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Anaxagoras (crater)
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 crater Goldschmidt. 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. It is consequently mapped as part of the Copernican System.The geologic history of the Moon, 1987, Wilhelms, Don E.; with sections by McCauley, John F.; Trask, Newell J. USGS Professional Paper: 1348. Plate 11: Copernican Systemonline 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.) T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anaxagoras Crater 4128 H2
Anaxagoras (; grc-gre, Ἀναξαγόρας, ''Anaxagóras'', "lord of the assembly"; 500 – 428 BC) was a Pre-Socratic Greek philosopher. Born in Clazomenae at a time when Asia Minor was under the control of the Persian Empire, Anaxagoras came to Athens. According to Diogenes Laërtius and Plutarch, in later life he was charged with impiety and went into exile in Lampsacus; the charges may have been political, owing to his association with Pericles, if they were not fabricated by later ancient biographers. Responding to the claims of Parmenides on the impossibility of change, Anaxagoras introduced the concept of ''Nous'' (Cosmic Mind) as an ordering force. He also gave a number of novel scientific accounts of natural phenomena, including the notion of panspermia, that life exists throughout the universe and could be distributed everywhere. He deduced a correct explanation for eclipses and described the Sun as a fiery mass larger than the Peloponnese, as well as at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Birmingham (crater)
Birmingham is the surviving remnant of a lunar impact crater. It is named after the astronomer John Birmingham (not, as is often stated, the British city nor its Alabama namesake). The crater is located near the northern limb of the Moon, and so is viewed from the Earth at a low angle. All that survives of the original formation is an irregular perimeter of low, indented ridges surrounding the lava-resurfaced interior. The inner floor is marked by several tiny craterlets, and the surface is unusually rough for a walled plain. The low angle of illumination allows fine details of this boulder-strewn field to be seen more clearly. Location The Birmingham formation lies just to the north of the Mare Frigoris Mare Frigoris (Latin ''frīgōris'', the "Sea of Cold") is a lunar mare in the far north of the Moon. It is located in the outer rings of the Procellarum basin, just north of Mare Imbrium, and stretches east to north of Mare Serenitatis. It is ju ..., and to the east of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terrace
Terrace may refer to: Landforms and construction * Fluvial terrace, a natural, flat surface that borders and lies above the floodplain of a stream or river * Terrace, a street suffix * Terrace, the portion of a lot between the public sidewalk and the street * Terrace (earthworks), a leveled surface built into the landscape for agriculture or salt production * Terrace (building), a raised flat platform * Terrace garden, an element where a raised flat paved or gravelled section overlooks a prospect * Terrace (geology), a step-like landform that borders a shoreline or river floodplain * Terraced house, a style of housing where identical individual houses are cojoined into rows * Terrace, the roof of a building, especially one accessible to the residents for various purposes * Terrace, a sidewalk cafe * Terrace (stadium), standing spectator areas, especially in Europe and South America, or the sloping portion of the outfield in a baseball stadium, not necessarily for seating, but for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albedo
Albedo (; ) is the measure of the diffuse reflection of sunlight, solar radiation out of the total solar radiation and measured on a scale from 0, corresponding to a black body that absorbs all incident radiation, to 1, corresponding to a body that reflects all incident radiation. Surface albedo is defined as the ratio of Radiosity (radiometry), radiosity ''J''e to the irradiance ''E''e (flux per unit area) received by a surface. The proportion reflected is not only determined by properties of the surface itself, but also by the spectral and angular distribution of solar radiation reaching the Earth's surface. These factors vary with atmospheric composition, geographic location, and time (see position of the Sun). While bi-hemispherical reflectance is calculated for a single angle of incidence (i.e., for a given position of the Sun), albedo is the directional integration of reflectance over all solar angles in a given period. The temporal resolution may range from seconds (as ob ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Geological Survey
The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, and the natural hazards that threaten it. The organization's work spans the disciplines of biology, geography, geology, and hydrology. The USGS is a fact-finding research organization with no regulatory responsibility. The agency was founded on March 3, 1879. The USGS is a bureau of the United States Department of the Interior; it is that department's sole scientific agency. The USGS employs approximately 8,670 people and is headquartered in Reston, Virginia. The USGS also has major offices near Lakewood, Colorado, at the Denver Federal Center, and Menlo Park, California. The current motto of the USGS, in use since August 1997, is "science for a changing world". The agency's previous slogan, adopted on the occasion of its hundredt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Donald Wilhelms
Don Edward Wilhelms (born July 5, 1930) is a former United States Geological Survey geologist who contributed to geologic mapping of the Earth's moon and to the geologic training of the Apollo astronauts. He is the author of '' To a Rocky Moon: A Geologist's History of Lunar Exploration'' (1993), ''The geologic history of the Moon'' (1987), and he co-authored the ''Geologic Map of the Near Side of the Moon'' (1971) with John F. McCauley. Wilhelms also contributed to ''Apollo Over the Moon: A View from Orbit'' (NASA SP-362). He has also contributed to the study of Mars (including Mariner 9), Mercury, and Ganymede. Biography He was born July 5, 1930. Wilhelms was the recipient of the G. K. Gilbert Award in 1988. He received the Shoemaker Distinguished Lunar Scientist Award in 2010 at the Ames Research Center The Ames Research Center (ARC), also known as NASA Ames, is a major NASA research center at Moffett Federal Airfield in California's Silicon Valley. It was founded in 19 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copernican Period
The Copernican Period in the lunar geologic timescale runs from approximately 1.1 billion years ago to the present day. The base of the Copernican period is defined by impact craters that possess bright optically immature ray systems. The crater Copernicus is a prominent example of rayed crater, but it does not mark the base of the Copernican period. Copernican age deposits are mostly represented by crater ejecta, but a small area of mare basalt has covered part of (and is thus younger than) some of the rays of the Copernican crater Lichtenberg, and therefore the basalt is mapped as Copernican age. Definition The base of the Copernican period is defined based on the recognition that freshly excavated materials on the lunar surface are generally "bright" and that they become darker over time as a result of space weathering processes. Operationally, this period was originally defined as the time at which impact craters "lost" their bright ray systems. This definition, howev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plato (crater)
Plato is a lava-filled lunar impact crater on the Moon. Its diameter is 101 km. It was named after ancient Greek philosopher Plato. It is located on the northeastern shore of the Mare Imbrium, at the western extremity of the Montes Alpes mountain range. In the mare to the south are several rises collectively named the Montes Teneriffe. To the north lies the wide stretch of the Mare Frigoris. East of the crater, among the Montes Alpes, are several rilles collectively named the Rimae Plato. The age of Plato is about 3.84 billion years, only slightly 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 oval due to foreshortening. The flat floor of Plato has a relatively low ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ray System
A ray system comprises radial streaks of fine '' ejecta'' thrown out during the formation of an impact crater, looking somewhat like many thin spokes coming from the hub of a wheel. The rays may extend for lengths up to several times the diameter of their originating crater, and are often accompanied by small secondary craters formed by larger chunks of ejecta. Ray systems have been identified on the Moon, Earth ( Kamil Crater), Mercury, and some moons of the outer planets. Originally it was thought that they existed only on planets or moons lacking an atmosphere, but more recently they have been identified on Mars in infrared images taken from orbit by '' 2001 Mars Odyssey''s thermal imager. Rays appear at visible, and in some cases infrared wavelengths, when ejecta are made of material with different reflectivity (i.e., albedo) or thermal properties from the surface on which they are deposited. Typically, visible rays have a higher albedo than the surrounding surface. More rarel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epigenes (crater)
Epigenes is a lunar impact crater that is located in the north part of the Moon, and is sufficiently close to the northern limb to appear significantly foreshortened from the Earth. It lies just to the northwest of the remains of the walled plain W. Bond. Due north of Epigenes is Goldschmidt, and the ruined crater Birmingham lies just to the southwest. This formation is a picture in contrasts. The north and northwest parts of the rim are well-formed with little appearance of wear, while the remainder of the rim is notably eroded, particularly in the east-southeastern half. The western half of the interior floor is smooth and nearly featureless, while the remainder is somewhat hummocky and appears covered in ejecta Ejecta (from the Latin: "things thrown out", singular ejectum) are particles ejected from an area. In volcanology, in particular, the term refers to particles including pyroclastic materials (tephra) that came out of a volcanic explosion and magma ... from the east. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 occu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goldschmidt (crater)
Goldschmidt is a large lunar impact crater of the variety commonly termed a walled plain. It lies in the northern part of the Moon's near side, and appears oval in shape due to foreshortening. The rim is actually relatively circular, although the western rim is overlain by the prominent crater Anaxagoras. Nearly attached to the southeast rim is Barrow, and the two formations are separated by a rugged rise about 30 kilometers across. Further to the south is Epigenes. The heavily eroded outer rim of Goldschmidt is rugged and irregular, with an inner wall that is incised in several locations by small impacts. Much of the western rim no longer exists, due to the overlapping Anaxagoras and the smaller Anaxagoras A, and the ejecta from these formations covers the western third of the interior floor. The remaining floor is nearly level and flat, most likely having been resurfaced by lava Lava is molten or partially molten rock (magma) that has been expelled from the interior of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
