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Lunar Orbiter 4
Lunar Orbiter 4 was a robotic U.S. spacecraft, part of the Lunar Orbiter program, Lunar Orbiter Program, designed to orbit the Moon, after the three previous orbiters had completed the required needs for Project Apollo, Apollo mapping and site selection. It was given a more general objective, to "perform a broad systematic photographic survey of lunar surface features in order to increase the scientific knowledge of their nature, origin, and processes, and to serve as a basis for selecting sites for more detailed scientific study by subsequent orbital and landing missions". It was also equipped to collect selenodetic, radiation intensity, and micrometeoroid impact data. Mission summary The spacecraft was placed in a Free-return trajectory, cislunar trajectory and injected into an elliptical near polar high lunar orbit for data acquisition. The orbit was with an inclination of 85.5 degrees and a period of 12 hours. After initial photography on May 11, 1967 problems started ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LOIRP
The Lunar Orbiter Image Recovery Project (LOIRP) was a project to digitize the original analog data tapes from the five Lunar Orbiter spacecraft that were sent to the Moon in 1966 and 1967; it was funded by NASA, SkyCorp, SpaceRef Interactive, and private individuals. The first image to be successfully recovered by the project was released in November 2008. It was the first images of Earth from space, first photograph of the Earth from the Moon, taken in August 1966. On February 20, 2014, the project announced it had completed the primary tape capture portion of the project. One medium resolution image, most of one high resolution image and parts of three others are missing, apparently due to lapses at the time they were being recorded. The rest of the Lunar Orbiter images have been successfully recovered and have been published in NASA's Planetary Data System. Background The images taken by the Lunar Orbiter spacecraft were primarily used to locate landing sites for the crewed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Free-return Trajectory
In orbital mechanics, a free-return trajectory is a trajectory of a spacecraft traveling away from a primary body (for example, the Earth) where gravity due to a secondary body (for example, the Moon) causes the spacecraft to return to the primary body without Spacecraft propulsion, propulsion (hence the term ''free''). Many free-return trajectories are designed to intersect the atmosphere; however, periodic versions exist which pass the moon and Earth at constant periapsis, which have been proposed for cyclers. Earth–Moon The first spacecraft to use a free-return trajectory was the Soviet Luna 3 mission in October 1959. It used the Moon's gravity to send it back towards the Earth so that the photographs it had taken of the far side of the Moon could be downloaded by radio. Symmetrical free-return trajectories were studied by Arthur Schwaniger of NASA in 1963 with reference to the Earth–Moon system. He studied cases in which the trajectory at some point crosses at a right ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schroter's Valley
Schroter's Valley, frequently known by the Latinized name Vallis Schröteri, is a sinuous valley or rille on the surface of the near side of the Moon. It is located on a rise of continental ground, sometimes called the Aristarchus plateau, that is surrounded by the Oceanus Procellarum to the south and west and the Mare Imbrium to the northwest. At the southern edge of this rise are the craters Aristarchus and Herodotus. This is the largest sinuous rille on the Moon. It begins at a 6 km diameter crater located 25 km to the north of Herodotus. (The start of the rille 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 northwest, before finally bending back to the south until it reaches a 1 km high precipice at the edge of the Oceanus Procellarum. The rille has a maximum width of about 10 km, then gradually narrows to less tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aristarchus (crater)
Aristarchus is a Lunar craters, 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 displays unusually bright features when viewed through a large telescope. It is also readily identified when most of the lunar surface is illuminated by planetshine, earthshine. The crater is deeper than the Grand Canyon. The crater is named after the Greek astronomer Aristarchus of Samos. It 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. Selenography Aristarchus is located on the Aristarchus platea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mare Orientale
Mare Orientale (Latin ''orientāle'', the "eastern sea") is a lunar mare. It is located on the western border of the near side and far side of the Moon, 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, resembling a target ring bullseye. Geology 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. The structure, with the flat plain of the mare in the center, is about across and was formed by the impact of an asteroid-sized object, possibly in diameter and travelling at . Compared with most other lunar basins, Mare Orientale is less flooded by mare basalts, so that much of the basin structure is visible. The basalt in the central portion of the Orientale basin is probably less than in thickness which is much less than mare basins on the Earth-facing side of the M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stadius (crater)
Stadius is a Palimpsest, ghostly remnant of an ancient Lunar craters, lunar impact crater that has been nearly obliterated by basaltic lava flows. It was named after Flemish astronomer Johannes Stadius. It lies to the southwest of the much younger crater Eratosthenes (crater), Eratosthenes, at the north edge of Mare Insularum where the Lunar mare, mare joins Sinus Aestuum. To the west is the prominent ray crater Copernicus (lunar crater), Copernicus, 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 remains nearly intact, and it joins with a north-running ridge line that reaches the western wikt:rampart, rampart of Eratosthenes. 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 i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wichmann (crater)
Wichmann is a bowl-shaped lunar impact crater. It was named after German astronomer Moritz Ludwig George Wichmann, Moritz L. G. Wichmann. It is located in the southern half of Oceanus Procellarum on a low plateau formed from a wrinkle ridge, Dorsa Ewing. There is a small mountain chain to the north that curves away to the west that is designated Wichmann R; this is most likely the rim of a worn crater that was buried by the lava flow forming the mare. Additional low mountains lie to the south of the plateau on which Wichmann is situated. Satellite craters By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Wichmann. Gallery File:Wichmann crater AS16-M-2991.jpg, Apollo 16 image File:Wichmann R crater 3171 med.jpg, Oblique view of Wichmann R, facing southwest. Wichmann itself is just out of the view to the left. From Lunar Orbiter 3. File:Wichmann area AS16-M-2528.jpg, Similar view from Apollo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Timocharis (crater)
Timocharis is a prominent Lunar craters, lunar impact crater located on the Mare Imbrium. It was named after ancient Greek astronomer Timocharis. The closest crater of comparable dimensions is Lambert (lunar crater), Lambert to the west. The smaller craters Feuillée (crater), Feuillée and Beer (lunar crater), Beer lie to the east of Timocharis. The rim of Timocharis has a somewhat polygonal outline, with an outer wikt:rampart, 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 may have a minor ray system that extends for over . The crater is likely to have been formed in the Eratosthenian, between 3.2 and 1.1 Billion years ago, as it lacks a prominent ray system, but has not been significantly eroded by impacts. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keldysh (crater)
Keldysh is a lunar impact crater that is located in the northeastern part of the Moon, at the eastern rim of the Mare Frigoris. It lies due north of the prominent crater Atlas, and to the northeast of the notable Hercules. The crater rim is generally circular, although it gives the appearance of a slight eastward bulge. The rim edge is sharp and displays little appearance of wear, with only a tiny craterlet along the eastern edge. The inner wall slopes down without terraces to the ejecta along the base. The interior floor is relatively featureless and is free of notable impacts or ridges. This crater was previously designated Hercules A, a satellite crater of Hercules, before being renamed by the IAU The International Astronomical Union (IAU; , UAI) is an international non-governmental organization (INGO) with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach, education, and developmen ... in 1982. References * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lunar And Planetary Institute
The Lunar and Planetary Institute (LPI) is a scientific research institute dedicated to study of the Solar System, its formation, evolution, and current state. The Institute is part of the Universities Space Research Association (USRA) and is supported by the Science Mission Directorate of the National Aeronautics and Space Administration (NASA). Located at 3600 Bay Area Boulevard in Houston, Texas, the Institute serves as a scientific forum attracting visiting scientists, postdoctoral fellows, students, and resident experts; supports and serves the research community through newsletters, meetings, and other activities; collects and disseminates planetary data while facilitating the community's access to NASA astromaterials samples and facilities; engages and excites the public about space science; and invests in the development of future generations of scientists. The LPI sponsors and organizes several workshops and conferences throughout the year, including the Lunar and Pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Condensation
Condensation is the change of the state of matter from the gas phase into the liquid phase, and is the reverse of vaporization. The word most often refers to the water cycle. It can also be defined as the change in the state of water vapor to liquid water when in contact with a liquid or solid surface or cloud condensation nuclei within the atmosphere. When the transition happens from the gaseous phase into the solid phase directly, the change is called deposition. Condensation is usually associated with water. Initiation Condensation is initiated by the formation of atomic/molecular clusters of that species within its gaseous volume—like rain drop or snow flake formation within clouds—or at the contact between such gaseous phase and a liquid or solid surface. In clouds, this can be catalyzed by water-nucleating proteins, produced by atmospheric microbes, which are capable of binding gaseous or liquid water molecules. Reversibility scenarios A few distinct rev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fogging (photography)
Fogging in photography is the deterioration in the quality of the image or the negative caused either by extraneous light, other electromagnetic radiation, radioactivity or the effects of a processing chemical. It is seen either as deposition of silver or dyes across all or part of the image unrelated to the original exposure. It can be confused with chemical staining that can be produced from poorly compounded developer, contamination of processing baths or poor washing after processing. Light Light fogging is where unintended light reaches the photographic material prior to processing is seen as dark areas in the negative which tend to occur over the full width of the film including the margins. This can occur to the film in the camera because of a defect in the manufacture or use of the camera and is seen as dark areas in the negative which tend to occur over the full width of the film including the margins. In 35mm film shadowing from the sprocket holes may be seen on the f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
