1.
Lunar mare
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The lunar maria /ˈmɑːriə/ are large, dark, basaltic plains on Earths Moon, formed by ancient volcanic eruptions. They were dubbed maria, Latin for seas, by astronomers who mistook them for actual seas. They are less reflective than the highlands as a result of their iron-rich compositions, the maria cover about 16 percent of the lunar surface, mostly on the side visible from Earth. The few maria on the far side are smaller, residing mostly in very large craters. The traditional nomenclature for the Moon also includes one oceanus, as well as features with the names lacus, palus, the last three are smaller than maria, but have the same nature and characteristics. The names of maria generally refer to states of mind, with a few exceptions, for example, Mare Humboldtianum and Mare Smythii were established long before the nomenclature was accepted and do not follow this pattern. The ages of the mare basalts have been determined both by direct radiometric dating and by the technique of crater counting, the few basaltic eruptions that occurred on 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, there are many common misconceptions concerning the spatial distribution of mare basalts. Since many mare basalts fill low-lying impact basins, it was assumed that the impact event itself somehow caused the volcanic eruption. It is sometimes suggested that the gravity field of the Earth might preferentially allow eruptions to occur on the near side, but not far side. However, in a frame rotating with the Moon, the centrifugal acceleration the moon is experiencing is exactly equal. There is thus no net force directed towards the Earth, the Earth tides do act to deform the shape of the Moon, but this shape is one of an elongated ellipsoid with high points at both the sub- and anti-Earth points. As an analogy, one should remember that there are two high tides per day on Earth, and not one, since mare basaltic magmas are denser than upper crustal anorthositic materials, basaltic eruptions might be favored at locations of low elevation where the crust is thin. However, the far side South Pole-Aitken basin contains the lowest elevations of the Moon and is yet only modestly filled by basaltic lavas, in addition, the crustal thickness beneath this basin is predicted to be much smaller than beneath Oceanus Procellarum. It is commonly suggested that there is form of link between the synchronous rotation of the Moon about the Earth, and the mare basalts. However, gravitational torques that result in tidal despinning only arise from the moments of inertia of the body, furthermore, tidal despinning is predicted to have occurred quickly, whereas the majority of mare basalts erupted about one billion years later. The reason that the basalts are predominantly located on the near-side hemisphere of the Moon is still being debated by the scientific community. In this low-impact collision, the moon was crushed into the surface of the moon
2.
Far side of the Moon
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The far side of the Moon is the hemisphere of the Moon that always faces away from Earth. The far sides terrain is rugged, with a multitude of impact craters and it has one of the largest craters in the Solar System, the South Pole–Aitken basin. About 18 percent of the far side is visible from Earth due to libration. The remaining 82 percent remained unobserved until 1959, when the Soviet Unions Luna 3 space probe photographed it, the Soviet Academy of Sciences published the first atlas of the far side in 1960. In 1968, the Apollo 8 missions astronauts were the first humans to view this region directly when they orbited the Moon, to date, no human being has ever stood on the surface of the far side of the Moon. Astronomers have suggested installing a large telescope on the far side. Tidal forces from Earth have slowed down the Moons rotation so that the side is always facing the Earth. The other face, most of which is never visible from the Earth, is called the far side of the Moon. Over time some parts of the far side can be due to libration. In total 59 percent of the Moons surface is visible from Earth at one time or another, useful observation of the parts of the far side of the Moon occasionally visible from Earth is difficult because of the low viewing angle from Earth. While many misconstrue this to think that the dark side receives little to no sunlight, in reality, however, the near side also receives sunlight reflected from the Earth, known as earthshine. Earthshine does not reach the area of the far side which cannot be seen from Earth, only during a full moon is the whole far side of the Moon dark. The word dark has expanded to refer to the fact that communication with spacecraft can be blocked while on the far side of the Moon. The two hemispheres have distinctly different appearances, with the near side covered in multiple, large maria, the far side has a battered, densely cratered appearance with few maria. Only 1% of the surface of the far side is covered by maria and it has also been proposed that the differences between the two hemispheres may have been caused by a collision with a smaller companion moon that also originated from the Theia collision. The far side has more visible craters and this was thought to be a result of the effects of lunar lava flows, which cover and obscure craters, rather than a shielding effect from the Earth. NASA calculates that the Earth obscures only about 4 square degrees out of 41,000 square degrees of the sky as seen from the Moon and this makes the Earth negligible as a shield for the Moon. Newer research suggests that the reason the side of the moon facing Earth has fewer impact craters is heat from Earth at the time when the Moon was formed, the lunar crust consists primarily of plagioclases formed when aluminium and calcium condensed and combined with silicates in the mantle
3.
Mare Marginis
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Mare Marginis is a lunar mare that lies on the very edge of the lunar nearside. The selenographic coordinates of this feature are 13. 3° N,86. 1° E, the name is Latin for Sea of the Edge. This mare differs from most of the maria, it has an irregular outline. It has small circular and elongated features in the plains that probably mark impact craters buried by less than 1000 to 1700 feet of lava. Further, Mare Marginis is not centered on any clear, large impact basin, thus, Mare Marginis seems to mark a low-lying region of the highlands where mare lavas were just able to reach the surface. Several large mare-floored craters also occur nearby, in these craters, the crater floors lie below the surrounding highland surface. Thus, they mark sites around Mare Marginis where lavas were close to the lunar surface, the major crater to the north of Marginis is Al-Biruni, with Ibn Yunus to the southeast and Goddard to the northwest. The surface of this mare displays some swirling, higher albedo deposits that are similar to the Reiner Gamma feature on the Oceanus Procellarum and this feature is associated with a relatively strong magnetic field. It is also located at the antipode of the Mare Orientale impact basin, other possible explanations for the formation include a cometary impact, venting of volcanic gases, or just normal surface markings that are shielded from space weathering due to the magnetic field. But the exact cause of albedo features such as this remain a mystery for future solution, paul D. Spudis, The Once and Future Moon, Smithsonian Institution Press,1996, ISBN 1-56098-634-4
4.
Korolev (lunar crater)
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Korolev is a large lunar crater of the walled plain or basin type, named for Soviet rocket engineer Sergey Korolyov. It lies on the far side of the Moon, and the part of its floor crosses the lunar equator. Notable nearby craters include Galois just to the southeast, Das to the south-southeast, Doppler attached to the southern rim, rays of the crater Crookes cover parts of the basin. The outer rim of Korolev is heavily worn and eroded, with a multitude of small craters lying across the wide rim, the interior floor is relatively flat compared to the surrounding terrain, but is pock-marked with many craters of varying sizes. The most notable of these craters are Korolev M in the southern part of the floor. Within the interior of Korolev is the remains of a second and this is roughly half the diameter of the outer wall, and is the most intact in the eastern half. Here it forms an arc of ridges across the floor. At the midpoint of the formation, there is nothing resembling a central peak, however the craters Korolev B, Korolev T, and Korolev L lie within the diameter of the inner ring. A small crater to the southwest of Korolev L was a control point, CP-1. Measurements taken from orbit on this point improved the accuracy of mapping of the far side. Until formal naming in 1970 by the IAU, the crater was known as Basin XV, Korolev lies to the south of the similar-sized Dirichlet-Jackson Basin. By convention these features are identified on maps by placing the letter on the side of the crater midpoint that is closest to Korolev
5.
Freundlich-Sharonov Basin
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The Freundlich-Sharonov Basin is a Pre-Nectarian impact basin on the far side of the moon. It is named after the younger craters Freundlich near the northwest margin and it lies east of Mare Moscoviense basin and northwest of Korolev basin. The basin is not obvious on lunar photographs, although it was discovered from analysis of Lunar Orbiter photographs, at the center is the small mare Lacus Luxuriae, just south of the oblique crater Buys-Ballot. Also at the center is a concentration, or gravitational high. The mascon was first identified by Doppler tracking of the Lunar Prospector spacecraft, other craters within the basin include Anderson, Virtanen, Zernike, Dante, and the smaller Šafařík. Morse and Spencer Jones are at the margins
6.
Gravity Recovery and Interior Laboratory
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The two small spacecraft GRAIL A and GRAIL B were launched on 10 September 2011 aboard a single launch vehicle, the most-powerful configuration of a Delta II, the 7920H-10. GRAIL A separated from the rocket about nine minutes after launch and they arrived at their orbits around the Moon 25 hours apart. The first probe entered orbit on 31 December 2011 and the second followed on 1 January 2012, the two spacecraft impacted the Lunar surface on December 17,2012. Maria Zuber of the Massachusetts Institute of Technology is GRAILs principal investigator, nASAs Jet Propulsion Laboratory manages the project. As of August 5,2011, the program has cost US$496 million, upon launch the spacecraft were named GRAIL A and GRAIL B and a contest was opened to school children to select names. Nearly 900 classrooms from 45 states, Puerto Rico and the District of Columbia, the winning names, Ebb and Flow, were suggested by 4th grade students at Emily Dickinson Elementary School in Bozeman, Montana. Each spacecraft transmitted and received telemetry from the spacecraft and Earth-based facilities. By measuring the change in distance between the two spacecraft, the gravity field and geological structure of the Moon was obtained, the two spacecraft were able to detect very small changes in the distance between one another. Changes in distance as small as one micron were detectable and measurable, the gravitational field of the Moon was mapped in unprecedented detail. A second phase, at an altitude, of data collection began 31 Aug 2012. On 5 Dec 2012 NASA released a gravity map of the Moon made from GRAIL data, the knowledge acquired will aid understanding of the evolutionary history of the terrestrial planets and computations of lunar orbits. Ka band Lunar Gravity Ranging System, derived from the Gravity Recovery, 90% of the GRACE software was reused for GRAIL. Radio science beacon Moon Knowledge Acquired by Middle school students, each MoonKAM system consists of a digital video controller and four camera heads. Click here for a MoonKAM photo from lunar orbit, thrusters aboard each spacecraft were capable of producing 22 newtons. The propulsion subsystem consisted of a fuel tank and a Re-repressurization system which were activated shortly after lunar orbit insertion. The very tight tolerances in the plan left little room for error correction leading to a launch window lasting one second. The primary science phase of GRAIL lasted for 88 days, from 7 Mar 2012 to 29 May 2012 and it was followed by a second science phase starting on 8 Aug. The gravity mapping technique was similar to that used by Gravity Recovery and Climate Experiment, the orbital insertion dates were December 31,2011 and January 1,2012
7.
Apollo 13
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Apollo 13 was the seventh manned mission in the American Apollo space program and the third intended to land on the Moon. The mission was commanded by James A. Lovell with John L. Jack Swigert as Command Module Pilot, Swigert was a late replacement for the original CM pilot Ken Mattingly, who was grounded by the flight surgeon after exposure to German measles. The story of the Apollo 13 mission has been dramatized multiple times and that crew was composed of L. Gordon Cooper, Jr, Donn F. Eisele, Edgar D. Mitchell. Deke Slayton, NASAs Director of Flight Crew Operations, never intended to rotate Cooper and Eisele to another mission and he assigned them to the backup crew simply because of a lack of flight-qualified manpower in the Astronaut Office at the time the assignment needed to be made. Slayton felt Cooper had no more than a small chance of receiving the Apollo 13 command, if he did an outstanding job with the assignment. Thus, the original assignment Slayton submitted to his superiors for this flight was, shepard, Jr, Stuart A. Roosa, Edgar D. Mitchell. Seven days before launch, the Backup Lunar Module Pilot, Charlie Duke and this exposed both the prime and backup crews, who trained together. Mattingly was found to be the one of the other five who had not had rubella as a child. Three days before launch, at the insistence of the Flight Surgeon, Mattingly never contracted rubella and was assigned after the mission as Command Module Pilot to Youngs crew, which later flew Apollo 16, the fifth mission to land on the Moon. Vance D. Brand, Jack R. Lousma, Joseph P. Kerwin, Gene Kranz – White Team, Glynn Lunney – Black Team, Milt Windler – Maroon Team, Gerry Griffin – Gold Team. The astronauts mission insignia was sculpted as a medallion titled Steeds of Apollo by Lumen Martin Winter and was struck by the Franklin Mint. Mass, CSM Odyssey 63,470 pounds, LM Aquarius 33,490 pounds, Perigee,99.3 nautical miles, Apogee,100.3 nautical miles, Inclination,31. 817°, Period,88.19 min. The Apollo 13 mission was to explore the Fra Mauro formation, or Fra Mauro highlands and it is a widespread, hilly selenological area thought to be composed of ejecta from the impact that formed Mare Imbrium. The next Apollo mission, Apollo 14, eventually made a flight to Fra Mauro. April 14,1970 UTC Oxygen tank explosion,03,07,53 UTC,173,790.5 nmi from Earth CSM power down, Crew was on board the USS Iwo Jima 45 minutes later. The mission was launched at the time,02,13,00 PM EST on April 11. An anomaly occurred when the second-stage, center engine shut down two minutes early. The engine shutdown was determined to be caused by severe pogo oscillations measured at a strength of 68 g, the vehicles guidance system shut the engine down in response to sensed thrust chamber pressure fluctuations
8.
Mare Crisium
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Mare Crisium is a lunar mare located in the Moons Crisium basin, just northeast of Mare Tranquillitatis. The basin is of the Pre-Imbrian period,4.55 to 3.85 billion years ago, Mare Crisium is 555 km in diameter, and 176,000 square kilometres in area. It has a flat floor, with a ring of wrinkle ridges toward its outer boundaries. These are Dorsa Tetyaev, Dorsum Oppel, Dorsum Termier, the cape-like feature protruding into the southeast of the mare is Promontorium Agarum. On the western rim of the mare is the palimpsest Yerkes, the crater Picard is located just to the east of Yerkes, and northwest of Picard are the craters Peirce and Swift. The ray system of the crater Proclus overlie the northwestern mare, Mare Anguis can be seen northeast of Mare Crisium. A mass concentration, or gravitational high, was identified in the center of Mare Crisium from Doppler tracking of the five Lunar Orbiter spacecraft in 1968, the mascon 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 Crisium was named by Giovanni Riccioli, by the 17th century, Mare Crisium had acquired the name Caspian Sea, being labelled as such by Thomas Harriot, Pierre Gassendi and Michael Van Langren. The English astronomer William Gilberts map of c.1600 calls it Brittania after Britain, Mare Crisium is just visible from Earth with the naked eye as a small dark spot on the edge of the Moons face. It is the site of the crash-landing of Soviet Luna 15 probe in 1969, a soil sample from Mare Crisium was successfully brought to Earth on 22 August 1976 by the Soviet lunar mission Luna 24. In Robert A. Heinleins novel The Moon is a Harsh Mistress, the Sentinel, the short story from which Arthur C. Clarke developed the film 2001, A Space Odyssey with Stanley Kubrick, takes place on the Mare Crisium. In the game Mass Effect, the assignment UNC, Rogue VI, Mare Crisium at The Moon Wiki
9.
Mare Imbrium
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Mare Imbrium is a vast lava plain within 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 basins age has been estimated using U-Pb dating methods to 3938 ±4 million years ago, the Moons maria 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 was originally because later events have altered its surface, Mare Imbrium may have been formed when a proto-planet in the asteroid belt collided with the moon,3.8 billion years ago. With a diameter of 1146 km, Mare Imbrium is second only to Oceanus Procellarum in size among the maria, the Imbrium Basin is surrounded by three concentric rings of mountains, uplifted by the colossal impact event that excavated it. The ring mountains are not as developed to the north and west. The middle ring of mountains forms the Montes Alpes and the regions near the craters Archimedes. The outer ring of mountains rise roughly 7 km above the surface of Mare Imbrium, surrounding the Imbrium Basin is a region blanketed by ejecta from the impact, extending roughly 800 km outward. Mare Imbrium is about 750 miles long, a mass concentration, or gravitational high, 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, the mascon 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, 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 a map of the Moon that names Mare Imbrium Regio Magna Orientalis, michael van Langrens 1645 map named it Mare Austriacum. Mare Imbrium is visible to the eye from Earth. In the traditional Man in the Moon image seen on the Moon in Western folklore, Mare Imbrium forms the right eye. Lunokhod 1, a rover, was successfully deployed and undertook a mission lasting several months. In 1971, the crewed Apollo 15 mission landed in the region of Mare Imbrium. 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 photographs of Mare Imbrium as well as other types of scientific data
10.
Mare Ingenii
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Mare Ingenii is one of the few lunar mare features on the far side of the Moon. The mare sits in the Ingenii basin and this basin material is of the Pre-Nectarian epoch. The mare material located in Ingenii and the craters is of the Upper Imbrian epoch. The dark circular feature which dominates this mare is the crater Thomson, Mare Ingenii is incompletely and thinly covered over much of its expanse with mare lava sheets. The best flooding occurs in the crater Thomson in the ENE part of the Mare Ingenii basin, the light grey crater to the south of Ingenii is Obruchev. The mare has swirling patterns of material, similar to Reiner Gamma and to patterns within Mare Marginis. The swirls are associated with magnetic fields, prior to formal naming in 1961 by the IAU, the crater was known as Basin XIV. Mare Ingenii is located at the antipode of the Mare Imbrium impact basin, the mare contains the second instance of a lunar pit on the moon and one of several outside the Earth to date. Mare Desiderii The Swirls of Mare Ingenii, Depths of Mare Ingenii
11.
Mare Nectaris
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Mare Nectaris is a small lunar mare or sea located south of Mare Tranquillitatis southwest of Mare Fecunditatis, on the near side of the moon. Montes Pyrenaeus borders the mare to the east and Sinus Asperitatis fuses to its northwestern edge and it is 84,000 square kilometers in size. Several large craters are situated at the borders of Mare Nectaris, biggest one is lava-filled Fracastorius, which fuses with southern coast of the Sea. A prominent trio of 100-km craters Theophilus, Cyrillus and Catharina is located near northwestern coast, other notable feature is a ghost crater Daguerre, almost entirely covered with lava, in the northern part of Mare Nectaris. Mare Nectaris is located in the part of 860-km-diameter impact basin. This event marks the beginning of Nectarian period of the geologic timescale. Best-preserved part of the rim of this basin is called Rupes Altai, lava filling of Mare Nectaris is younger than the basin itself. The mare material is approximately 1000m in depth, and mainly of the Nectarian period, the crater Theophilus on the northeastern side of the mare is of the Eratosthenian period. Thus, the crater is younger than the mare to its southeast, enough subsidence has occurred to open a few arcuate grabens on the western margin of the mare. A mass concentration, or gravitational high, was identified in the center of Mare Nectaris from Doppler tracking of the five Lunar Orbiter spacecraft in 1968, the mascon was confirmed and mapped at higher resolution with later orbiters such as Lunar Prospector and GRAIL
12.
Mare Orientale
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Mare Orientale is a lunar mare. It is located on the border of the Moons nearside and is difficult to see from an Earthbound perspective. Images from spacecraft have revealed it to be one of the most striking large scale lunar features, during the 1960s, rectified images of Mare Orientale by Gerard Kuiper at the Lunar and Planetary Laboratory gave rise to the notion of it being an impact crater. Compared with most other basins, Mare Orientale is less flooded by mare basalts. The basalt in the portion of the Orientale basin is probably less than 1 km in thickness which is much less than mare basins on the earth-facing side of the moon. 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. Outward from here, ejecta extend some 500 km from the foot of the mountains and form a surface with hummocks. The Apollo program did not sample rocks from Mare Orientale so its precise age is not known, however, it is the Moons most recent impact basin, probably rather younger than the Imbrium Basin, which is about 3.85 billion years old. The surrounding basin material is of the Lower Imbrian epoch with the material being of the Upper Imbrian epoch. Located at the antipode of Mare Orientale is Mare Marginis, a mass concentration, or gravitational high, was identified in the center of Mare Orientale from Doppler tracking of the five Lunar Orbiter spacecraft in 1968. The mascon was confirmed and mapped at higher resolution with later orbiters such as Lunar Prospector, Mare Orientale is difficult to observe from Earth, as it lies at the extreme western edge of the near side. All that can be seen are the rough mountain ranges—the Montes Rook, however, the Moons libration means that on rare occasions Mare Orientale is turned slightly more toward the Earth, and becomes a little more discernible. Although various astronomers had observed hints of the mare, it was first fully described by the German astronomer Julius Franz in his 1906 book Der Mond, Franz also gave the mare its name. At the time, it was located on what by convention was considered the side of the Moon. It is on the side of the Moon as viewed from Earth. In 1961, however, the International Astronomical Union adopted the convention for East and West on the Moon. However, Moore credits Franz as discoverer in his 2009 Yearbook of Astronomy
