Rima Ariadaeus is a linear rille on the lunar surface, situated at coordinates 6°24′N14°00′E / 6.4°N 14.0°E . Measuring approximately 5 km (3.1 mi) in width and spanning a length of 300 km (186.4 mi), it stretches between Mare Tranquillitatis and Mare Vaporum. [1] [2]
Some scientists think that the linear rilles might have formed after large impact events, while others believe that the rilles were formed as a surface manifestation of deep-seated dike systems when the Moon was still volcanically active. Rima Ariadaeus is thought to have been formed when a section of the Moon's crust sank down between two parallel fault lines (making it a graben or fault trough). [3] Rima Ariadaeus shows no trace of associated volcanism and is thus considered to be an end member of the sequence where only pure faulting is involved i.e. a linear rille. [4]
The ridges crossing the rille trough of Rima Ariadaeus and the surrounding plains units have been offset by the trough, proving that the ridges are older than the faults. Some craters are cut off by the faults and are, therefore, older. Other craters lie on the wall of the trough and are younger than the faulting. The faulting must be relatively young because so few craters appear to be younger than the faults, and because the edges of the trough appear to be crisp and little affected by slumping and other mass wasting. [4]
An Apollo mission photograph of this 300-kilometer-long rille has been used as evidence in a claim circulating in the Muslim online community, asserting that the Islamic account of the splitting of the moon is real. Astronomer Paul Groot of Radboud University, however, refutes this claim, pointing out that the rille does not encircle the entire surface of the moon and arguing that its formation is related to the impact that formed the Tycho crater, which is located to the lower right of the feature in the orientation of the photo. NASA notes that the rille is similar to geological faults on Earth and states, "No current scientific evidence reports that the Moon was split into two (or more) parts and then reassembled at any point in the past." [5] [6]
Rille is typically used to describe any of the long, narrow depressions in the surface of the Moon that resemble channels. The Latin term is rima, plural rimae. Typically, a rille can be several kilometers wide and hundreds of kilometers in length. However, the term has also been used loosely to describe similar structures on a number of planets in the Solar System, including Mars, Venus, and on a number of moons. All bear a structural resemblance to each other.
Posidonius is a lunar impact crater that is located on the north-eastern edge of Mare Serenitatis, to the south of Lacus Somniorum. It was named after ancient Greek philosopher and geographer Posidonius of Apamea. The crater Chacornac is attached to the southeast rim, and to the north is Daniell.
Hyginus is a lunar caldera located at the east end of the Sinus Medii. It was named after ancient Roman astronomer Gaius Julius Hyginus. Its rim is split by a 220 kilometer-long rille, Rima Hyginus, that branches to the northwest and to the east-southeast. The crater is deeper than the rille, and lies at intersection of the rille's branches. Together, the crater and the rille form a prominent feature in an otherwise flat surface. Smaller craters along the length of the rille may have been caused by the collapse of an underlying structure.
Cauchy is a small lunar impact crater on the eastern Mare Tranquillitatis. It was named after French mathematician Augustin-Louis Cauchy. It is circular and symmetric, with a small interior floor at the midpoint of the sloping inner walls. Due to the high albedo of this bowl-shaped formation, it is particularly prominent at full Moon.
Bode is a small crater located near the central region of the Moon, to the northwest of the joined craters Pallas and Murchison. It lies on a region of raised surface between the Mare Vaporum to the northeast, Sinus Aestuum to the west, and Sinus Medii to the southeast. The crater was named after German astronomer Johann Elert Bode.
Triesnecker is a prominent lunar impact crater that is located in the Sinus Medii, near the central part of the Moon's near side. Its diameter is 25 km. It was named after Austrian astronomer Franz de Paula Triesnecker. It is located to the north-northwest of the crater Rhaeticus, and to the east-southeast of the flooded Murchison.
Ariadaeus is a small, bowl-shaped lunar impact crater on the western shores of Mare Tranquillitatis. It lies to the north of the crater Dionysius, and to the west-southwest of Arago. The crater is joined along the northeast rim by the slightly smaller Ariadaeus A, and the two form a double-crater. Its diameter is 10.4 km.
Cardanus is a lunar impact crater that is located in the western part of the Moon, in the western part of the Oceanus Procellarum. Due to its location the crater appears very oval because of foreshortening, and it is viewed almost from the side.
Delisle is a small lunar impact crater in the western part of the Mare Imbrium. It was named after French astronomer Joseph-Nicolas Delisle. It lies to the north of the crater Diophantus, and just to the northwest of the ridge designated Mons Delisle. Between Delisle and Diophantus is a sinuous rille named Rima Diophantus, with a diameter of 150 km. To the northeast is another rille designated Rima Delisle, named after this crater.
Réaumur is the remains of a lunar impact crater located on the southern edge of Sinus Medii. Its diameter is 51 km. It was named after the 18th century French scientist René de Réaumur. It shares an eroded rim with the similar crater Oppolzer to the northwest. It lies to the northwest of the large walled plain Hipparchus, and east of Flammarion. To the south is Gyldén, and farther to the south-southwest is Ptolemaeus.
Silberschlag is a small, circular Impact crater in the central portion of the Moon. It was named after German astronomer Johann Silberschlag. It lies between the craters Agrippa to the southwest and Julius Caesar to the northeast. Silberschlag is bowl-shaped and is joined at the northern rim by a small ridge.
Whewell is a lunar impact crater that lies on a stretch of lava-resurfaced terrain to the west of Mare Tranquillitatis. Its diameter is 13 km. It was named after the 19th-century English philosopher and naturalist, William Whewell. It is located to the east of the disintegrated crater Tempel and north-northwest of D'Arrest. To the east is Cayley, a slightly larger but very similar formation. To the North lies the Rima Ariadaeus, which is a linear rille that is 300 kilometers long and was formed when a section of the Moon's crust sank down between two parallel fault lines, producing a graben. Further north again, lies the 90 km wide crater Julius Caesar.
Capuanus is a lunar impact crater that lies along the southern edge of the Palus Epidemiarum. It was named after Italian astronomer F. Capuano di Manfredonia. 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. Dotting the floor of the crater are a number of domes, which are believed to have formed through volcanic activity.
Sinus Medii is a small lunar mare. It takes its name from its location at the intersection of the Moon's equator and prime meridian; as seen from the Earth, this feature is located in the central part of the Moon's near side, and it is the point closest to the Earth. From this spot, the Earth would always appear directly overhead, although the planet's position would vary slightly due to libration.
Rupes Recta is a linear fault on the Moon, in the southeastern part of the Mare Nubium at 22.1°S 7.8°W. The name is Latin for straight cliff, although it is more commonly called the Straight Wall. This is the most well-known escarpment on the Moon, and is a popular target for amateur astronomers.
Palus Epidemiarum is a small lunar mare in the southwestern part of the Moon's near side. This feature forms a rough band of lava-flooded terrain that runs generally west–east, with a northward extension near the western end. It spans a shallow trough extending 300 by 120 km. The average thickness of the basalt is 200–250 m, with a maximum depth of 750 m. The feature lies to the southwest of Mare Nubium, and southeast of Mare Humorum.
Lacus Mortis is a hexagonal-shaped plain of basaltic lava flows in the northeastern part of the Moon's near face. It was formed as a floor-fractured crater during the pre-Imbrian epoch, then flooded during the late Imbrian period. This feature lies just to the south of the elongated Mare Frigoris, being separated by a slender arm of rugged ground and linked at the eastern extreme. To the south is the Lacus Somniorum, separated from this mare by the joined craters Plana and Mason, and a strip of uneven surface.
The geology of the Moon is quite different from that of Earth. The Moon lacks a true atmosphere, and the absence of free oxygen and water eliminates erosion due to weather. Instead, the surface is eroded much more slowly through the bombardment of the lunar surface by micrometeorites. It does not have any known form of plate tectonics, it has a lower gravity, and because of its small size, it cooled faster. In addition to impacts, the geomorphology of the lunar surface has been shaped by volcanism, which is now thought to have ended less than 50 million years ago. The Moon is a differentiated body, with a crust, mantle, and core.
Hadley–Apennine is a region on the near side of Earth's Moon that served as the landing site for the American Apollo 15 mission, the fourth crewed landing on the Moon and the first of the "J-missions", in July 1971. The site is located on the eastern edge of Mare Imbrium on a lava plain known as Palus Putredinis. Hadley–Apennine is bordered by the Montes Apenninus, a mountain range, and Hadley Rille, a meandering channel, on the east and west, respectively.
Volcanism on the Moon is represented by the presence of volcanoes, pyroclastic deposits and vast lava plains on the lunar surface. The volcanoes are typically in the form of small domes and cones that form large volcanic complexes and isolated edifices. Calderas, large-scale collapse features generally formed late in a volcanic eruptive episode, are exceptionally rare on the Moon. Lunar pyroclastic deposits are the result of lava fountain eruptions from volatile-laden basaltic magmas rapidly ascending from deep mantle sources and erupting as a spray of magma, forming tiny glass beads. However, pyroclastic deposits formed by less common non-basaltic explosive eruptions are also thought to exist on the Moon. Lunar lava plains cover large swaths of the Moon's surface and consist mainly of voluminous basaltic flows. They contain a number of volcanic features related to the cooling of lava, including lava tubes, rilles and wrinkle ridges.
Experts agree that Rima Ariadaeus, about 300 km (186.4 mi) long, is a fault system similar to those on Earth.