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28-574: Mare Australe / ɔː ˈ s t r eɪ l iː / (Latin austrāle the " Southern Sea ") is a lunar mare located in the southeastern hemisphere of the Moon . It is 997 kilometers in diameter, overlapping the near and far sides of the Moon. Smooth, dark volcanic basalt lines the bottom of the mare. The Australe basin was formed in the Pre-Nectarian epoch , while the mare material inside formed in

56-591: A map of the Moon that names Mare Imbrium "Regio Magna Orientalis" (the Large Eastern Region). Michael van Langren 's 1645 map named it "Mare Austriacum" (the Austrian Sea). Mare Imbrium is visible to the naked eye from Earth. In the traditional ' Man in the Moon ' image seen on the Moon in Western folklore, Mare Imbrium forms the man's right eye. On 17 November 1970 at 03:47 Universal Time,

84-550: Is submerged under the mare's basalt, resulting in only isolated peaks remaining in some areas, such as Mons Pico and Mons La Hire . Numerous estimates of the depth of the mare material have been made using various methods. These include analyses of gravity, seismic, and radar data; studies of craters partially filled with basalt and those that have completely penetrated the mare; and comparisons of lunar basins filled with mare deposits to unfilled basins. These studies have yielded depth estimates ranging from 2 km to 5 km in

112-606: Is surrounded by three concentric rings of mountains, uplifted by the colossal impact event that excavated it. The outermost ring of mountains has a diameter of 1300 km and is divided into several different ranges; the Montes Carpatus to the south, the Montes Apenninus to the southeast, and the Montes Caucasus to the east. At their highest, the outer ring of mountains rise more than 5 km above

140-411: Is the near-total absence of water in any form in the lunar basalts. Lunar basalts do not contain hydrogen-bearing minerals like the amphiboles and phyllosilicates that are common in terrestrial basalts due to alteration or metamorphism. Mare Imbrium Mare Imbrium / ˈ ɪ m b r i ə m / ( Latin imbrium , the " Sea of Showers " or " Sea of Rains ") is a vast lava plain within

168-542: The Apennine Mountains . Commander David Scott and Lunar Module Pilot James Irwin spent three days on the surface of the Moon, including 18½ hours outside the spacecraft on lunar extra-vehicular activity . Command Module Pilot Alfred Worden remained in orbit and acquired hundreds of high-resolution photographs of Mare Imbrium (and other regions of the Moon) as well as other types of scientific data. The crew on

196-606: The Procellarum KREEP Terrane . While the enhancement in heat production within the Procellarum KREEP Terrane is most certainly related to the longevity and intensity of volcanism found there, the mechanism by which KREEP became concentrated within this region is not agreed upon. Using terrestrial classification schemes, all mare basalts are classified as tholeiitic , but specific subclassifications have been invented to further describe

224-539: The Upper Imbrian epoch. The basin was almost completely destroyed by impacts prior to the appearance of the mare. Unlike most of the lunar maria, Mare Australe has an uneven surface that is marked by a number of crater impacts. Examples of these include the craters Jenner and Lamb , which are flooded with basaltic lava much like many of the other crater features in this mare. The selenographic coordinates of this mare are 38.9° S, 93.0° E. The eastern half of

252-610: The Imbrium Basin on the Moon and is one of the larger craters in the Solar System . The Imbrium Basin formed from the collision of a proto-planet during the Late Heavy Bombardment . Basaltic lava later flooded the giant crater to form the flat volcanic plain seen today. The basin's age has been estimated using uranium–lead dating methods to approximately 3.9 billion years ago, and the diameter of

280-417: The Moon's entire lithosphere . At the region of the Moon's surface exactly opposite Imbrium Basin, there is a region of chaotic terrain (the crater Van de Graaff ) which is thought to have been formed when the seismic waves of the impact were focused there after travelling through the Moon's interior. Mare Imbrium is about 750 miles (1,210 km) wide. A mass concentration (mascon), or gravitational high,

308-477: The Moon's surface by large projectiles blasted out of the basin at low angles, causing them to skim across the lunar surface ploughing out these features. The sculpture pattern was first identified by Grove Karl Gilbert in 1893. Furthermore, a Moon-wide pattern of faults which run both radial to and concentric to the Imbrium basin were thought to have been formed by the Imbrium impact; the event literally shattered

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336-507: The Soviet spacecraft Luna 17 made a soft landing in the mare, at latitude 38.28 N, and longitude 35.00 W. Luna 17 carried Lunokhod 1 , the first robotic rover to be deployed on the Moon or any extraterrestrial body. Lunokhod 1, a remote-controlled rover, was successfully deployed and undertook a mission lasting several months. In 1971, the crewed Apollo 15 mission landed in the southeastern region of Mare Imbrium, between Hadley Rille and

364-504: The Yutu rover 7 hours and 24 minutes later. Chang'e 3 mission attempted to perform the first direct measurement of the structure and depth of the lunar soil down to a depth of 30 m (98 ft), and investigate the lunar crust structure down to several hundred meters deep. The rover's ground penetrating radar found evidence of at least nine distinct rock layers , indicating that the area had surprisingly complex geological processes and

392-455: The asteroid belt collided with the Moon during the Late Heavy Bombardment . The impact is dated to approximately 3922 ± 12 million years ago, based on radiometric dating techniques. Ejecta from the impact covers large areas of the near side of the Moon. With a diameter of 1145 km, Mare Imbrium is second only to Oceanus Procellarum in size among the maria, and it is the largest mare associated with an impact basin. The Imbrium Basin

420-457: The central part of the mare. It is thought that the original crater left by the Imbrium impact was as much as 100 km deep, but that the floor of the basin bounced back upwards immediately afterwards. Surrounding the Imbrium Basin is a region blanketed by ejecta from the impact, extending roughly 800 km outward. Also encircling the basin is a pattern of radial grooves called the "Imbrium Sculpture", which have been interpreted as furrows cut in

448-482: The far side are old, whereas the youngest flows are found within Oceanus Procellarum on the nearside. While many of the basalts either erupted within, or flowed into, low-lying impact basins, the largest expanse of volcanic units, Oceanus Procellarum, does not correspond to any known impact basin. There are many common misconceptions concerning the spatial distribution of mare basalts. The reason that

476-609: The final nomenclature, that of states of mind, was accepted, and do not follow this pattern. When Mare Moscoviense was discovered by the Luna 3 , and the name was proposed by the Soviet Union, it was only accepted by the International Astronomical Union with the justification that Moscow is a state of mind. The ages of the mare basalts have been determined both by direct radiometric dating and by

504-451: The high-titanium concentrations are the least abundant. TiO 2 abundances can reach up to 15 wt.% for mare basalts, whereas most terrestrial basalts have abundances much less than 4 wt.%. A special group of lunar basalts is the KREEP basalts, which are abnormally rich in potassium (K), rare-earth elements (REE), and phosphorus (P). A major difference between terrestrial and lunar basalts

532-411: The impactor has been estimated to be 250 ± 25 km. The Moon's maria (plural of mare ) have fewer features than other areas of the Moon because molten lava pooled in the craters and formed a relatively smooth surface. Mare Imbrium is not as flat as it would have originally been when it first formed as a result of later events that have altered its surface. Mare Imbrium formed when a proto-planet from

560-554: The mare basalts are predominantly located on the near-side hemisphere of the Moon is still being debated by the scientific community. Based on data obtained from the Lunar Prospector mission, it appears that a large proportion of the Moon's inventory of heat producing elements (in the form of KREEP ) is located within the regions of Oceanus Procellarum and the Imbrium basin , a unique geochemical province now referred to as

588-687: The mare lies on the far side of the Moon , although it can be viewed in its entirety during periods of favorable libration . This article related to the Moon is a stub . You can help Misplaced Pages by expanding it . Lunar mare The names of maria refer to sea features ( Mare Humorum , Mare Imbrium , Mare Insularum , Mare Nubium , Mare Spumans , Mare Undarum , Mare Vaporum , Oceanus Procellarum , Mare Frigoris ), sea attributes ( Mare Australe , Mare Orientale , Mare Cognitum , Mare Marginis ), or states of mind ( Mare Crisium , Mare Ingenii , Mare Serenitatis , Mare Tranquillitatis ). Mare Humboldtianum and Mare Smythii were established before

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616-503: The mare may be "The Shrine of Hecate "; Plutarch records that the Ancient Greeks gave this name to the largest of the "hollows and deeps" on the Moon, believing it to be the place where the souls of the deceased were tormented. Ewen A. Whitaker argues that this likely refers to Mare Imbrium, "the largest regular-shaped dark area unbroken by bright patches" that can be seen with the naked eye. Around 1600, William Gilbert made

644-543: The population of lunar basalts. Mare basalts are generally grouped into three series based on their major element chemistry: high-Ti basalts , low-Ti basalts , and very-low-Ti (VLT) basalts . While these groups were once thought to be distinct based on the Apollo samples, global remote sensing data from the Clementine mission now shows that there is a continuum of titanium concentrations between these end members, and that

672-510: The rille wall. On 17 March 2013, an object hit the lunar surface in Mare Imbrium and exploded in a flash of apparent magnitude 4. The resulting crater was 18 meters wide. This was the brightest impact recorded since NASA's lunar impact team began monitoring in 2005. Chang'e 3 landed on 14 December 2013 on Mare Imbrium, about 40 km south of the 6 km diameter Laplace F crater, at 44.1260°N 19.5014°W. The lander deployed

700-429: The surface explored the area using the first lunar rover and returned to Earth with 77 kilograms (170 lb) of lunar surface material. Samples were collected from Mons Hadley Delta , believed to be a fault block of pre-Imbrian ( Nectarian or Pre-Nectarian ) lunar crust, including the " Genesis Rock ." This was also the only Apollo mission to visit a lunar rille, and to observe outcrops of lunar bedrock visible in

728-482: The surface of Mare Imbrium. The ring mountains are not as well developed to the north and west, and it appears they were simply not raised as high in these regions by the Imbrium impact. The middle ring of mountains forms the Montes Alpes and Montes Archimedes . The innermost ring, with a diameter of 650 km, is defined by Montes Recti , Montes Teneriffe , and possibly Montes Spitzbergen . Much of this ring

756-519: The technique of crater counting . The radiometric ages range from about 3.16 to 4.2 billion years old (Ga), whereas the youngest ages determined from crater counting are about 1.2 Ga. Updated measurements of samples collected by the Chang’e-5 mission show that some lunar basalts could be as young as 2.03 billion years old. Nevertheless, the majority of mare basalts appear to have erupted between about 3 and 3.5 Ga. The few basaltic eruptions that occurred on

784-451: Was identified in the center of Mare Imbrium from Doppler tracking of the five Lunar Orbiter spacecraft in 1968. The Imbrium mascon is the largest on the Moon. It was confirmed and mapped at higher resolution with later orbiters such as Lunar Prospector and GRAIL . Like most of the other maria on the Moon, Mare Imbrium was named by Giovanni Riccioli , whose 1651 nomenclature system has become standardized. The earliest known name for

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