the southeast rim. A small crater lies prominently in the floor to the east of the central peak, with a pair of smaller craterlets located nearby. 2006/04/08, 19 & 20. C14 @ F41. LU075M.
Atlas & Hercules.
Atlas is a prominent impact crater that is located in the northeast part of the Moon, to the southeast of Mare Frigoris. Just to the west is it forms a prominent pairing with the slightly smaller Hercules crater. The inner wall of the Atlas crater multiply terraced and the edge slumped, forming a sharp-edged lip.
This is a floor-fractured crater with a rough and hilly interior that has a lighter albedo than the surroundings. Floor-fractures are usually created as a result of volcanic modifications. There are two dark patches along the inner edge of the walls; one along the north edge and another besides the southeast edges. A system of slender clefts named the Rimae Atlas crosses the crater floor, and were created by volcanism. Along the north and northeastern inner sides are a handful of dark-halo craters, most likely formed due to eruptions. Around the mid-point is a cluster of low central hills arranged in a circular formation.
The interior walls of Hercules have multiple terraces, and there is a small outer rampart. The crater floor has been flooded by lava in the past, and contains several areas of low albedo. The central peak has been buried, leaving only a low hill near the mid-point. 2006/04/16. C14 @ F41. LU075M.
Autolycus is an impact crater that is located in the southeast part of Mare Imbrium. West of the formation is the Archimedes crater, a formation more than double the size of Autolycus. Just to the north is the Aristillus crater.
The rim of Autolycus is somewhat irregular, although generally circular overall. It has a small outer rampart and an irregular interior with no central peak. It possesses a light ray system that extends for a distance of over 400 kilometers. Some of the ray material appears to overlay the flooded floor of Archimedes crater. The Luna 2 probe crash-landed just to the west-southwest of the crater rim. 2006/04/19 & 2005/12/18. C14 @ F41. LU075M.
Bailly is a impact crater that is located near the south-west limb of the moon. The oblique viewing angle gives the crater a foreshortened appearance, and the location near the limb can limit visibility due to libration. The most favorable time for viewing this feature is near the full moon when the terminator is crossing the crater wall. This is the largest crater on the near side of the moon at 287km diameter, and by convention it is termed an impact basin. In area it is comparable in size to a small maria.
Bailly's uneven crater floor has remained free of lava flooding, and it is covered with a multitude of ridges and craters. The entire crater has been battered and worn, and the outer ramparts are eroded and in some places have even been worn away by myriad impacts. If the crater ever possessed a central peak, it is no longer discernable. Due to its current condition, observers have termed this feature a 'field of ruins'. Due to the size and the worn state of this crater, it is estimated to be more than 3 billion years old. 2006/04/12. C14 @ F41. LU075M.
Bettinus is an impact crater located near the southwest limb. Due to its location, the crater has a distinctly oval shape because of foreshortening. To the south of the rim is the similar-sized Kircher crater, and to the northwest is the slightly smaller Zucchius crater. From the west to the southwest, closer to the limb, is the giant Bailly crater.
The rim of Bettinus crater is only somewhat worn, with an inner wall that is wider to the northwest. The interior floor is relatively flat, with a central rise that is offset to the west of the mid-point. There is a small crater along the eastern rim. It is 71km diameter. 2006/04/11 & 21. 2006/11/04. C14 @ F41. LU075M.
Bianchini is a lunar crater that lies besides the northern Jura Mountains that ring the Sinus Iridum, in the northwestern part of the Moon. The impact of this crater near the edge of the Jura Mountains pushed some material into the Sinus Iridium floor. The rim of this crater is not significantly worn, although there is a small crater along the inner side of the eastern rim. Within the inner wall of Bianchini is a somewhat irregular floor and a small cluster of ridges at the mid-point. Portions of the inner wall have slumped toward the floor along the northern edges.
Biela is an impact crater that is located in the rugged highlands of the southeastern Moon. The crater lies to the southeast of the Watt-Steinheil double-crater. The rim of this crater is overlaid by a pair of small but notable craters: 'Biela C' across the northeast rim and 'Biela W' along the western inner wall. The satellite crater 'Biela B' is attached to the southwestern outer rim, and ejecta from Biela covers the northwestern part of the interior.
Despite a certain degree of wear, the rim of Biela crater remains relatively well-defined, especially in the southeast. The interior floor is flat and not marked by any craterlets of note. There is a central peak formation of three ridges located just to the northeast of the mid-point. 2006/11/06. C14 @ F41. LU075M.
Billy is an impact crater that is located at the southern fringes of the Oceanus Procellarum, in the western portion of the Moon. It lies to the southeast of the similar-sized Hansteen crater, and west-southwest of the flooded Letronne crater. The interior floor of Billy has been flooded by basaltic lava, leaving a dark surface due to the low albedo. The portion of the rim remaining above the surface is narrow and low, with a thin inner wall. Only a few tiny craterlets mark the interior.
To the north of the crater is a triangular mountainous formation named Mons Hansteen, from the nearby crater. Southeast of Billy crater is a rille, designated Rima Billy, that runs 70 kilometers to the south. Billy's appearance is very similar to the larger and more famous Plato crater. 2006/11/04. C14 @ F41. LU075M.
Blancanus is an impact crater located in the rugged southern region of the Moon, to the southwest of Clavius. The outer rim of Blancanus is considerably less worn than that of Scheiner crater to the northwest, and the edge is still fairly well defined and it has a terraced structure on the interior. The floor is relatively flat with several low rises at the mid-point. There is a cluster of small craterlets in the southern part of the crater floor. 2006/04/10. C14 @ F41. LU075M.
Boussingault is a large lunar crater that lies near the rugged southeast limb of the Moon. The most notable aspect of this crater is the large crater that lies entirely within its outer walls, so that it resembles a double-walled formation. The outer rim is worn and the 'Boussingault K' crater lies across the northwest rim. To the northwest is the overlapping triple crater formation of 'Boussingault E', 'B', and 'C'. 2007/03/26. C14 @ F41. SKYnyx 2.0M.
Bullialdus is an impact crater located in the western part of the Mare Imbrium. The relatively isolated location of this crater serves to highlight its well-formed shape. Bullialdus has a high outer rim that is circular but observers have noted a slightly polygonal appearance. The inner walls are terraced and contain many signs of landslips. The outer ramparts are covered in a wide ejecta blanket that highlights a radial pattern of low ridges and valleys.
In the center of the crater is a formation of several peaks and rises that climb to over a kilometer in height. A raised ridge runs from the peaks to the south-east, until finally merging with the inner wall. The floor of the crater is generally rough with many low rises. Overall it has a somewhat convex shape, bulging upward toward the middle. When the sun is at a high angle, the rim and central mountains appear brighter than the surroundings, and white patches can be viewed on the crater floor.
Infrared studies of the crater region have revealed at least three layers of strata. The impact may also have intersected a mafic pluton, which means a crystallized body of igneous rock that has high concentrations of heavier elements (such as Magnesium, in this case). 2006/04/09. C14 @ F41. LU075M.
Bürg is a prominent impact crater in the northeast part of the Moon. It lies within the lava-flooded, ruined crater formation designated Lacus Mortis. The rim of Bürg is nearly circular with relatively little wear. The interior is bowl-shaped, and there is a large central mountain at the mid-point. Along the crest of this mountain some observers have noted a small, crater-like pit. To the west is a rille system designated the Rimae Bürg, which spans a distance of about 100 kilometers. 2006/11/20. C14 @ F41. LU075M.
Capuanus is a lunar crater that lies along the southern edge of the Palus Epidemiarum. The outer rim is eroded and indented by lesser crater impacts, with notches in the north, west, and southern parts of the rim. The interior floor has been resurfaced by basaltic-lava, which is connected to the surrounding lunar mare by a narrow, crater-formed gap in the northern rim. The floor of Capuanus is particularly notable for the hosting a number of domes, which are believed to have formed through volcanic activity.
The rim achieves its maximum altitude along the western face, where it merges with ridges along the edge of the mare. To the northeast the rim dips down very close to the surface, and barely forms a curving ridge in the surface. The southeastern rim is overlaid by a pair of craters.
Carpenter is an impact crater that is located in the northern part of the Moon, relatively close to the limb. At this position the crater is forshortened and appears oval in shape. It is, however, very nearly circular in outline. The outer rampart to the south is adjoined to the old Anaximander crater, and the satellite formation 'Anaximander B' lies along the western rim. To the northeast is the Anaximenes crater.
In geological terms Carpenter is a somewhat young lunar crater, with features that have not been significantly eroded by subsequent impacts. Certainly it is much younger than the surrounding crater formations. The inner wall displays an appearance of slumping, particularly along the eastern face, and there is some development of terraces. The outer rim is unmarked by craterlets of note, but there is a small crater along the south-southeastern inner wall.
The interior floor within the slopping inner walls is generally level, but irregular with many small bumps and hills. Near the mid-point is an unusual double central peak formation, with a smaller peak offset to the west and a larger ridge offset to the east. The later ridge runs southward to the edge of the inner wall. 2006/04/21. C14 @ F41. LU075M.
Cassini is an impact crater that is located at the eastern end of Mare Imbrium. The floor of the crater is flooded, and is likely as old as the surrounding maria. The surface is peppered with a multitude of impacts, including a pair of significant craters contained entirely within the rim. Cassini A is the larger of these two, and it lies just north-east of the crater center. A hilly ridge area runs from this inner crater toward the south-east. Near the south-west rim of Cassini is the smaller crater Cassini B.
The walls of this crater are narrow and irregular in form but remain intact despite the lava flooding. Beyond the crater rim is a significant and irregular outer rampart. For unknown reasons, this crater was omitted from early maps of the Moon. This crater is not of recent origin, however, so the omission was most likely an error on the part of the map-makers. 2006/04/19 & 2005/09/22. C14 @ F41. LU075M.
Clavius is one of the largest crater formations on the Moon, and it is the third largest crater on the visible near side. It is located in the rugged southern highlands of the moon, to the south of the prominent Tycho crater.
Due to the location of the crater toward the southern limb, the crater appears oblong due to foreshortening. Because of its great size, Clavius can be detected with the unaided eye. It appears as a prominent notch in the terminator about 1-2 days after the Moon reaches first quarter. The crater is one of the older formations on the lunar surface and was likely formed during the Nectarian period about 4 billion years ago. Despite its age, however, the crater is relatively well-preserved. It has a relatively low outer wall in comparison to their size, and it is heavily worn and pock-marked by craterlets. The rim does not significantly overlook the surrounding terrain, making this a "walled depression". The inner surface of the rim is hilly, notched, and varies in width, with the steepest portion in the south end. Overall the rim has been observed to have a somewhat polygonal outline.
The floor of the crater forms a convex plain that is marked by some interesting crater impacts. The most notable of these is a curving chain of craters that begin with Rutherfurd in the south, then arc across the floor in a counterclockwise direction forming a sequence of ever diminishing diameters. From largest to smallest, these craters are designated Clavius D, C, N, J, and JA. This sequence of diminishing craters has proved a useful tool for amateur astronomers that want to test the resolution of their telescopes.
The crater floor retains a diminished remnant of a central massif, which lies between Clavius C and N. The relative smoothness of the floor and the low size of the central peaks may indicate that the crater surface was formed some time after the original impact
Notable nearby craters include Scheiner to the west; Blancanus to the southwest; Maginus in the northeast, and Longomontanus to the northwest. The Rutherfurd crater lies entirely within the southeastern rim, while Porter crater overlays the northeast wall. The smaller crater Clavius L lies across the western rim, and Clavius K breaks through the west-southwest rim. 2006/04/09, 19 & 20. 2006/11/04. 2005/11/20. C14 @ F41. LU075M.
Cleomedes is a prominent lunar crater located in the northeast part of the visible Moon, to the north of Mare Crisium. It is surrounded by rough ground with multiple crater impacts. The irregular Tralles crater is intruding into the northwest rim.
The outer wall of this crater is heavily worn and eroded, especially along the southern part of the wall. The 'Cleomedes C' crater lies across the south-southwest rim. The crater floor is nearly flat, with a small central peak to the north of the mid-point, forming a linear ridge toward the north-northeast. There are several notable craterlets on the floor, including a pair of overlapping craters just inside the northwest rim.
A rille named the Rima Cleomedes crosses the northern floor, running southeast from the northwest rim. This rille branches in a fork after crossing the crater mid-line. Smaller clefts lie in the southeast part of the floor. 2006/04/15 & 2006/11/06. C14 @ F41. LU075M.
Colombo is an impact crater that lies on the strip of rough continental terrain between Mare Fecunditatis to the east and Mare Nectaris in the west. The rim of Colombo is circular, although slightly indented along the northwest where 'Colombo A' intrudes slightly into the interior. The inner wall is asymmetrical, being much more narrow to the north and northwest and wider to the southeast. The rim is somewhat eroded, and several tiny craterlets lie along the inner wall to the southeast. The small satellite crater 'Colombo B' lies across the south-southwestern rim.
The interior floor of Colombo crater is nearly level, and has been partially covered by deposits of lava. This surface has a lower albedo than the surrounding surface, and has the same dark hue as the lunar mare to the east. At the mid-point of the interior is a semi-circular formation of four central ridges, resembling the remains of a larger mountain mass. 2006/04/16. C14 @ F41. LU075M.
Condorcet is a lunar crater that is located in the eastern part of the Moon's near side, to the southeast of the Mare Crisium. The outer rim of Condorcet crater is eroded, with a low saddle point along the northern wall and the satellite crater 'Condorcet Y' lays across the northwestern rim. The interior floor has been resurfaced, leaving a level, nearly featureless surface that is marked only by a few tiny craterlets. The floor has a large dark patch in the western half, but the remainder is approximately the same albedo as the surrounding terrain. 2006/04/14. C14 @ F41. LU075M.
Copernicus is a prominent impact crater located on the eastern Oceanus Procellarum. The crater Copernicus is estimated to be about 800 million years old, the time marking the start of the Copernican era in the Lunar geologic timescale. Due to its relative youth, the crater has received very little erosion and it remains sharp and well-defined.
The circular rim has a discernable hexagonal form, with a terraced inner wall and a 30-km wide, sloping rampart that descends nearly a kilometer to the surrounding maria. There are three distinct terraces visible, and arc-shaped landslides due to slumping of the inner wall as the crater debris subsided.
Most likely due to its recent formation, the crater floor has not been flooded by lava. The terrain along the bottom is hilly in the southern half while the north is relatively smooth. The central peaks consist of three isolated mountainous rises climbing as high as 1.2 km above the floor. These peaks are separated from each other by valleys, and they form a rough line along an east-west axis. Infrared observations of these peaks during the 1980s determined that they were primarily composed of the mafic form of Olivine.
The crater rays from Copernicus spread as far as 800 kilometers across the surrounding maria, overlaying rays from the Aristarchus and Kepler craters. The rays are less distinct than the long, linear rays about Tycho crater, instead forming a nebulous pattern with plumy markings. In multiple locations the rays lay at glancing angles, instead of forming a true radial dispersal. An extensive pattern of smaller secondary craters can also be observed surrounding Copernicus, a detail that was depicted in a map by Giovanni Cassini in 1680. Some of these secondary craters form sinuous chains in the ejecta. 2006/04/09 & 20. C14 @ F41. LU075M.
Curtius is a impact crater that is located in the southern part of the Moon. Curtius is located within one-crater diameter of the still-larger Moretus crater to the southwest. The outer rim of Curtius has been softened due to impact erosion, but it retains much of its original structure. Along the north and northwest parts of the rim are a pair of notable outward bulges that ruin the overall symmetry of the crater. There is a small satellite crater 'Curtius E' lying across the eastern rim, and a small, bowl-shaped craterlet 'Curtius A' along the southern rim.
The interior floor is relatively level, with a low, rounded central peaks near the mid-point. The northern part of the inner wall has extended further into the crater floor than elsewehere, producing a slightly irregular surface. The floor is covered by a number of tiny craterlets, but there are no other impacts of note across the interior. 2005/11/20. C14 @ F41. LU075M.
Darwin Rimae. Parts of the interior floor of Darwin crater have been resurfaced, possibly by lava or fall-back ejecta, and a system of rilles cut across the northern part of the floor, crossing the eastern rim and continuing to the southeast. These rilles stretch for a distance of about 280 kilometers. To the east of Darwin, this system of rilles crosses Rima Sirsalis, a wide rille that follows a line to the northeast. 2006/04/12. C14 @ F41. LU075M.
Davy & Catena Davy. Davy is a small lunar crater that is located on the eastern edge of the Mare Nubium. It is overlaying the lava-flooded remains of the satellite crater 'Davy Y' to the east, a formation which contains a crater chain designated Catena Davy.
The outer rim of Davy is low, and the interior has been partly resurfaced. The perimeter is somewhat polygonal in shape, especially in the western half, and the southeast rim has been overlain by the 'Davy A' crater. The later is bowl-shaped with a notch in the northern rim. The interior of Davy lacks a central peak, although there are some low central mounds and the rim of 'Davy Y' forms a low ridge leading from the northern outer rim.
Catena Davy is a string of 23 tiny craters that runs from the mid-point of 'Davy Y' toward Ptolemaeus, following a slightly curving course to the east-northeast. It has a diameter of 50 km.
Catena Davy is not believed to be due to secondary cratering because it is not radial to a suitable source crater. The most likely cause is believed to be due to a single body that broke apart prior to impact due to tidal effects. High resolution images have demonstrated that the craters formed at about the same time since the ejecta from each crater does not overlay neighboring craters. However there are still some scientists who believe that this chain of craters may be volcanic in origin. 2006/04/19. C14 @ F41. LU075M.
Delambre is a lunar impact crater that lies to the southwest of Mare Tranquillitatis, in the central highland region. To the west are the crater pair of Theon Junior and Theon Senior, the later being more distant and located to the northwest. The rim of Delambre has a terraced interior, with a tiny craterlet lying along the northern rim. In the south is a low cut forming a slight notch. The crater interior has an irregular surface. 2007/03/27. C14 @ F42. SKYnyx 2.0M.
Demonax is a lunar impact crater near the southern limb of the Moon. This location makes the crater difficult to observe due to foreshortening. The crater is also illuminated at a very low angle, when it is in the sunlit side. Demonax lies just to the north of Scott crater, one of the south polar formations.
This crater has a worn and eroded rim, with several small craters lying along the edge and the inner walls. The southeast rim in particular has a notable collection of impacts, including the satellite crater 'Demonax A' which intrudes into the interior floor. The crater bottom has been resurfaced, leaving a flat, level floor. However there is a group of central peaks near the mid-point, and the northern part of the floor is rough and hummocky. The remains of some terraces are visible along the western interior floor.
Due to the low angle of sunlight reaching this crater, the inner wall along the north side of the crater receives very little sunlight. 2007/03/26. C14 @ F42. SKYnyx 2.0M.
Deslandres is the heavily worn and distorted remains of a lunar impact crater. It is located to the southeast of the Mare Nubium, in the rugged southern highlands of the moon. In dimension it is the second-largest crater formation on the visible moon at 234km diameter, being exceeded only by the 303km diameter Bailly crater. The northern and eastern parts of the floor display a relatively level surface, but it is pock-marked with numerous craters. There is a small region of mare material, due to basaltic lava, along the eastern interior floor.
The Walther crater is attached to the remnant of the eastern rim, and Ball crater intrudes into the southwestern rim. The crater remnant Lexell crater has broken across the southeastern rim, forming a "harbor" in the crater floor due to the wide gap in its northern rim. The irregular Regiomontanus crater is attached to the northeast rim of Deslanders. Hell crater lies entirely within the western rim.
The satellite crater 'Hell Q' lies at the center of a patch of higher albedo surface located in the eastern half of Deslandres. Around the time of the full moon this feature is one of the brightest spots on the lunar surface. The light hue indicates a relatively youthful feature in lunar geologic terms. This patch is sometimes referred to as "Cassini's bright spot", as it had first been mapped by Cassini in 1672 at the Paris Observatory.
This feature is so heavily eroded and degraded by overlapping impacts that it wasn't actually recognized as a crater formation until the 20th century. The name for this formation was suggested by Eugène M. Antoniadi in 1942, and was passed during the first general assembly of the IAU in 1948. 2006/10/14. C14 @ primefocus. SKYnyx 2.0M.
Doppelmayer is the remains of a lunar crater that lies on the southwest edge of Mare Humorum. To the south-southeast is another flooded crater designated Lee. Just to the east-northeast of the Doppelmayer crater rim lies the nearly submerged Puiseux crater. The rim of Doppelmayer is nearly round, but is worn and eroded. The most intact section is the southwest half, while in the northeast the rim descends beneath the mare, leaving only a slight rise in the surface. The interior has been flooded by lava, leaving a large raised ridge in the center. A small range of hills curves to the west and north from the southern end of this ridge, forming a feature that is nearly concentric with the crater's outer rim. 2006/04/10. C14 @ F41. LU075M.
Einstein is a large lunar crater that lies along the western limb of the Moon, making it difficult to observe from the Earth. The visibility of this formation is affected by libration effects, but even under the best conditions not much detail can be observed except from lunar orbit. Nearby craters of note include Moseley just to the north, Dalton along the eastern rim, Vasco da Gama just to the southeast, and Bohr crater to the south-southeast. The formation Vallis Bohr is visible to the south.
The outer rim of this walled plain has been all but obliterated by many small impacts. Only along the eastern wall, where it joins Dalton crater, does a significant rim still survive. Occupying the center of the interior floor is 'Einstein A', an impact crater with terraced inner walls and a central peak. The outer rampart of this concentric crater spreads across the interior floor, covering over half the diameter of the Einstein crater. Several smaller craters also lie scattered across the floor, but there are sections of relatively flat surface in the southwest part of the floor.
Because it is only visible under very favorable conditions, this crater was only discovered as recently as 1952 by Patrick Moore. The original name for this formation was "Caramuel", but it was later changed to Einstein by the IAU. April 2005. C9.25 @ F42. LU075M.
Endymion is a lunar crater that lies near the northeast limb of the Moon. It is located to the east of the Mare Frigoris. Because of its location, the Endymion crater has an oval appearance from foreshortening. Beyond the crater along the lunar limb is the Mare Humboldtianum.
The floor of Endymion has been covered in low albedo lava, that gives it a dark appearance and makes it relatively easy to locate. The floor is nearly smooth and featureless, with only a few tiny craterlets located within the rim. A string of three lie near the northwestern inner wall. Faint streaks of ray material from Thales crater to the north-northwest crosses the dark floor. The outer rampart is low, wide, and worn from impact erosion. 2006/04/15. C14 @ F41. LU075M.
Endymion B & Hayn A. These two rarely photographed craters lie some way north of Endymion itself, and are both around 60km diameter. Note the interesting "layered" mountain behind which is part of the inner ring of mountains of Mare Humboldtianum. This area can only be well seen during favourable northern librations, since Humboldtianum extends over to the far side of the Moon. 2006/04/14. C14 @ F41. LU075M.
Eratosthenes is a relatively deep lunar impact crater that lies on the boundary between the Mare Imbrium and Sinus Aestuum maria regions. The crater has a well-defined circular rim, terraced inner wall, central mountain peaks, an irregular floor, and an outer rampart of ejecta. It lacks a ray system of its own, but is overlaid by rays from the Copernicus crater to the south-west. The Eratosthenian period in the lunar geologic timescale is named after this crater. The crater is believed to have been formed about 3.2 billion years ago, defining the start of this time period.
At low sun-angles this crater is prominent due to the shadow cast by the rim. When the sun is directly overhead, however, Eratosthenes visually blends into the surroundings, and it becomes more difficult for an observer to locate it. The rays from the Copernicus crater lie across this area, and the higher albedo of these rays serves as a form of camouflage.
In 1924, William H. Pickering noted dark patches in the crater that varied in a regular manner over each lunar day. He put forward the speculative idea that these patches appeared to migrate across the surface, suggestive of herds of small life forms. The idea received a degree of attention primarily due to Pickering's reputation. 2006/04/20 & 2006/10/13. C14 @ F41. LU075M.
Eudoxus is a prominent impact crater that lies to the east of the northern tip of the Montes Caucasus range. It is located to the south of the prominent Aristoteles crater in the northern regions of the visible Moon. The rim of Eudoxus has a series of terraces on the interior wall, and slightly worn ramparts about the exterior. It lacks a single central peak, but has a cluster of low hills about the mid-point of the floor. The remainder of the interior floor is relatively level. 2006/04/18 & 2005/11/20. C14 @ F41. LU075M.
Fra Mauro is the worn remnant of a walled lunar plain. It is part of the surrounding Fra Mauro formation, being located to the northeast of Mare Cognitum and southeast of Mare Insularum. Attached to the southern rim are the co-joined Bonpland and Parry craters, which intrude into the formation forming inward-bulging walls.
The surviving rim of Fra Mauro is heavily worn, with incisions from past impacts and openings in the north and east walls. The rim is the most prominent in the southeast, where it shares a wall with Parry. The remainder consists of little more than low, irregular ridges. The maximum elevation of the outer rim is 0.7 km. The floor of this formation has been covered by basaltic-lava. This surface is almost divided by clefts running from the north and south rims. There is no central peak, although the tiny 'Fra Mauro E' crater lies at almost the mid-point of the formation.
Just to the north of the walled plain is the landing site of the Apollo 14 mission. The crew sampled breccia that had been deposited here by the Imbrium basin-forming impact, and which partly covers the Fra Mauro crater. This rough debris blanket of ejecta is referred to as the "Fra Mauro Formation". The doomed Apollo 13 mission was also scheduled to land here. 2006/04/21. C14 @ f41. LU075M.
Franklin is a lunar impact crater that is located in the northeast part of the visible Moon. To the north-northwest is the smaller Cepheus crater, and in the opposite direction to the southwest is the shallow Berzelius crater. The rim of Franklin is generally circular, with a pair of outward bulges in the western wall. The inner wall is terraced, and there is a central peak at the mid-point of the floor. A narrow cleft runs to the west-southwest across the floor, passing to the north of the central peak. 2005/12/20 & 2006/04/16. C14 @ F41. LU075M.
Gassendi is a large lunar crater feature located at the northern edge of Mare Humorum. The formation has been inundated by lava during the formation of the mare, so only the rim and the multiple central peaks remain above the surface. The outer rim is worn and eroded, although it retains a generally circular form. A smaller crater 'Gassendi A' is intruding into the northern rim, and joins a rough uplift at the northwest part of the floor. The crater pair bears a curious resemblance to a diamond ring.
In the southern part of the crater floor is a semi-circular ridge-like formation that is concentric with the outer rim. It is in the southern part where the rim dips down to its lowest portion, and a gap appears at the most southern point. The rim varies in height from as little as 200 meters to as high as 2.5 kilometers above the surface. The floor has numerous hummocks and rough spots. There is also a system of rilles that criss-cross the floor, named the Rimae Gassendi. 2006/04/10. C14 @ F41. LU075M.
Gauss, Hahn & Berosus. Gauss is a large lunar crater that is located near the northeastern limb of the Moon's near side. It belongs to a category of lunar formations called a walled-plain, meaning that it has a diameter of at least 110 kilometers, with a somewhat sunken floor and little or no central massif. Due to its location, this crater appears considerably foreshortened when viewed from the Earth, and its visibility is affected by libration. Southwest of Gauss is the crater pair of Hahn and Berosus which are seen in this image. The rim of Gauss crater is better formed in the northern half, and the inner walls have some terracing along the northwest and appear slumped in the northeast. The southern half of the rim is somewhat more eroded.
The interior floor is fairly flat in places, with several craters marking the surface in the southern half. There is also a small crater 'Gauss B' lying along the interior of the eastern rim, with the smaller 'Gauss A' lying across the rim just to the northeast of 'Gauss B'. The floor of Gauss is also marked by several clefts, particularly along the eastern and northwestern edges. The uneven crater rims in the south and a series of rises in the north gives the appearance of a ridge line that traverses the crater floor from north to south.
Hahn's inner wall contains a system of terraces, particularly in the southern half. A smaller crater lies across the northwest rim, forming a break that reaches the interior floor. The interior floor has a region of lower albedo in the northern half, making it darker in appearance than the southern section of the floor. At the mid-point of the interior is an elongated central ridge, with the longer extent oriented north-south. The floor is also marked by several tiny craterlets.
Berosus is roughly circular, but with some angularity along the eastern edge. The southern end of the crater has been heavily eroded, and there are some tiny craterlets along the northern rim. The inner walls have some terracing along the east and northwestern sides. The interior floor of Berosus crater has been flooded by lava, and so is level and nearly featureless. 2006/04/14. C14 @ F41. LU075M.
Hadley Rima is a famous sinuous rille which lies close to the Montes Apenninus and is most famous for Apollo 15 landing there duing the 1970s. It is thought to be the remains of a collapsed lava tube. It is approximately 1.5km wide, and between 0.3 - 0.7km deep. Nearby Mons Hadley towers more than 5km above the lunar surface. It was very close to the northern "curve" of the rille (near the top in these images) that Apollo 15 landed on July 30th, 1971. 2006/04/19, 2005/12/20, 2005/09/22 & 2007/03/26. C14 @ F41. LU075M.
Hainzel is the southern member of a trio of overlapping craters. The composite rim is located at the west edge of Lacus Timoris in the southwest sector of the Moon. The heavily worn Mee crater is attached to the southwest wall; its rim forming a ridge running from the south of the Hainzel.
The Hainzel crater forms the south portion of the grouping, and is overlain by 'Hainzel C' to the northeast, and then by 'Hainzel A' in the north. 'Hainzel A' is the most intact and also the youngest of the cluster. The wall between Hainzel and 'Hainzel C' is the most intact of the interior rims, forming a promontory from the southeast wall. Both 'Hainzel A' and C have central peaks. 2006/04/21. C14 @ F41. LU075M.
Hansteen is a lunar crater that lies near the southwest edge of the Oceanus Procellarum. The rim of Hansteen is somewhat polygonal in form, especially along the eastern side. There are a few terraces along the northwestern inner wall. The inner floor contains several ridges, hills, and some grooves, many of which parallel the outer rim. There is a flat patch of lower-albedo material in the northeast part of the interior.
Paralleling the southwest outer wall is the brief rille designated Rima Hansteen, a formation with a length of about 25 kilometers. To the southeast of the crater rises the Mons Hansteen mount, or Hansteen Alpha. This is roughly triangular in shape and occupies an area about 30 km across on the mare. This feature is younger than Hansteen crater and is thought to be an extrusion of volcanic material. 2006/11/04. C14 @ F41. LU075M.
Harpalus is a young impact crater that lies on the Mare Frigoris, at the eastern edge of the Sinus Roris. The rim of Harpalus is sharp-edged with little sign of wear or erosion. It is surrounded by an outer rampart of ejecta, most notably toward the north, and is at the center of a small ray system. The wall is not perfectly circular, and has a few outward notches and protrusions, especially along the eastern half.
The inner surface is terraced, and flows down to the floor. The interior wall is the least wide along the northern face, making the floor slightly offset in that direction. Near the mid-point is a system of low central ridges.
This was the crater chosen as a rocket landing site in the 1950s science fiction film Destination Moon. It was chosen by the artist Chesley Bonestell as it had a relatively high latitude and the Earth could be realistically displayed at a low altitude during camera shots. However, the resulting clay model of the crater was given some mud cracks across the floor, an addition to which Bonestall objected. 2006/11/04. C14 @ F41. LU075M.
Heraclitus is a complex lunar crater that lies in the rugged southern highlands of the Moon. Licetus crater forms the northern end of the formation. Just to the east is Cuvier crater, and due south is Lilius crater.
The entire formation is heavily worn, with features smoothed down by a long history of impacts. Heraclitus is a complex formation composed of three sections divided by a triple-armed interior ridge. Of the three sections, the most eroded and irregular is at the eastern end where the outer rim forms a low ridge that joins to Cuvier crater.
The circular southwest end is the most intact section, forming the circular satellite crater 'Heraclitus D', which is attached to the other two sections along the northeast rim. There are a pair of ghost-crater rims on the floor, and a low ridge in the southwest. Just to the west of Heraclitus is the small satellite crater 'Heraclitus K', to the south of which is a pair of larger overlapping craters, 'Lilius E' and Lilius D'. 2006/04/19. C14 @ F41. LU075M.
Hermite is a lunar impact crater located along the northern lunar limb, close to the north pole of the Moon. It was first discovered in 1964. To the west is the Rozhdestvenskiy crater, and to the south are the Lovelace and Sylvester craters. From the Earth Hermite is viewed nearly from the side, and it is illuminated by oblique sunlight. It lies at 86N and 90W, meaning it is only visible during excellent north western librations of the Moon.
This is a worn, eroded crater with a rugged outer rim that is notched and incised from past impacts. A crater overlays the southwestern rim, and the two formations have merged to share a common interior floor. A pair of small craters lie along the southern part of the rim, and a small crater is also attached near the northern end. The interior floor has been resurfaced, so that it forms a wide plain that is pock-marked by numerous tiny craterlets and low hills. There is a small crater on the floor near the northeastern wall. 2006/04/19. C14 @ F41. LU075M.
Herschel is an impact crater located just to the north of Ptolemaeus crater. The rim of this crater is generally circular, although the western side is straight. It has a well-defined edge that is not significantly worn, and the inner walls are terraced. On the rough inner floor is a notable central rise. This peak is offset slightly to the west of the crater mid-point. The small crater 'Herschel G' is attached to the south-southwest rim, and a tiny craterlet lies across the southern rim. 2006/04/19 & 2005/12/10. C14 @ F41. LU075M.
Hevelius is a low-rimmed lunar crater that lies at the western edge of the Oceanus Procellarum. The smaller but prominent crater Cavalerius is joined to the northern rim by low ridges.
Only a low, eroded rim of Hevelius rises above the surface. The western wall is overlain by several small impacts. The flat floor of the crater has been flooded by lava, and is now cross-crossed by a system of small clefts named the Rimae Hevelius. There is a low, 1 km-high central peak offset to the northwest of the mid-point. The northeastern part of the interior is more irregular and contains a straight ridge running toward the southeast. Along the northwest floor, near the inner wall, is a small crater. 2006/04/12. C14 @ F41. LU075M.
Hippalus the remnant of a lunar crater on the eastern edge of Mare Humorum. The southwest rim of the crater is missing, and the crater forms a bay along the edge of the mare. The surviving rim is worn and eroded, forming a low, circular mountain range. The lava-flooded floor of Hippalus is bisected by a wide rille belonging to the Rimae Hippalus. This rille follows a course to the south before curving gently to the southwest for a total length of 240 kilometers. The crater floor to the east of this rille is more rugged than the area in the western half. 2006/04/10. C14 @ F41. LU075M.
Hipparchus is the degraded remnant of a lunar crater. It is located to the southeast of Sinus Medii, near the center of the visible Moon. The Horrocks crater lies entirely within the northeast rim of the crater. Halley crater is attached to the south rim, and Hind crater lies to the southeast. To the north-northeast is the bowl-shaped Pickering crater, and the flooded Saunder crater is located off the northeast rim.
This feature is an ancient crater that has been subject to considerable modification due to subsequent impacts. The western rim of Hipparchus has been all but worn away from impact erosion, and only low hills and rises in the surface remain to outline the feature. The wall to the east is somewhat more intact, but it too is heavily worn. A pair of deep clefts lie in the western wall. These parallel a sets of scars running through the south-central highlands.
The crater floor has been partially resurfaced by basaltic lava flow. The southwest part of the floor, however, is slightly raised and much more rugged than the remainder. A few small rises and the raised partial rim of a flooded crater are all that remain of a central massif.
Gaps in the northwest rim of Hipparchus crater rim form valleys that connect with the maria to the northwest. A rille named Rima Réaumur runs from this site to the outer wall of Réaumur 2006/10/13. C14 @ primefocus. SKYnyx 2.0M.
Humboldt is a large lunar crater that is located near the eastern limb of the Moon. Due to foreshortening this formation has an extremely oblong appearance. The actual shape of the crater is an irregular circle, with a significant indentation along the southeastern rim where the prominent Barnard crater intrudes. To the north-northwest of Humboldt is the large Hecataeus crater. Phillips is attached to the western rim.
The rim of the Humboldt is low, worn, and irregular in outline. The central peak forms a range on the crater floor. The floor surface contains a network of clefts forming a pattern of radial spokes and concentric arcs. There are also some dark patches located near the walls to the northeast, northwest, and southeast. There is a chain of craters leading from the northwest crater rim to a distance almost as long as the crater is wide. This formation has the designation Catena Humboldt.
Due to its location near the limb, little detail was known about this crater until it was photographed by orbiting spacecraft. 2006/11/05. C14 @ F25. SKYnyx 2.0M.
Hyginus is a small lunar caldera located at the east end of the Sinus Medii. The crater rim is split by a long, linear rille that branches to the northwest and to the east-southeast for a total length of 220 km. The crater is deeper than the rille, and lies at the bend where they intersect. Together the Hyginus crater and Rima Hyginus form a distinctive and prominent feature in an otherwise flat surface. Smaller craterlets can also be discerned along the length of this rille, possibly caused by a collapse of an underlying structure.
This is one of the few craters on the Moon that was not created as a result of an impact, and is instead believed to be volcanic in origin. It lacks the raised outer rim that is typical with impact craters. 2006/04/19. C14 @ F41. LU075M.
Inghirami is a lunar impact crater that is located toward the southwestern limb of the Moon. It lies to the southwest of the large Schickard walled plain. Northwest of Inghirami crater is the wide Vallis Inghirmi, a wide, straight valley that is radial to the Mare Orientale impact basin. It has a length of about 140 kilometers and ends at the northern edge of the crater.
This crater is located near the southeastern edge of the immense skirt of ejecta that surrounds the Mare Orientale. This material has formed linear ridges and valleys that continue across most of the crater rim and interior from the northwestern face. Much of the outer rim has been modified by this impact material, and the most intact part of the rim lies along the southeast edge.
The partly-buried rim of this crater is roughly circular and somewhat irregular. There are some shelves and terraces along the sides, but these features are moderately eroded. A few small craters lie along or near the rim. The most notable crater on the interior floor is a small impact beside the eastern inner wall. The interior floor retains its ridges, streaky appearance across much of the crater, with only an area by the eastern rim being relatively flat and featureless. 2006/04/12. C14 @ F41. LU075M.
J. Herschel is large lunar crater of the variety termed a walled-plain. It is located in the northern part of the Moon's surface, and so appears foreshortened when viewed from the Earth. The southeastern rim of J. Hershel forms part of the edge of the Mare Frigoris lunar mare.
The rim of J. Herschel crater has been heavily eroded, to the point where it is frequently described as "considerably disintegrated". The remaining rim survives as a ring of ridges that have been resculpted by subsequent impacts. The interior floor is relatively level, but irregular and marked by a multitude of tiny impacts. The most notable of these are the satellite craters C, D, K, and L, listed in the table below. 'Horrebow A' is attached to the southern rim of the crater, and is overlapped along its southwest rim by Horrebow. April 2005. C9.25 @ F42. LU075M.
Janssen is an ancient impact crater located in the highland region near the southeastern lunar limb. The entire structure has been heavily worn and is marked by many lesser crater impacts. The outer wall is breached in multiple locations, but the outline of the crater rim can still be observed. The wall forms a distinctive hexagonal shape upon the rugged lunar surface, with a slight curvature at the vertices.
The prominent Fabricius crater lies entirely within the outer wall, in the northeast quadrant of the floor. A number of other lesser, but still notable craters mark the crater floor. Connected to the northeast rim is the Metius crater, and to the north is the heavily worn Brenner crater. Astride the southwest wall is the smaller Lockyer crater.
In the south two-thirds of the Janssen can be discerned the remains of a large, concentric crater, the wall of which is overlaid by Fabricus. The floor of this inner depression contains a rille system named the Rimae Janssen. The rille curves from the rim of Fabricius crater to the southeast of the Janssen outer wall, extending for a distance of up to 140 kilometers. 2006/04/15 & 16. 2006/11/06. C14 @ F41. LU075M.
Kepler is a young lunar impact crater that lies between the Oceanus Procellarum to the west and Mare Insularum in the east. Kepler is most notable for the prominent ray system that covers the surrounding maria. The rays extend for well over 300 kilometers, overlapping the rays from other craters. Kepler has a small rampart of ejecta surrounding the exterior of its high rim. The outer wall is not quite circular, and possesses a slightly polygonal form. The interior walls of Kepler are slumped and slightly terraced, descending to an uneven floor and a minor central rise.
One of the rays from Tycho crater, when extended across the Oceanus Procellarum, intersects this crater. This was a factor in the choice of the crater's name when Giovanni Riccioli was creating his system of lunar nomenclature, as Kepler used the observations of Tycho Brahe while devising his three laws of planetary motion. On Riccioli's maps, this crater was named Keplerus, and the surrounding skirt of higher albedo terrain was named Insulara Ventorum. 2006/02/09 & 2006/02/10. C14 @ primefocus & F41. LU075M.
Kies is the remnant of a lunar crater that has been flooded by basaltic-lava, leaving only a remnant of the outer rim. It is located in the Mare Nubium almost due south of Bullialdus. To the south-southwest lies a lunar dome structure designated Kies Pi (π). It has a small crater at the top, and is most likely volcanic in origin.
The rim of Kies crater has numerous gaps, and forms a series of ridges in a ring-shaped formation. The most intact rim structures lie in the south and northeast sections of the wall. A low promontory ridge is attached to the southern end of the rim, pointing southward. 2006/04/08. C14 @ F41. LU075M.
Kircher is located in the southwestern part of the Moon, near the southern limb. In this position the crater appears foreshortened when viewed from the Earth. It lies than one crater diameter due south of Bettinus crater, and is nearly attached to Wilson crater along the south-southeast rim of Kircher.
This crater is distinctive for an interior floor that is level and nearly featureless. It is marked only by a few tiny craterlets, with a single small craterlet near the north-northeast inner wall. The rim and inner wall has been worn and rounded by impacts, although only a few tint craters lie across the rim. Attached to the outside of the western rim is a crater pair, with the larger of the two designated 'Kircher D'. A small, cup-shaped crater lies on the narrow neck of ground between Kircher and Wilson crater. 2006/04/11 & 12. C14 @ F41. LU075M.
Klaproth & Casatus. Klaproth is an old lunar crater that lies in the rugged southern highlands of the Moon's near side. Due to its location, this crater appears significantly foreshortened. The southern rim of the crater is overlaid by the similar-sized Casatus crater
The outer rim of Klaproth has been deeply eroded, incised, and reshaped by a long history of bombardment. The rim to the north and east remains relatively circular, but the original rim along the western face has been overlain by satellite craters 'Klaproth G' and 'Klaproth H', and other impacts. To the south the crater Casatus significantly intrudes into the interior floor. The remaining floor has been resurfaced by some material in the past, possibly fluidized ejecta or lava, leaving a level and nearly featureless surface that is marked only by a multitude of tiny craterlets. If this walled-plain once possessed a central peak, it no longer exists.
The outer rim of Casatus is old and worn, with many tiny impacts along the rim and inner wall. The small satellite crater 'Casatus J' lies across the south-southeastern rim. The height of the rim is lower where it divides this crater from Klaproth, forming a rounded ridge. The interior floor is a nearly level surface marked by several tiny ghost-crater rims projecting above the surface and a pair of clefts in the southern part of the floor. A small, bowl-shaped impact crater forms a prominent feature in the northern half of the floor. There is no central peak formation at or near the mid-point of the interior. 2006/04/10 & 11. C14 @ F41. LU075M.
Lambert is a lunar impact crater on the southern half of the Mare Imbrium basin. Lambert is relatively easy to locate due to its isolated position on the mare. It has an outer rampart, terraced inner walls, and a rough interior that has a comparable albedo to its surroundings. Instead of a central peak, a small craterlet lies at the mid-point of the interior. 2006/04/09. C14 @ F41. LU075M.
Langrenus is a prominent impact crater located near the eastern lunar limb. The feature is circular in shape, but appears oblong due to foreshortening. It lies on the eastern shore of the Mare Fecunditatis. The inner wall of Langrenus is wide and irregularly terraced, with an average width of about 20 km. The outer ramparts are irregular and hilly, and there is a bright, fragmented ray system spread across the maria to the west. The interior of the crater has a higher albedo than the surroundings, so the crater stands out prominently when the sun is overhead. The crater floor is covered by many boulders, and is slightly irregular in the northwest half. The central peaks rise about a kilometer above the floor, and a peak on the eastern rim ascends to an altitude of 3 km.
During the Apollo 8 mission, Astronaut James Lovell described Langrenus as, "quite a huge crater; it's got a central cone to it. The walls of the crater are terraced, about six or seven terraces on the way down."
In the past this crater has not been noted as a site for observing transient lunar phenomenon. However on December 30, 1992, Audouin Dollfus of the Observatoire de Paris observed a series of glows on the floor of this crater using the one-meter telescope. These glows changed form with time, and Professor Dollfus expressed the belief that this was likely a gaseous emission. The cracked floor of the crater may have been the source of the gas.
The Flemish Astronomer Michel Florent van Langren was the first person to draw a lunar map while giving names to many of the features. He even named this crater after himself. Ironically, this is the only one of his named features that has retained his original designation. 2006/11/06. C14 @ F41. SKYnyx 2.0M.
La Pérouse & Ansgarius. La Perouse is an impact crater that is located near the eastern limb of the Moon. It lies northwest of the larger Ansgarius crater, and to the east of Kapteyn crater. This crater appears foreshortened due to its location, but the rim is nearly circular when viewed from orbit.
The rim of La Pérouse is not significantly worn by subsequent impacts, and its features are well-defined. terraces line much of the inner wall, and there is a small outer rampart. There are also small outward bulges in the rim to the south-southeast and south-southwest. Within the interior floor is a central ridge ofset to the northeast of the mid-point, and this formation is somewhat elogated to the southeast. There is a small crater in the southeastern part of the floor.
Ansgarius is not significantly worn, and has a terraced interior surface. The southwest rim appears somewhat flattened rather than round, and intrudes into an older formation of which little remains except the western rim. There is an outward notch in the north-northeastern wall. The interior floor of Ansgarius is relatively flat, with only tiny craterlets to mark the surface. 2006/11/05. C14 @ F41. LU075M.
Longomontanus is an ancient impact crater located in the rugged southern highlands to the southwest of Tycho. It is of the variety of large lunar formations sometimes called a "walled plain", although it is actually more of a circular depression in the surface. Because of its location, the Longomontanus appears distinctly oval in shape due to foreshortening.
The wall of Longomontanus is heavily worn and incised by past impacts, and the rim is essentially level with the surrounding terrain. The northern rim especially is impacted with multiple overlapping craterlets. To the east of the rim is a semi-circular ridge that has the appearance of an overlapped crater rim. The crater floor of Longomontanus is relatively flat, with a low cluster of central peaks somewhat offset to the west. 2006/04/09 & 19. C14 @ F41. LU075M.
Lyot is a large lunar crater that is located along the southeastern limb of the Moon. It lies within the irregular and patchy lunar mare named Mare Australe. Due to its location, this formation is viewed at a low angle from the Earth, and visibility is affected by libration. The interior floor of this crater has been resurfaced by lava, leaving a dark interior with an albedo that matches the surrounding mare. The outer rim of Lyot is low and heavily worn, with a perimeter that forms a somewhat distorted circle. The southwest part of the floor and rim is marked by several small, bowl-shaped craters. There is also the remains of a ghost-crater to the east of the crater mid-point. 2006/11/05. C14 @ F25. SKYnyx 2.0M.
Macrobius is a prominent impact crater located to the northwest of the Mare Crisium. The outer wall of Macrobius has a multiply-terraced inner surface, with some slumping along the top of the rim. The small satellite crater 'Macrobius C' lies across the western rim, but the wall is otherwise relatively free of significant wear. In the center of the floor is a central mountain complex. There is a low ridge in the western interior, but the remainder of the floor is relatively level. 2006/04/16. C14 @ F41. LU075M.
Maginus is an ancient lunar impact crater located in the southern highlands to the southeast of the prominent Tycho crater. It is a large formation almost three quarters the diameter of Clavius, which lies to the southwest. Just to the north of Maginus is the smaller Proctor crater.
The rim of Maginus crater is heavily eroded, with impact-formed incisions, and multiple overlapping craters across the eastern side. The wall is broken through in the southeast by 'Maginus C', a worn crater. Little remains of the original features that formed the rim of Maginus, and it no longer possesses an outer rampart. The floor is relatively flat, with a pair of low central peaks. 2006/04/19. C14 @ F41. LU075M.
Mairan is an impact crater that is located on a highland peninsula between Oceanus Procellarum to the west and Mare Imbrium to the east. The outer rim of Mairan has not been significantly eroded or impacted, and retains a sharp edge. The surface about Mairan is rough and irregular, with a multitude of many tiny craters, particularly to the south and west. The inner walls display some terracing, and flow down to a relatively flat interior floor. 2006/04/21 & 2006/11/04. C14 @ F41. LU075M.
Manilius is a lunar impact crater on the northeast edge of Mare Vaporum. It has a well-defined rim with a sloping inner surface that run directly down to the ring-shaped mound of scree along the base, and a small outer rampart. The small crater interior has a higher albedo than the surroundings, and it appears bright when the sun is overhead. Within the crater is a central peak formation near the mid-point. Manilius also possesses a ray system that extends for a distance of over 300 kilometers. 2007/03/27. C14 @ F42. SKYnyx 2.0M.
Manzinus & Mutus. Manzinus is located in the southern region of the Moon's near side. It lies less than one crater diameter to the south-southwest of Mutus crater.
The outer rim of Manzinus is worn, eroded, and somewhat irregular. The outer rim to the north-northeast is joined to the smaller 'Manzinus R' crater, and the crest along that side is lower and forms a saddle. There is a cluster of small craters along the southern side that partly overlap each other, consisting of the D, E, G, and N craters listed in the table below. The heavily eroded satellite crater 'Manzinus A' lies along the southeastern inner wall. Similarly the small crater 'Manzinus S' lies along the northern inner wall, and the cup-shaped 'Manzinus J' overlays the northwest rim.
The interior surface has been resurfaced in the past, and now forms a level, featureless plain that is marked only by a few tiny craterlets. The floor has the same albedo as the surrounding terrain.
Nearby Mutus is worn and eroded, with a pair of small but notable craters, 'Mutus A' and 'Mutus V', lying across the eastern rim. A number of other tiny craters lay along the rim and the interior wall. Another crater 'Mutus B' is located on the crater floor, just to the south of the mid-point. The remainder of the interior is relatively flat, and punctuated by several tiny craterlets to the north of 'Mutus B'. 2007/03/27. C14 @ F42. SKYnyx 2.0M.
Mare Humorum (the "sea of moisture".) The impact basin this mare it is located in is 825 kilometers across. It was not sampled by the Apollo program, so a precise age has not been determined. However, geologic mapping indicates that it is intermediate in age between the Imbrium and Nectaris Basins, suggesting an age of about 3.9 billion years. Humorum Basin is filled with a thick layer of mare basalt, believed to exceed 3 kilometers in thickness at the center of the basin. On the north edge of Mare Humorum is the large crater Gassendi, which was considered as a possible landing site for Apollo 17. 2006 January. C14 @ primefocus. LU075M.
Mare Orientale (the "eastern sea".) Like a target ring bull's-eye, the lunar mare Mare Orientale is one of the most striking large scale lunar features. Located on the extreme western edge of the lunar nearside, this impact basin is difficult to see from an Earthbound perspective.
Material from this basin was not sampled by the Apollo program so the basin's precise age is not known. However, it may be the freshest impact basin on the Moon and is believed to be slightly younger than the Imbrium Basin, which formed about 3.85 billion years ago. The surrounding basin material is of the Lower Imbrian epoch with the mare material being of the Upper Imbrian epoch.
The mare is about 900 kilometres (600 miles) across and was formed by the impact of an asteroid-sized object. Unlike most other basins on the Moon, Orientale is relatively unflooded by mare basalts, exposing much of the basin structure to view; the central portion of Mare Orientale is covered by a thin layer of mare basalt probably less than 1 kilometer deep, much less than in other nearside mare basins. The collision caused ripples in the lunar crust, resulting in the three concentric circular features. The innermost rings of this vast, multi-ringed crater are the inner and outer Montes Rook, and the outermost ring are the Montes Cordillera, 930 km in diameter. Basin ejecta begins just outside the Montes Cordillera and extends up to 500 kilometers beyond the base of the mountains. This ejecta has a rough, hummocky texture and contains linear patterns that point back at the center of Orientale.
This feature is believed to have first been given its modern name by the German astronomer Julius Franz in his 1906 book Der Mond. However, in his book On the Moon, Patrick Moore later claimed to have discovered and named this same feature in 1946. During the 1960s, rectified images of this area by Gerard Kuiper at the Lunar and Planetary Laboratory gave rise to the notion of this being an impact crater.
At the time this formation was named it was located on what by convention was considered the eastern side of the Moon, hence the latin name for "Eastern Sea". In 1961, however, the International Astronomical Union adopted the "astronautic convention" and this limb became the western edge. 2006/04/13. C14 @ primefocus. LU075M.
Mare Nectaris (Sea of Nectar) is a small lunar mare or sea (a volcanic lava plain noticeably darker than the rest of the moon's surface) located between the Sea of Tranquillity (Mare Tranquillatis) and the Sea of Fecundity (Mare Fecunditatis). The mare material is approximately 1km in depth, and mainly of the Nectarian and Lower Imbrian epochs, with the mare material of the Upper Imbrian epoch. The crater Theophilus on the northeastern side of the mare is of the Eratosthenian epoch. Thus, the crater is younger than the mare. The impact basin itself was formed around 3.8 to 3.9 billion years ago, when a large body impacted on the lunar surface. The the impact generated massive shock waves, which formed the prominent Rupes Altai escarpment marking the south-western rim of the impact basin (top right in the image.)
The Nectarian Period of the lunar geologic timescale runs from 3.9 billion years ago to 3.8 billion years ago. It is the period during which the Nectaris Basin and other major basins were formed by large impact events. Ejecta from Nectaris forms the upper part of the densely cratered terrain found in lunar highlands. 2006/12/09. C14 @ primefocus. SKYnyx 2.0M.
Mare Smythii (Latin for "Sea of William Henry Smyth") is a lunar mare located along the equator on the easternmost edge of the lunar near side. The Smythii basin where the mare is located is of the Pre-Nectarian epoch, the impact basin itself having formed some 4 billion years ago. While the surrounding features are of the Nectarian epoch. The mare material, which make up the floor of the mare, is a high aluminous basalt. The crater Neper is located to the north of the mare. This crater makes up part of the southern rim of Mare Marginis. Just off to the northwest of the mare are the craters Schubert and 'Schubert B'. The dark mare-filled crater at the southern edge of Smythii is the crater Kästner. 2006/11/05. C14 @ primfocus. SKYnyx 2.0M.
Marius is located on the Oceanus Procellarum. The surface to the west and north of this crater contains a large number of lunar domes (known as the Marius Hills) spread across an area over a hundred kilometers in diameter. It is the largest collection of such features in the same area on the lunar surface. Kepler is located to the east-southeast, and rays from it reach the rim of Maurius.
The floor of Marius has been flooded by basaltic lava, and the surface is relatively smooth and flat. There is no central rise, but a small craterlet 'Marius G' lies in the northeast part of the floor. The crater rim is low and generally circular in form.
The area of this crater was one of the locations proposed for an Apollo mission, but was subsequently cancelled. About 50 kilometers to the southeast was the landing site of the Luna 7 probe. 2006/11/04. C14 @ F41. LU075M.
Marius Rima is located close to the above Marius crater, and lies very close to the Marius C crater. It is a long meandering sinuous rille that winds it way across Oceanus Procellarum. It is about 250km long, and between around 2km to less than 1km wide at opposite ends. As with Rima Hadley, it is thought to be the remains of a collapsed lave tube. 2006/11/04. C14 @ F41. LU075M.
Maurolycus is one of the more prominent lunar craters in the southern highland region of the Moon that is covered in overlapping crater impacts. It is joined at the southeast rim by the smaller Barocius crater.
The outer wall of Maurolycus are tall, wide, and terraced; most notably in the eastern part. To the southeast the rim is lower and the crater is joined to what has the appearance of an overlain crater rim. The crater 'Maurolycius F' lies across the northwest rim, and that part of the crater floor is more rugged than the remainder. The other sections of the floor are relatively level, with a complex of central peaks and a pair of craterlets. The small crater 'Maurolycus A' is biting into the southern part of the rim. 2006/04/18. C14 @ F41. April 2005. C9.25 @ F42. LU075M.
Mercator & Campanus. Mercator is located on the southwest edge of Mare Nubium, in the southwest part of the Moon. It is located to the southeast of Campanus crater, and the two are separated by a narrow, winding valley. The Rupes Mercator fault is tangential with the northeastern outer rim of Mercator. The eastern edge of Palus Epidemiarum reaches the west rim of Mercator, and a rille from the Rimae Ramsden reaches the western rim at the site of the 'Mercator C' craterlet. The rim of Mercator is only somewhat eroded, and several tiny craterlets lie on the west and eastern rims. The interior floor has been flooded by lava in the past, leaving a relatively smooth and featureless surface.
Campanus is roughly circular, with an outward bulge along the western rim and an inward bulge to the north-northwest. The outer wall has not been significantly eroded, although it has a low saddle-point along the south. The interior floor has been resurfaced by basaltic-lava, leaving only a small central peak projecting above the surface. The floor has the same low albedo as the nearby mare, giving it a dark appearance. It is marked by a pair of tiny craterlets near the northeast and northwest interior walls. A slender rille crosses the crater floor from north to south, passing to the east of the central peak. 2006/04/10. C14 @ F41. LU075M.
Mercurius is an impact crater that is located in the northeastern part of the Moon. The rim of Mercurius is curcular, with a somewhat irregular edge. There are small outward bulges along several sections of the rim, with the most notable bulges being along the eastern and southern sides. The inner wall has slumped around much of the perimeter, producing a sharp edge. The sides are also somewhat worn, with some tiny craterlets overlaying the inner wall. Within the rim the interior floor has been resurfaced by lava and is nearly level, with a slight hint of a central mound. The remainder of the floor is marked only by a few tiny craterlets and some low ridges in the northeast corner. 2006/04/14. C14 @ F41. LU075M.
Mersenius & Rima Mersenius. Mersenius is located to the west of the Mare Humorum, on the southwest part of the Moon. The rim of Mersenius is heavily worn, especially in the low northern section. The crater 'Mersenius N' lies across the southwest rim. The interior has been flooded by basaltic-lava, which bludges upward forming a convex domed shape with an estimated height of 450 metres relative to the floor edges. This was most likely formed by lava upwelling beneath the surface. There are several tiny craterlets across the floor surface, but little in the way of a central peak. At least two faint rilles lie along the surface of the floor.
To the east of the crater on the surface and edges of the Mare Humorum is a rille system designated Rimae Mersenius. These rilles are generally parallel and run to the north-northeast for a length of about 230 kilometers. 2006/11/04. C14 @ f41. April 2005. C9.25 @ F42. LU075M.
Messala is a lunar crater of sufficient dimension to belong to the category of impact features known as walled plains. It is located in the northeastern part of the Moon, close enough to the rim to appear significantly foreshortened. The outer rim of this formation has received a significant amount of erosion due to minor impacts, but much of the outer wall retains its original shape and a certain degree of terracing. The rim is broken by smaller craters along the south, north, and northwest sides, designated 'Messala B', 'J', and 'K', respectively. 'Messala J' has a narrow gouge in its eastern rim leading a crater diameter to the east. It is attached to a slightly larger crater which lies across the southern rim of Schumacher.
The interior floor is relatively level but contains irregularities in the surface at some locations. There are several small craters across the floor, which are now little more than low rims and depressions in the surface. The most notable of these is a ghost-crater along the western inner wall. 2006/04/15. C14 @ F41. LU075M.
Messier is a relatively young impact crater located on the Mare Fecunditatis. The crater has a discernable oblong shape that is not caused by foreshortening. The longer dimension is oriented in an east-west direction. Just to the west lies 'Messier A', a similar-sized crater with an oblong, doublet form. The longer dimension of this crater is oriented north-south, at right angles to Messier crater. This crater also has a curved bulge extending to the west.
The interior of craters Messier and Messier A have a higher albedo than the surrounding maria. There is also a dark streak in the center of each crater. Two prominent, nearly linear rays extend westward from the rim of 'Messier A', continuing over 100 kilometers toward the east edge of Mare Fecunditatis. The maria about the craters is also lightly marked by rays from other craters.
It is theorized that Messier crater was formed by an impact at a very low angle, and that 'Messier A' could have formed following a rebound by the impacting body. The low angle of impact may also explain the asymmetrical ray system. 2006/04/16. C14 @ F41. LU075M.
Miller, Huggins & Nasireddin. Miller is an impact crater that lies amidst the rugged terrain in the southern part of the Moon. It is attached to the northern rim of the smaller Nasireddin crater, and the outer rampart of the later reaches almost to the central peak formation at the mid-point of the interior floor. Together with Huggins crater to the southwest this trio forms a chain of craters forming an arc that curves toward the north. The northwest rim of Miller in turn is attached to the satellite crater 'Miller C', forming the end of the arc.
The rim of Miller crater is nearly circular with a system of terraces along the inner wall. The interior floor is nearly level with the aforementioned central peak formation located at the mid-point. The crater 'Stöfler H' is attached to the exterior southeast rim and intrudes slightly into the interior. There are a few tiny craterlets lying within the crater, including one along the rampart of Nasiredden.
Huggins has been somewhat eroded, but the surviving rim remains relatively well-defined and is only overlaid by a few tiny craterlets. The western half of the interior floor is relatively level, although a small craterlet 'Huggins A' is attached to the inner wall of the northwest rim. There is a central peak formation next to the outer rampart of the intruding Nasireddin crater.
Nasireddin is a younger formation than the two craters it overlays, particularly the worn Huggins crater to the west. This crater retains much detail, including a terraced inner wall and a sharp rim to the south and east where the inner wall has slumped. The interior floor is relatively level, but rough-surfaced. There are a few low central peaks near the mid-point of the interior, and a few tiny craterlets to mark the surface. 2006/04/19. C14@ F41. LU075M.
Mons Gruithuisen Gamma & Delta. Mons Gruithuisen Gamma is a lunar dome that lies to the north of the Gruithuisen crater at the western edge of the Mare Imbrium. This massif is shaped as a rounded dome in the surface, occupying a diameter of 20 km and climbing gently to a height of 900 meters. At the crest is a small craterlet. This formation appears foreshortened when viewed from the Earth, and it has been described as resembling an "upturned bathtub". Next to it, lies the darker and more irregular dome of Mons Gruithuisen Delta. 2006/04/11 & 2006/11/04. C14 @ F41. LU075M.
Mons Rümker is an isolated volcanic formation that is located in the northwest part of the Moon's near side. The feature forms a large, elevated mound in the northern part of the Oceanus Procellarum. The mound has a diameter of 70 km, and climbs to a maximum elevation of about 500m.
The Mons Rümker has a concentration of lunar domes—rounded bulges across the top, some of which contain a small craterlet at the peak. These are wide, circular features with a gentle slope rising in elevation a few hundred meters to the mid-point. Lunar domes are the result of lava erupting from localized vents followed by relatively slow cooling. 2006/11/04. C14 @ F41. SKYnyx 2.0M.
Montes Recti is a mountain range on the northern part of the Moon's near side. It was given the Latin name for "Straight Range".
This is a small range of irregular ridges that is located in the northern part of the Mare Imbrium. Montes Recti is an unusually linear formation that forms a line from east to west. It is about 90 km in length, and only 20 km wide. The peaks rise to heights of up to 1.8 km. 2007/03/27. C14 @ F42. SKYnyx 2.0M.
Montes Spitzbergen (latin for "Spitzbergen Mountains") is a solitary mountain chain in the eastern Mare Imbrium. They are located about a crater diameter to the north of the prominent, flooded Archimedes crater. They lie within a diameter of 60 km. The range trends from south to north, and they have a maximum width of about 25 km. This range consists of a number of peaks separated by lava-flooded valleys. This range is most likely the surviving rim or inner ring of an impact crater that has been buried under magma flows. This range was so named by Mary Blagg for their resemblance to the jagged terrestrial mountains of Spitzbergen island of the Svalbard archipelago. 2006/04/20. C14 @ F41. LU075M.
Montes Teneriffe is a range on the northern part of the Moon's near side. It was named after Tenerife, one of the Canary Islands. This range is located in the northern part of the Mare Imbrium, to the southwest of Plato crater. The Montes Teneriffe lie within a diameter of about 110 kilometers, although the peaks only occupy a small part of that region. The formation consists of a few scattered ridges surrounded by the lunar mare. Individual peaks rise to heights of up to 2.4 km. 2006/04/20. C14 @ F41. LU075M.
Moretus is a prominent impact crater located in the heavily-cratered highland region near the south pole. South of Moretus is Short crater, while to the north is Cysatus. Due to the location near the lunar limb, the crater appears oblong because of foreshortening. The rim of the crater has a wide, terraced inner wall, and a complex outer rampart. The floor has been partly resurfaced and is relatively flat. In the middle is a central mountain formation that rises about 2.1 kilometers above the surrounding floor. 2006/04/10 & 2005/11/20. C14 @ F41. LU075M.
Neper is an old impact crater located near the eastern limb of the Moon. Due to its location the crater must be viewed during a suitable libration, and is very foreshortened. Neper lies on the south edge of Mare Marginis. The crater inner walls have worn terraces, with low rim edges at the northern and southern extremes. The crater floor is dark and flat, with a central peak and several crater impacts near the west rim. The most notable of these is a small crater near the north-northwestern edge. 2006/11/05. C14 @ F25. SKYnyx 2.0M.
Newton is located near the south limb of the Moon. It is south-southwest of Moretus crater. Because of its location, the crater appears highly oblong due to foreshortening. It is considered the deepest crater on the near side of the Moon.
The interior of the Newton is a picture in contrasts. The southern end has been covered, possibly by lava flows or ejecta, leaving a relatively flat surface that is marked only by tiny craters and a slight wrinkle-ridge down the middle. The northern half is rugged and irregular, with the satellite crater 'Newton D' overlaying the north-northeastern rim and extending across nearly half the crater diameter.
The rim in the south is relatively low and narrow, with the smaller crater 'Newton G' partly overlaid and flooded by lava. This adjacent crater forms a step up from the interior of Newton crater, and there is a tiny rille in the south floor of Newton where it appears as if a channel flowed down the side from 'Newton G'. The other parts of the outer crater wall are much wider than in the south end, particularly in the areas adjacent to 'Newton D'. 2006/04/10 & 11. C14 @ F41. LU075M.
O' Neils Bridge. One of the most controversial features of recent times in lunar observation. It is located near Promontorium Olivium on the western edge of Mare Crisium. A American amateur astronomer, O' Neil claimed there was a bridge over the western edge of the Mare Crisium back in the 1950s. The BAA lunar section director H.P Wilkins then drew the feature and claimed it was real, and artificial - even going so far as to suggest it was a UFO lodged in the surface!. Needless to say these claims created rifts in the observing community at the time, and ended with Wilkins losing his directorship. The bridge is actually an optical illusion created by light and shadow cast over the terrain. See the Jan 1998 S&T for further information about this feature. 2006/04/16. C14 @ F41. LU075M.
Orontius is an impact crater that lies in the heavily-cratered southern highlands of the Moon's near side. The eastern part of the crater is overlaid by the smaller Huggins crater, which is overlain in turn on its eastern rim by the still smaller Nasireddin crater, the trio forming a crater chain of diminishing dimensions. The rim of Orontius is battered, worn, and overlain by a number of different craters. A pair of craters to the west have intruded into the crater wall, forming inward bulges. Little of the original wall remains nearly intact, with the south and southwestern rim having survived the erosion process better than the other wall sections.
The southwest half of the crater floor is still fairly flat and marred only by a few small craterlets. In the north of the crater, the distorted feature 'Orontius F' forms a distorted, crater-like oval. 2006/04/20. C14 @ F41. LU075M.
Pascal lies near the northern limb of the Moon, on the western side of the pole. Pascal can be located by finding the Carpenter crater and then following the surface to the northwest toward the limb. However the visibility of this formation can be affected by libration. Carpenter can be seen in the foreground of the above image. Within the wide inner walls is a nearly level interior floor that has been resurfaced by lava. At the mid-point is a low ridge, forming a minor central peak. There are tiny craters at the north end of the floor, and at the northeast end of the central ridge. There is also a small chain of craterlets lying across the northeast inner wall.
Just to the north of Pascal is 'Poncelet C', a satellite crater of the lava-flooded Poncelet to the east. The rim of this crater is bisected by several grooves in the surface, one of which crosses the southeast rim and cuts across tangentially to the northeast rim of Pascal. 2006/04/13. C14 @ F41. LU075M.
Petavius is a large impact crater located to the southeast of the Mare Fecunditatis, near the southeastern lunar limb. Attached to the northwest rim is the smaller Wrottesley crater. The outer wall of Petavius is unusually wide in proportion to the diameter, and displays a double-rim along the south and west sides. The height of the rim varies by as much as 50% from the lowest point, and a number of ridges radiate outward from the rim. The convex crater floor has been resurfaced by lava flow, and displays a rille system named the Rimae Petavius. The large central mountains are a prominent formation with multiple peaks, climbing 1.7 kilometers above the floor. A deep fracture runs from the peaks toward the southwest rim of the crater.
70cm radar images of this crater and its surroundings show that the region of the surface beyond the wide outer rampart of Petavius has a dark halo, characteristic of a smooth surface free of boulders. It is thought that this may have been created by radial outbursts during the original impact that swept the area "clean". 2006/11/06. C14 @ F41. SKYnyx 2.0M.
Petermann & Cusanus. Petermann is located near the northern limb of the Moon, on the eastern hemisphere. It is located just to the north of the Cusanus crater, and the two are separated by a distance of about 10 kilometers. Due to its location, this crater appears significantly foreshortened when viewed from the Earth, and its visibility can be affected by libration.
Attached to the western rim of this crater is the large, heavily eroded crater 'Petermann R', which is much larger than Petermann although less prominent in appearance. The outer rim of Petermann crater is eroded, but retains some structure including traces of terraces. The inner wall varies in width around the perimeter, being wider to the south and southeast near Cusanus. The interior floor has been resurfaced, leaving a level plain that is marked only by a number of tiny craterlets and only a few low ridges near the sides.
The rim of Cusanus has been eroded and rounded due to a history of minor impacts. The terraces are still visible along the inner walls, although they are less sharply-defined compared to younger crater formations. A pair of tiny craters form a notch along the eastern rim, and there is a slight inward bulge along the western inner wall. The interior has been resurfaced with lava, leaving a flat and relatively featureless floor. But the lava was not of sufficient depth to significantly reduce the width of the inner walls. 2006/04/14. C14 @ F41. LU075M.
Pitiscus is a lunar impact crater that lies in the southern part of the Moon's near side, just to the northwest of the larger Hommel crater. The crater is worn, but still forms a prominent feature upon the surface. The rim is roughly circular, but appears oval from the Earth due to foreshortening. There is an outward bulge to the south-southeast where the interior has slumped. The remainder of the inner wall still displays terraces, although they are worn and rounded due to erosion.
The interior floor is level and appears to have been resurfaced by lava. There is a low central peak formation at the mid-point of the interior, and the northern end of this ridge is overlaid by the circular craterlet 'Pitiscus A'. A slumped and somewhat irregular crater 'Pitiscus E' lies along the inner wall to the west-southwest. The interior floor is also marked by several other tiny craterlets alongside the eastern interior wall. 2007/03/27. C14 @ F42. SKYnyx 2.0M.
Philolaus is an impact crater that is located in the northern part of the Moon's near side. It overlays the older and heavily worn 'Philolaus C' to the south. This crater retains a well-defined form that has not changed significantly since it was originally created. The outer rim edge is roughly circular, but with a somewhat irregular edge that displays signs of slumping. The most notable slum is a triangular area along the eastern rim. The inner wall of the crater has a complex system of terraces with a sharp-edged rim in locations where slumping has occurred. On the exterior of the rim is an outer rampart that extends outward nearly half a crater diameter in all directions.
The interior floor is irregular with rough areas about the center and to the northeast. There is no single central peak, but rather a pair of peaks offset to the south and the east of the middle. There is also a smaller ridge pair offset to the northwest. The flattest part of the interior floor is in the northeast of the crater interior. The floor is not significantly marked by impacts. 2006/04/19 & 21. C14 @ F41. LU075M.
Phocylides, Nasymyth & Wargentin. Phocylides is located near the southwest rim of the Moon. It overlays the south rim of Nasmyth crater to the north. To the northwest is the unusual plateau formation of Wargentin crater. The outer wall of Phocylides is worn and eroded, especially along the western edge. The northern edge of the rim is notched and irregular, with a rise of ground joining the south rim of Wargentin. The crater Phocylides F lies across the southern rim. The floor of Phocylides is flooded and relatively smooth, with a few small craterlets and no central peak. The most notable impact on the floor is a crater near the northeast rim.
Nasmyth is worn and impacted in several locations by craterlets, most notably 'Nasmyth D' which lies across the north rim. The floor has been flooded by lava flows in the past, making the surface relatively flat and the rim low. There is no central peak within the crater, but the floor is impacted by some small craterlets.
Wargentin is an unusual form of lunar impact crater. The interior has been completely filled up to the edge of its raised rim by a basaltic lava flow, so that it forms a raised plateau above the surroundings. When the lava flow occurred, it erupted from within the crater walls and proceeded to accumulate until overrunning the lowest portion of the rim. Some blockage then prevented the lava flow from returning to equilibrium. Since this occurred, some ejecta has been deposited across the top, giving the surface a higher albedo than is typical for deposits of basalt.
The rim of Wargentin is somewhat worn and is overlain by a few small craters. The outer wall climbs to a height of 0.3 km above the surrounding terrain. A spoked pattern of wrinkle ridges can be discerned on the surface, radiating from the center of the crater. 2006/04/12 & 11. C14 @ F41. LU075M.
Piccolomini is a prominent impact crater located in the southeastern sector of the Moon. The crater rim has not been severely worn by crater impacts, and the inner wall possesses wide terraces. These structures have been somewhat smoothed by landslips and erosion, most likely induced by seismic activity. An influx of material has entered across the northern rim, flowing down toward the base. Piccolomini's floor is relatively smooth, with only minor hills and impact craters. In the middle is a complex central peak surrounded by lesser mounts. The main peak rises to a height of 2.0 kilometers above the surrounding floor. 2005/09/22. C14 @ F41. LU075M.
Pitatus & Hesiodus. Pitatus is an ancient impact crater located at the southern edge of Mare Nubium. Joined to the northwest rim is Hesiodus crater, and the two are joined by a narrow cleft. The complex wall of Pitatus is heavily worn, and has been encroached by lava flows. The rim is lowest to the north, where the lava almost joins the Mare Imbrium. Near the middle is a low central peak that is offset to the northwest of center. This peak only rises to a height of 0.5 km.
Pitatus is a floor-fractured crater, meaning it was flooded from the interior by magma intrusion through cracks and openings. (See also the Gassendi and Posidonius craters for similar features.) The flooded crater floor contains low hills in the east and a system of slender clefts named the Rimae Pitatus. The larger and more spectacular of these rilles follow the edges of the inner walls, especially in the northern and eastern halves. The floor also contains the faint traces of deposited ray markings.
Just to the north of Pitatus in the neighboring maria is the half-buried rim of a lesser crater, covered in the past when Mare Nubium was formed. 2006/04/08. C14 @ F41. LU075M.
Plato is the maria-surfaced remains of an impact crater. It is located on the northeastern shore of the Mare Imbrium, at the western extremity of the Montes Alpes mountainous range. The age of the Plato walled-plain is about 3 billion years; younger than the Mare Imbrium to the south. The rim is irregular with 2-km-tall jagged peaks that project prominent shadows across the crater floor when the sun is at a low angle. Sections of the inner wall display signs of past slumping, most notably a large triangular slide along the western side. The rim of Plato is circular, but from the Earth it appears oblong due to foreshortening.
The flat floor of Plato has a relatively low albedo, making it appear dark in comparison to the surrounding rugged terrain. The floor is free of significant impact craters and lacks a central peak. However there are a few small craterlets scattered across the floor. Plato has developed a reputation for various transient lunar phenomenon, including flashes of light, unusual color patterns, and areas of hazy visibility. These anomalies are likely a result of seeing conditions, combined with the effects of different illumination angles of the Sun. The astronomer Johannes Hevelius originally called this feature the 'Greater Black Lake'. 2006/04/20. C14 @ F41. LU075M.
Pontécoulant is a prominent impact crater that is located in the southeastern part of the Moon. Due to its position, the crater appears foreshortened from the Earth and it is difficult to observe much detail. This crater has terraced inner wall that is nearly circular, but with an outward extension to the southeast. The rim is somewhat worn but retains much detail. The crater partly overlays the older and smaller 'Pontécoulant E' along the south rim, and has several tiny craterlets on the eastern inner wall and one to the southwest.
The inner floor is nearly flat, with some rough ground near the southern rim and some low central peaks located southwest of the mid-point. There is a small but prominent crater located at the center of the floor, and several other tiny craterlets scattered across the inner surface. 2006/11/05. C14 @ F25. SKYnyx 2.0M.
Posidonius is an impact crater that is located on the western edge of Mare Serenitatis, to the south of Lacus Somniorum. The Chacornac crater is attached to the southeast rim. The rim of Posidonius is shallow and obscured, especially on the western edge, and the interior has been overlaid by a lava flow in the past. The crater ramparts can still be observed to the south and east of the crater rim, and to a lesser degree to the north.
There is a smaller, semi-circular rim of a concentric, flooded crater within the main rim, offset toward the eastern edge. There is no central peak, but the floor is hilly and laced with a rille system named the Rimae Posidonius. The floor is also slightly bulged due to the past lava uplift, which also likely produced the complex of rilles. The northeast rim is interrupted by the smaller crater 'Posidonius B'. Within the crater rim, offset just to the west of center is another smaller crater 'Posidonius A'.
On the Mare Serenitatis surface near Posidonius crater is a notable system of wrinkle-ridges that parallel the nearby shore. These are designated the Dorsa Smirnov. At the peak of these ridges is a small craterlet with a diameter of 2 km. This craterlet is surrounded by a patch of high-albedo material, and is an example of a lunar bright spot. This peak was formerly designated Posidonius Gamma. The Posidonius Gamma feature was first observed by the lunar cartographer Julius Schmidt in 1857. He noted the similarity to the bright patch surrounding Linné crater. 2005/09/22 & 2005/11/20. C14 @ F41. LU075M.
Prinz is the lava-flooded remains of a lunar crater on the Oceanus Procellarum lunar mare. The formation lies to the northeast of the prominent Aristarchus crater.
The rim of Prinz is the most intact in the northeast half, while a large gap exists in the southern end of the crater wall. The rim climbs to a maximum height of 1.0 km above the base. It is attached along the eastern rim by a low ridge that is part of the foothills of the small Montes Harbinger mountains to the northeast. The region of the maria about Prinz is marked by rays from the Aristarchus crater
Just to the north of Prinz crater is a system of rilles designated the Rimae Prinz. These are sinuous in nature and extend for up to 80 kilometers. The tiny crater Vera is only a couple of kilometers to the north of Prinz crater rim, and serves as the origin of one of these rilles. Within the same rille complex is the tiny crater Ivan. The crater Vera was previously identified as 'Prinz A', and Ivan as 'Prinz B', before they were assigned names by the IAU. 2006/04/11. C14 @ F41. LU075M.
Ptolemaeus is well-known and ancient impact crater close to the centre of Moon. The features of Ptolemaeus are highlighted when the sun is at low angles during the first and last quarter. The crater has a low, irregular outer rim that is heavily worn and impacted with multiple smaller craters. The rim has a discernable polygonal shape, although overall it remains circular. The largest of the peaks along the rim, designated Ptolemaeus Gamma (γ), has an altitude of 2.9km and is located along the northwest rim. The crater has no central peak, a lava-flooded floor, and lacks a ray system. Impact sites of this form are often classified as a "walled-plain", due to their resemblance to the maria.
The somewhat dark-hued floor of Ptolemaeus is notable for several "ghost" craters, formed when lava flow covers a pre-existing crater. These leave only a slight rise where the rim existed, and are difficult to detect except at low angles of sunlight. There are also multiple smaller craters across the floor surface, most notably Ammonius crater in the north-eastern quadrant.
On either of this crater are a linear, irregular gashes in the lunar surface, forming valley-like features. These features are approximately parallel to each other and radiate from the direction of Mare Imbrium to the north-northwest. 2006/04/20. C14 @ F41. LU075M.
Purbach & Regiomontanus. Purbach is a large crater located in the rugged southern highlands of the Moon. The distorted crater Regiomontanus is attached to the southern rim. The outer wall of Purbach is heavily worn, with the most intact section being along the east and northeast sides. The shared rim between Purbach and Regiomontanus is incised and rugged.
The wall is distorted along the western edge, giving the appearance of a double-rim, with the second rim distended toward the west. The northern wall is almost completely destroyed, and somewhat irregular 'Purbach G' lies across the northwest rim. The crater floor is relatively smooth in the eastern half, with a low series of ridges and a partial "ghost-crater" outline just to the west of the crater mid-point. If the crater possessed a central peak, it has either been removed or forms part of the ridges to the west.
Regiomontanus is heavily worn from impact erosion, and the rim is irregular, mountainous and distinctly oval in outline. The walls on the south and west edges have been almost completely degraded. A prominent ridge lies off center to the northwest, with the small crater 'Regiomontanus A' at its summit. The crater floor is lava-flooded, and has a number of small crater impacts. The summit crater 'Regiomontanus A' was once considered proof of volcanic activity on the Moon. However this feature is actually an impact crater, and is offset slightly from the summit of the central peak. 2006/04/20. C14 @ F41. LU075M.
Pythagoras is a prominent lunar impact crater located near the northwestern lunar limb. The crater has an oval appearance due to the oblique viewing angle. The well-preserved rim of Pythagoras crater has a wide terrace system, and a slight rampart around the exterior. Although generally circular, observers note that the crater outline has a hexagonal form. The floor is flattened, but with an irregular, hilly surface. There is evidence of landslips around the periphery. In the center is a sharp, moutainous rise with a double-peak that ascends 1.5 kilometers above the crater floor. 2006/04/21. C14 @ F41. LU075M.
Pytheas is a small impact crater located on the southern part of the Mare Imbrium, to the south of Lambert crater. It has a sharply-defined rim, a hummocky outer rampart, and an irregular interior due to slumping or fall-back. There is a small crater along the northern outer rampart, and a similar crater about 20 km to the west. Pytheas possesses a small ray system that extends for a radius of about 50 kilometers. It is surrounded by lunar mare that is dusted with ray material from Copernicus crater to the south. 2006/04/09. C14 @ F41. LU075M.
Reiner Gamma is an albedo feature that is located on the Oceanus Procellarum, to the west of the Reiner crater. It has an overall dimension of about 70 kilometers. The feature has a higher albedo than the relatively dark mare surface, with a diffuse appearance and a distinctive swirling, concentric oval shape. Related albedo features continue across the surface to the east and southwest, forming loop-like patterns over the maria.
The Reiner Gamma feature is not associated with any particular irregularities in the surface, and so the cause was a mystery until similar features were discovered in Mare Ingenii and Mare Marginis on photographs taken by orbiting spacecraft. The feature on Mare Ingenii is located at the lunar opposite point from the center of Mare Imbrium. Likewise the feature on Mare Marginis is opposite the mid-point of Mare Orientale. Thus it is believed that the feature resulted from seismic energies generated by the impacts that created these maria. Unfortunately there is no such lunar mare formation located precisely on the opposite surface of the Moon, although the large Tsiolkovskiy crater lies within one crater diameter.
The central feature of the Reiner Gamma does bear a resemblance to the dipolar formation created by iron filings on a surface with a bar magnet on the underside. Low-orbiting spacecraft have observed a relatively strong magnetic field associated with each of these albedo markings. Some have speculated that this magnetic field and the patterns were created by cometary impacts. However the true cause remains uncertain.
The magnitude of the Reiner Gamma feature has a field strength of approximately 15 nT, measured from an altitude of 28 km. This is one of the strongest localized magnetic anomalies on the Moon. The surface field strength of this feature may be sufficient to form a mini-magnetosphere, which could deflect the solar wind. As the particles in the solar wind are known to darken the lunar surface, the magnetic field at this site may account for the survival of this albedo feature. 2006/04/12. 2006/11/04. C14 @ F41. LU075M.
Reinhold is a prominent impact crater that lies to the south-southwest of Copernicus crater, on the Mare Insularum. The interior walls are terraced and the irregular outer ramparts are visible against the flat surface of the mare. The interior floor of Reinhold is relatively featureless, with only a few low rises. Just to the northeast is a low, flooded crater designated 'Reinhold B'. 2006/04/21. C14 @ F41. LU075M.
Rheita & Rheita E. Rheita is an impact crater located in the southwestern sector of the moon. The southwestern rim overlays the edge of Vallis Rheita, a long lunar valley strentching for over 200 kilometers. The rim of Rheita crater remains well-defined with a sharp lip and a terraced inner wall. The rim overlaps a slightly smaller crater to the east, and has a pair of small impact craters in the northern wall. The crater floor is flat and it has a central peak. Rheita E is an interesting satellite crater that appears very similar to the larger and more famous Schiller crater. It spans 66 x 32km in size, and is possibly the result of overlaying multiple impacts. 2006/11/06. C14 @ F41. SKYnyx 2.0M.
Ritter & Sabine. Ritter is a lunar crater located near the southwest edge of Mare Tranquillitatis. It is the northwest member of a crater pair with Sabine crater to the southeast. The two rims are separated by a narrow valley only a couple of kilometers wide. This crater is roughly circular but with an irregular outer rim. The inner walls have slumped down toward the floor. The interior is irregular with several low ridges. To the northwest of Ritter crater is a system of parallel rilles designated Rimae Ritter. These follow a course to the northwest.
Sabine's outer rim is roughly circular and relatively featureless. The interior floor has a pair of small craterlets and a central rise. There is a ridge at the western edge of the floor that is concentric with the inner wall. About 85 km to the east-southeast is Statio Tranquillitatis, the landing site of the Apollo 11 mission and the first human beings to step on the Moon. 2006/11/20. C14 @ F41. LU075M.
Rosenberger & Vlacq. Rosenberger is an old impact crater in the southeastern part of the Moon. Due to foreshortening, this crater appears oval when viewed from the Earth. From orbit, however the crater rim is nearly circular. This crater is located in a region rich with prominent craters. The slightly smaller Vlacq crater is nearly attached to the northwestern outer rim of Rosenberger.
This crater has been heavily eroded by a history of impacts, so that the outer rim has become rounded and somewhat indistinct. As a result the crater possesses only a shallow rise along the rim edge, and it nearly forms a circular depression in the surface. The satellite crater 'Rosenberg D', which is about 50 kilometers in diameter, is intruding into the southern rim of Rosenberger. A number of smaller, worn impact craters lie along the remainder of the rim and inner wall. The interior floor of this crater forms a relatively level surface that is marked by several small craterlets. To the south-southeast of the mid-point is the worn remains of a small crater. At the mid-point there is a low central peak joined to a small craterlet to the north.
For information regarding the Vlacq crater, see further down the page. 2006/04/15. C14 @ F41. LU075M.
Rost is an impact crater that is located in the southwest part of the Moon, to the southeast of the elongated Schiller crater. This crater is a circular formation with a low rim and a relatively featureless inner wall and interior floor. There are some tiny craterlets around the rim, including one across the northwest wall and another on the inner wall to the south. The interior has no significant features. The similar sized crater attached to Rost is Rost A. 2006/04/10. C14 @ F41. LU075M.
Rupes Recta (latin for "Straight Fault") is a linear fault on the Moon, in the southeastern part of the Mare Nubium. It is more commonly known as "the straight wall". When the sun illuminates the feature at an oblique angle at about day 8 of the lunar orbit, the Rupes Recta casts a wide shadow that gives it the appearance of a steep cliff. The fault has a length of 110 km, a typical width of 2-3 km, and a height of 240-300 m. Thus although it appears to be a vertical cliff in the lunar surface, the grade of the slope is actually relatively shallow at somewhere between 10-20degrees.
To the west of this escarpment is the Birt crater, which is about 10.5 miles in diameter. Also to the west is the Rima Birt rille. At the southern end is a group of hills often called the "Stag's-Horn Mountains", although this name is not officially recognized by the IAU. 2006/04/20 & 2006/10/14. C14 @ F41. LU075M.
Rutherfurd is an impact crater located entirely within the southern rim of the much larger Clavius crater. Rutherfurd forms the larger member in an arcing chain of craters of decreasing size that curve across the floor of Clavius crater. The craters in this chain do not appear to be the same age, so this formation is most likely random in nature.
Rutherfurd is somewhat oval in shape, with the long axis oriented approximately in a north-south direction. The northern outer ramparts have a series of radiating ridges on the floor of Clavius crater. The rim is overlaying the inner wall of Clavius, and thus the rim of Rutherfurd is higher above the surface along the north and west sides. The floor is irregular in shape, and there is a central peak somewhat offset to the northeast. The ejecta pattern; oblong shape, and location of the central peak indicate the original impact may have been at a low angle from the southeast. 2005/11/20. C14 @ F41. LU075M.
Santbech is an impact crater that is located to the southeast of Mare Nectaris. The terrain about the crater, although rugged in places, has been flooded by lava and so has a low albedo and a relatively flat surface. The outer rim of Santbech stands above the surrounding terrain, with an irregular outer rampart. The rim perimeter is somewhat irregular, and has been disturbed in several locations by subsequent impacts. There are small craters along the eastern and northwestern rim, and an asymmetrical formation along the southern inner wall. The northern rim is uneven, with a diagonal gouge running to the southeast. Much of the interior floor is level and nearly featureless, with a small central peak offset to the north-northeast of the mid-point. 2006/04/16. C14 @ F41. LU075M.
Schickard is a large impact crater of the form called a walled-plain. It lies in the southwest sector of the moon, near the lunar limb. As a result the crater appears oblong due to foreshortening. Attached to the northern rim is the lesser Lehmann crater, and to the northeast is the even smaller Drebbel crater. Southeast of Schickard is the Wargentin lava-flooded plateau.
Schickard has a worn rim that is overlaid in several locations by smaller impact craters. The most prominent of these is irregular Schickard E crater across the southeast rim. Schickard's floor has been partially flooded by lava, leaving only the southwest portion uncovered and rough-textured. The floor is marked with a triangular band of lighter-albedo material, leaving relatively darker patches in the north and southeast. This feature is more prominent when the sun is at a relatively high angle. There are also multiple small crater impacts on the floor, most notably in the southeast. 2006/11/04. C14 @ F41. LU075M.
Scheiner is an impact crater that lies to the west of the enormous Clavius walled-plain. The rim of Scheiner is worn, eroded, and marked with multiple impacts. It is the most heavily worn in the northern part, where a cluster of craterlets covers the entrance to a low valley leading to the north. The floor of the crater has several craterlets, including 'Scheiner A' that lies near the mid-point. 2006/04/10. C14 @ F41. LU075M.
Schiller is an oddly-shaped impact crater located in the southwest sector of the moon. To the east is the Bayer crater. The rim of Schiller has an elongated shape that is amplified by its proximity to the lunar limb. The long axis lies along a line running northwest-southeast, with the wider girth located in the southeastern half. There is a slight bend in the elongation, with the concave side facing to the northeast. Observers have noted that Schiller appears to be a fusion of two or more craters. It bears a superficial resemblance to the footprint left by a shoe.
The crater rim is well-defined, with a terraced inner wall and a slight outer rampart. At the southeast end, a smaller crater is connected to Schiller by a wide valley. Most of the Schiller crater floor is flat, most likely due to lava flooding. There are some bright patches that are most clearly visible under a high sun angle. A double-ridge lies along the center of the northwest crater floor, forming a nearly linear formation that divides the floor in half. 2006/11/04, 2006/04/21 & 2005/08/29. C14 @ F41. LU075M.
Schlüter is an impact crater that is located near the western limb of the Moon's near side. It lies along the northwestern face of the Montes Cordillera mountain range that encircles the Mare Orientale. This crater has an irregular outer rim that is roughly circular, with small outward bulges to the north and southeast. The former section displays a slumped appearance along the inner wall. The southern rim contains a small double-crater that lies long the inner wall. The rim is otherwise not significantly eroded, and contains a system of terraces along the inner sides.
The interior floor of Schluter has a curved patch of low albedo material along the northern inner wall, nearly matching the dark shade of the Lacus Autumni to the south of the Montes Cordillera range. The remainder of the floor has the same albedo as the surrounding terrain. In the mid-point of the floor is a central peak, consisting of an elongated ridge with the long dimension aligned in a northerly direction. There is a slender rille near the northwestern inner wall. 2006/04/13. C14 @ F41. LU075M. 2005 April. C9.25 @ F42. LU075M.
Schomberger is a prominent impact crater that lies in the southern part of the Moon, in the area near the limb. The relatively young satellite crater 'Schomberger A' is nearly attached to the southern rim, and the much-aged 'Schomberger C' lies just off the western rim. This is a relatively well-defined crater with sharp features that have not been significantly worn down by minor impacts. The rim is roughly circular and sharp-edged, with a complex inner wall marked by slumping and many ridges and terraces. The inner floor is relatively flat and level, although somewhat rougher in the western half. At the mid-point of the interior is a central peak complex formed by several ridges. 2006/04/10. C14 @ F41. LU075M.
Sharp is an impact crater located to the west of the Sinus Iridum bay, beyond the Montes Jura range. Due to its location, the Sharp crater appears oblong because of foreshortening. The crater rim is actually circular. Sharp is surrounded by a rugged region of mounts and rises. Ridges are joined to the north and south ends of the rim. The crater has a low central peak at the mid-point of the floor. Between Sharp and 'Sharp A' is an unnamed sinuous rille. The more distant Rima Sharp is located on the Mare Frigoris to the northwest. 2006/11/04. C14 @ F41. SKYnyx 2.0M.
Sheepshanks Rima. This extremely narrow sinuous rille runs for 200km across the Mare Frigoris and is a very challenging feature to observe. It is pitted my numerous tiny craterlets along its length. 2005/11/20. C14 @ F41. LU075M.
Sirsalis is a relatively young impact crater located near the western lunar limb, to the southwest of the Oceanus Procellarum. The crater lies across a ridge that runs in a north-south direction. It has a sharp edge and a low central peak. The crater overlaps a slightly larger and older crater 'Sirsalis A' to the west-southwest, and the two form a distinctive feature. To the east is a rille system named the Rimae Sirsalis. The longest of these rilles follows a line running approximately north-northeast to south-southwest, just clearing the southeastern rim of Sirsalis crater by about 10 kilometers. This long rille runs 330 kilometers from the shore of Oceanus Procellarum until it crosses the crater 'Darwin A' and intersects the Rimae Darwin to the east of Darwin crater. 2006/04/12. C14 @ F41. LU075M.
Southern Highlands. Perhaps one of the most dramatic and frequently photographed areas of the Moon. This area encompasses a wide array of dramatic terrain, and several prominent craters. At the bottom Tycho and Longomontanus dominate, while at centre, the huge walled plain of Clavius is centre stage. To its south lies Blancanus, Schiener and Moretus. Further south toward the lunar south pole is the Klaproth & Casatus pair. Further south still is Newton, and near the very limb is the mountains marking the Amundsen/Scott craters. 2006/02/10. C14 @ primefocus. LU075M.
Snellius is located near the southeast limb of the Moon. Because of fore shortening the crater appears oval in shape, although it is actually nearly round. To the northeast is the large Petavius crater. South of Snellius is the Stevinus crater.
The rim of Snellius is heavily worn and eroded, with overlapping craterlets. The floor is somewhat irregular and uneven. The western rim marks the start of the Vallis Snellius, one of the longest valleys on the Moon. It continues nearly 500 kilometers to the northwest to near the edge of Mare Nectaris. Its origin is most likely associated with the formation of the lunar mare. Just to the northwest is 'Snellius A', a crater with a notable ray system that overlaps the southwest reaches of Mare Fecunditatis to the north. 2005/12/20. C14 @ F41. LU075M.
Stadius is a ghostly remnant of an ancient lunar crater that has been nearly obliterated by basaltic lava flow. It lies to the southwest of the much younger Eratosthenes crater, at the north edge of Mare Insularum where the mare joins Sinus Aestuum. To the west is the prominent Copernicus crater, and multiple secondary craters from the Copernican ejecta cover this area. To the northwest is a chain of craters that continue in a roughly linear formation until reaching Mare Imbrium. Only the northwestern rim of Stadius crater remains nearly intact, and it joins with a north-running ridge line that reaches the western rampart of Eratosthenes crater. The remainder of the formation forms a ghostly trace of the original rim, created from a few rises in the surface, and there is no indication of a central peak. The flat crater floor is pock-marked by craterlets. 2006/04/20. C14 @ F41. LU075M.
Stevinus is an impact crater located in the southeast part of the Moon. To the southeast is the large Furnerius crater. Stevinus has a high inner wall and a central peak at the mid-point of the interior floor. The inner walls are slumped, so that the side slopes down sharply, then more gradually. There are several small ridges on the floor, in addition to the peak. To the west-northwest of Stevenus is the tiny crater 'Stevenus A', a feature that possesses a small ray system and a displays a high albedo. 2006/04/15 & 2005/12/20. C14 @ F41. LU075M.
Steinheil & Watt. Steinheil is an impact crater that is located in the rugged highlands in the southeastern part of the Moon. It forms a prominent crater pair with the similar-sized Watt crater, which it partly overlays to the southeast. To the northwest is the large Janssen walled-plain. Due to the location of this crater, it appears foreshortened when viewed from the Earth. This is a relatively circular crater that has undergone some light erosion from subsequent impacts. The inner wall is wider along the southwestern rim than elsewhere, and there is a slight outward bulge in the western rim. There are a few tiny craterlets along the rim and inner wall, the most notable being a crater at the base of the inner noirtheast rim. The interior floor is level, with no central peak and only a few minor craterlets.
The northwestern third of Watt's rim has been completely overlaid by the same-sized Steinheil crater, leaving much of the interior floor covered with the outer rampart of ejecta from the later formation. The remainder of the rim of Watt crater is somewhat jagged in appearance, with an inward bulge along the southeast rim and a pair of small outward projections to the northeast. The rim is otherwise relatively sharply-defined, with only a minor amount of wear. 2006/11/06 & 2005/12/20. C14 @ F41. LU075M.
Stöfler is a large impact crater located in the crater-riddled southern highlands.The Faraday crater has overlain and damaged the western rim, and this crater in turn has been overlaid by several smaller craters. The rim of Stöfler is worn and eroded, but the outline remains relatively intact except where overlain by Faraday. The smaller 'Stöfler K' intrudes into the northwest rim, and 'Stöfler F' forms an indentation into the base of the southwest interior wall.
The crater floor has been filled in with deposits, either from lava flows or ejecta from basin impacts, and is relatively flat and featureless in the northwest half. If there was a central peak, it has now become buried. The floor has a low albedo, making the crater relatively easy to identify as it is one of the few craters in this region of the lunar surface that have a dark floor. Traces of bright ray material from Tycho crater, located to the west, can been seen across the floor. 2006/04/19. C14 @ F41. LU075M.
Taruntius is located on the northwest edge of Mare Fecunditatis. The surface about Taruntius has an unusual number of ghost-craters and lava-flooded features, especially to the southwest in the Mare Fecunditatis. The outer rim of Taruntius is shallow, but forms a veined, complex rampart in the nearby mare, especially to the north and southwest. The rim is broken in the northwest by the small Cameron crater. The inner rim face lacks terraces, but in the interior is an unusual concentric inner rim that is heavily worn and irregular. This is a floor-fractured crater, possibly created by an uplift of mare material from beneath the interior. There is a low central peak complex in the middle of the relatively flat interior floor. There are also some slender rilles that are concentric to the rim.
The crater has a pair of faint dark patches. One patch is located just south of the central peak and the other falls on the sides of the northern rim near Cameron. These were likely created by deposits of volcanic ash from small vents. Taruntius has a ray system with a radius of over 300 kilometers, and is probably less than a billion years of age. April 2005. C9.25 @ F42. LU075M.
Thebit is an impact crater located on the southeast shore of Mare Nubium. To the southwest is the flooded remnants of Thebit P, which is actually larger in diameter than Thebit itself.. The rim of Thebit crater is generally circular in outline, with a double-notch in the southwest wall. A prominent bowl-shaped crater, Thebit A, lies across the west-northwestern rim. The west-northwestern rim of this crater is overlain in turn by the even smaller Thebit L. Together this forms an elegant arrangement that makes Thebit relatively simple to identify. The floor of Thebit crater is rough and has no central peak. The rim displays a terrace, and has a hilly outer rampart. 2006/04/08 & 20. C14 @ F41. LU075M.
Theophilus is a prominent impact crater that lies between Sinus Asperitatis in the north and Mare Nectaris to the southeast. It partially intrudes into the comparably-sized Cyrillus crater to the southwest.
The Rev. T. W. Webb described this as "the deepest of all visible craters". The rim of Theophilus crater has a wide, terraced inner surface that shows indications of landslips. The exterior has a wide, wrinkled rampart that descends about 1.4 kilometers to the surrounding maria. The largest impact crater of significance on the wall is the small Theophilus B on the inside of the northwest rim. Most of the rays from this crater have been weathered away, although a few are still visible.
The floor of the crater is relatively flat, and it has a large, triple-peaked central crater that climbs to a height of about 2 kilometers above the floor. The western peak is designated Psi (ψ), the eastern Phi (φ), and the northern peak is Alpha (α) Theophilus. The western slopes of this ridge are wider and more irregular, whereas the peaks descend more sharply to the floor on the northern and western faces. The Apollo 16 mission collected several pieces of basalt that are believed to be ejecta from the formation of the Theophilus crater. 2005/09/22 & 2007/03/27. C14 @ F41. LU075M.
Timocharis is a prominent impact crater located on the Mare Imbrium. The closest crater of comparable dimensions is Lambert to the west. The rim of Timocharis has a somewhat polygonal outline, with an outer rampart that extends over 20 kilometers in all directions. The interior wall is slumped and sharply terraced. The center of the floor is occupied by a craterlet that lies on a slight rise. This impact has almost completely removed the original central peak. The crater has a minor ray system that extends for over 130 km. 2006/10/14. C14 @ F41. LU075M.
Tranquility Base was the name given by Astronaut Neil Armstrong to the landing site on the moon where the Apollo 11 Lunar Module Eagle landed. The lunar coordinates of Tranquility Base are, which is located in the south-western corner of the lunar plain called the Mare Tranquillitatis (Sea of Tranquility ) Three small craters bearing the names of the crew of Apollo 11 lie to the north of the actual landing site. The landing site of the Surveyor 5 lunar probe is also marked. It land on September 11th, 1967 and transmitted over 19,000 images during its 65hrs of operation. 2005/12/20. C14 @ F41. LU075M.
Rimae Triesnecker. To the east of the Triesnecker crater is an extensive system of rilles extending over an area 200 kilometers across, running generally north-south. These were likely created by tectonic forces beneath the surface. Beyond, to the northeast, is the Rima Hyginus valley, with the Hyginus crater at the mid-point. 2007/03/26 & 27. C14 @ F42. SKYnyx 2.0M
Tycho is a very prominent impact crater located in the southern lunar highlands, named after Tycho Brahe. The surface around Tycho is replete with craters of various differing radii, many overlapping still older craters. Some of the smaller craters are secondary craters formed from larger chunks of ejecta from Tycho.
Tycho is a relatively young crater, with an estimated age of 108 million years, as estimated from samples of the crater rays recovered during the Apollo 17 mission. The crater is sharply defined and free of the wear that affects older craters. The interior has a high albedo that is prominent when the sun is overhead, and the crater is surrounded by a distinctive ray system forming long spokes that reach as long as 1,500 kilometers. Sections of these rays can be observed even when Tycho is only illuminated by earthlight.
The ramparts beyond the rim have a lower albedo than the interior for a distance of over a hundred kilometers, and are free of the ray markings that lie beyond. This darker rim may have been formed from minerals excavated during the impact.
Its inner wall is slumped and terraced, sloping down to a rough but nearly flat floor exhibiting small, knobby domes. The floor displays signs of past volcanism, most likely from rock melt caused by the impact. Detailed photographs of the floor show that it is covered in a criss-crossing array of cracks and small hills. The central peaks rise 1.6 kilometers above the floor, and a lesser peak stands just to the northeast of the primary massif.
Infrared observations of the lunar surface during an eclipse have demonstrated that Tycho cools at a slower rate than other parts of the surface, making the crater a "hot spot". This effect is caused by the difference in materials that cover the crater.
The rim of this crater was chosen as the target of the Surveyor 7 mission. The robotic spacecraft safely touched down north of the crater in January 1968. The craft performed chemical measurements of the surface, finding a composition different from the maria. From this one of the main components of the highlands was theorized to be anorthosite, an aluminium-rich mineral. The crater was also imaged in great detail by the Orbiter V.
From the 1950s through the 1990s, NASA aerodynamicist Dean Chapman and others advanced the "lunar origin" theory of tektites. Chapman used complex orbital computer models and extensive wind tunnel tests to support the theory that the so-called Australasian tektites originated from the Rosse ejecta ray of Tycho. Until the Rosse ray is sampled, a lunar origin for these tektites cannot be ruled out.
This crater was drawn on lunar maps as early as 1645, when Antonius Maria Schyrleus de Rheita depicted the bright ray system. 2006/04/08, 09, 19, & 20. C14 @ F41. LU075M.
Vieta is an impact crater that lies due north of the Schickard walled plain, in the southwestern part of the Moon. The outer rim of Vieta has undergone some impact erosion, and small craters lie along the northeast, south, and north-northwestern sides. The inner walls are irregular, with incised bases in some locations. A chain of small craters lies across the northern half of the interior floor, following a line toward the east-northeast. The floor is nearly level, but with some uneven areas in the south and by the crater chain. 2006/11/04 & 2006/04/12. C14 @ F41. LU075M.
Vitello lies along the southern edge of the small Mare Humorum, in the southwest part of the Moon's near side. This crater has a low, roughly circular rim with a sharp edge. The interior floor of Vitello is irregular, rugged and hilly, with a smaller, concentric crater offset to the east of the mid-point. A low ridge projects out from the northwest rim into the mare. 2006/04/10. C14 @ F41. LU075M.
Vlacq is a prominent impact crater that is located in the southeastern part of the Moon, and appears foreshortened when viewed from the Earth. Vlacq has become eroded, but not to the degree of the larger neighboring craters. The satellite crater 'Vlacq G' is intruding into the southern rim of Vlacq, and is overlaid in turn along the southwest rim by the sharp-rimmed 'Vlacq B'. The satellite crater 'Vlacq C' is attached to the northeastern exterior rim of Vlacq.
The interior floor of Vlacq crater has been resurfaced by lava, leaving a nearly level base. The southwest half of the floor, however, is overlaid by ejecta from nearby impacts. In the mid-point of the floor is a rounded massif that is about 15 kilometers in length, being long along the northwest direction. The floor contains a number of tiny craterlets as well as several ghostly crater remnants in the western half. The most notable of these is a circular depression to the west of the central peak. 2005/11/20. C14 @ F41. LU075M.
Walter is an ancient impact crater located in the southern highland region of the Moon. It is joined along the western rim to the Deslandres crater. The rim of Walter is complex, heavily eroded and incised by lesser impacts. The wall retains a generally circular form, but many of its features have been worn away and there is a slight protruding bulge in the western rim. The floor has been resurfaced after the original impact, leaving the southwest half relatively smooth. In the northwest quadrant is an offset central peak that has been worn and impacted by several small crater. 2006/04/19. C14 @ F41. LU075M.
Wilhelm is located in the southern part of the Moon, to the west of the prominent Tycho crater. Portions of the ray material from Tycho lay across the rim and floor of Wilhelm. Attached to the southern rim is the Montanari crater, while Lagalla crater is attached to the southwest.
This crater formation is of the type termed a walled plain. It has a heavily eroded outer rim that is overlaid by several smaller craters. Among these are the 'Wilhelm A' and 'Wilhelm K' crater pair across the southwest rim, and 'Wilhelm B' just to the northwest along the western rim. 'Wilhelm C' is intruding into the north-northeast rim, and 'Wilhelm D' is attached to the northeast outer rim. There is an outward protrusion in the southern rim that extends to contact Montanari crater. The interior floor of Wilhelm is relatively level, with a relatively rough area to the northeast. The remainder is flat and almost featureless except for a few tiny craterlets. 2006/04/09 & 2006/04/21. C14 @ F41. LU075M.
Wurzelbauer is the remnant of a lunar crater. It is located in the rugged terrain on the Moon's southern hemisphere. The slightly smaller Gauricus crater lies next to the eastern rim, while to the north-northeast is the Pitatus crater. The rim of this crater has been deeply eroded, and now forms a low, somewhat irregular ridge around the interior floor. Along the southeastern rim is the 'Wurzelbauer B' crater, while 'Wurzelbauer A' is nearly attached to the southern rim. A short chain of craters lies across the northern rim.
The western half of the interior floor is somewhat more irregular than in the east, with a complex of low ridges covering parts of the surface. The western edge of the floor is marked by a section of the ray system radiating from Tycho crater to the south-southeast. 2006/04/21. C14 @ F41. LU075M.
Xenophanes is located along the northwestern limb of the Moon. It is nearly attached to Volta crater, a similar formation to the south-southwest. This crater is significantly foreshortened when viewed from the Earth, hindering observation. This is a worn and eroded crater with a battered outer rim that is overlaid by several smaller craters. The rim is a circular range of rugged, irregular ground that is notched in places along the inner wall. A chain of small craters lies along the northern and northeastern rim. At the west end, a pair of clefts in the rim nearly join the floor to the surface beyond. To the northeast, 'Xenophanes A' is an impact crater with a sharp rim and a rough interior.
The interior surface is irregular, but sections have been resurfaced by basaltic-lava. A pair of flooded crater rims lie along the southern and northeast sections of the interior. The interior is more level and less rough at the eastern end. 2006/04/13. C14 @ F41. LU075M.
Zach is a lunar impact crater located in the heavily-cratered southern sector of the moon. Due to foreshortening, the crater has an oblong appearance when viewed from Earth. The inner walls of Zach are prominently terraced, while parts of the outer wall are indented by lesser craters. There are adjacent craters attached to the northeast, southwest, and southern parts of the rim. There is also a pair of overlapping craters on the northwest rim. The bottom is relatively flat with a few craterlets and a double central peak offset to the north. 2006/04/19. C14 @ F41. LU075M.
Zucchius is a prominent impact crater located near the southwest limb. Because of its location the crater appears oblong-shaped due to foreshortening. It lies northeast of the much larger Bailly walled-plain. Zucchius's rim is symmetrical and shows little significant wear from impacts. The inner wall is terraced, and there is a group of small central peaks that forms a curving arc around the middle of the floor. This crater is believed to have formed during the Copernician period, within the last 1.2 billion years. 2006/04/11 & 12. 2006/11/04. C14 @ F41. LU075M.
© All images copyright Damian Peach. No images used on this page may be used. amended, or distributed without the consent of the author.