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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 rar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fresh Impact Crater HiRise 2013
Fresh or FRESH may refer to: People *DJ Fresh (born 1977), UK-based drum and bass artist *DJ Fresh (producer), US-based R&B producer born Marqus Brown Arts, entertainment, and media Films * ''Fresh'' (1994 film), a crime film * ''Fresh'' (2009 film), a documentary film on sustainable agriculture * ''Fresh'' (2022 film), a thriller film Music Groups and labels *Fresh (band), a London-based pop-punk band *Fresh Records (UK) *Fresh Records (US) Albums * ''Fresh'' (Shawn Desman album) * ''Fresh!'' (Gina G album) * ''Fresh'' (Raspberries album) * ''Fresh'' (Sly and the Family Stone album) * ''Fresh'' (Teddybears album) * ''Fresh'' (Melissa Tkautz album) *''Fresh'', a 2010 album by Tye Tribbett Songs * "Fresh" (Devo song) * "Fresh" (Kool & the Gang song), a 1984 song by Kool & The Gang *" F.R.E.S.H.", a 2007 song by Scribe *"Fresh", a 1996 song by Daft Punk from ''Homework'' Radio * Fresh (Coventry & Warwickshire), an English radio station, covering the West Midlands *'' Fresh 40 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albedo
Albedo (; ) is the measure of the diffuse reflection of 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 ''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 obtained from flux measurements) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copernicus (lunar Crater)
Copernicus is a lunar impact crater located in eastern Oceanus Procellarum. It was named after the astronomer Nicolaus Copernicus. It typifies craters that formed during the Copernican period in that it has a prominent ray system. It may have been created by debris from the breakup of the parent body of asteroid 495 Eulalia 800 million years ago. Characteristics Copernicus is visible using binoculars, and is located slightly northwest of the center of the Moon's Earth-facing hemisphere. South of the crater is the Mare Insularum, and to the south-south west is the crater Reinhold. North of Copernicus are the Montes Carpatus, which lie at the south edge of Mare Imbrium. West of Copernicus is a group of dispersed lunar hills. Due to its relative youth, the crater has remained in a relatively pristine shape since it formed. The circular rim has a discernible hexagonal form, with a terraced inner wall and a 30 km wide, sloping rampart that descends nearly a kilometer to th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aristarchus (crater)
Aristarchus is a 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 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 plateau, an elevated rocky rise ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron Oxide
Iron oxides are chemical compounds composed of iron and oxygen. Several iron oxides are recognized. All are black magnetic solids. Often they are non-stoichiometric. Oxyhydroxides are a related class of compounds, perhaps the best known of which is rust. Iron oxides and oxyhydroxides are widespread in nature and play an important role in many geological and biological processes. They are used as iron ores, pigments, catalysts, and in thermite, and occur in hemoglobin. Iron oxides are inexpensive and durable pigments in paints, coatings and colored concretes. Colors commonly available are in the "earthy" end of the yellow/orange/red/brown/black range. When used as a food coloring, it has E number E172. Stoichiometries Iron oxides feature as ferrous ( Fe(II)) or ferric (Fe(III)) or both. They adopt octahedral or tetrahedral coordination geometry. Only a few oxides are significant at the earth's surface, particularly wüstite, magnetite, and hematite. * Oxides of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eugene Shoemaker
Eugene Merle Shoemaker (April 28, 1928 – July 18, 1997) was an American geologist. He co-discovered Comet Shoemaker–Levy 9 with his wife Carolyn S. Shoemaker and David H. Levy. This comet hit Jupiter in July 1994: the impact was televised around the world. Shoemaker also studied terrestrial craters, such as Barringer Meteor Crater in Arizona, and along with Edward Chao provided the first conclusive evidence of its origin as an impact crater. He was also the first director of the United States Geological Survey's Astrogeology Research Program. He was killed in a car accident while visiting an impact crater site in Australia. After his death, some of his ashes were carried to the Moon with the Lunar Prospector mission. Early life and formal education Shoemaker was born in Los Angeles, California, the son of Muriel May (née Scott), a teacher; and George Estel Shoemaker, who worked in farming, business, teaching, and motion pictures. His parents were natives of Nebraska. D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kuiper Crater EW1065899876G
Kuiper is a Dutch occupational surname meaning cooper. Common spelling variants include Kuyper, Kuipers, Kuijper, Kuijpers, Kuypers, and De Kuyper. Notable people with the name include: Kuiper *Adrian Kuiper (born 1959), South African cricketer *Barend Klaas Kuiper (1877–1961), Dutch-American historian * David Kuiper (born 1980), Dutch rower *Duane Kuiper (born 1950), American baseball player * Edith Kuiper (born 1960), Dutch economist *Franciscus Bernardus Jacobus Kuiper (1907–2003), Dutch Indologist *Gerard Kuiper (1905–1973), Dutch-American astronomer after whom the Kuiper belt was named * Glen Kuiper (born 1963) American broadcaster *Hennie Kuiper (born 1949), Dutch cyclist * J. P. Kuiper (1922–1985), Dutch professor of social medicine *Michael Kuiper (born 1989), Dutch martial artist * Nick Kuiper (born 1982), Canadian ice hockey player *Nicky Kuiper (born 1989), Dutch footballer *Nicolaas Kuiper (1920–1994), Dutch mathematician, known for Kuiper's test, Kuiper's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lichtenberg (crater)
Lichtenberg is an isolated lunar impact crater located in the western part of the Oceanus Procellarum. The nearest crater of note is Briggs to the south. Lichtenberg has a small system of rays, a characteristic of Copernican age craters. The rays extend to the north and west of the crater but not elsewhere. The remaining flanks of the surface about the crater exhibit the low albedo of the lunar mare, and the mare deposits have overlaid the existing rays on the east and south sides of the crater. These are thus among the youngest deposits of basaltic lava on the Moon, and are believed to be less than 1 billion years in age. However, the most recent lunar geologic map (2020) does not show the mare next to Lichtenberg as being Copernican in age - it is mapped as Upper Imbrian. Lunar scientist Paul Spudis advocates an unmanned sample-return mission to the young mare to obtain an absolute radiometric date that would constrain the time period of the formation of the maria on th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Regolith
Regolith () is a blanket of unconsolidated, loose, heterogeneous superficial deposits covering solid rock. It includes dust, broken rocks, and other related materials and is present on Earth, the Moon, Mars, some asteroids, and other terrestrial planets and moons. Etymology The term '' regolith'' combines two Greek words: (), 'blanket', and (), 'rock'. The American geologist George P. Merrill first defined the term in 1897, writing: Earth Earth's regolith includes the following subdivisions and components: * soil or pedolith * alluvium and other transported cover, including that transported by aeolian, glacial, marine, and gravity flow processes. * "saprolith'", generally divided into the ** ''upper saprolite'': completely oxidised bedrock ** ''lower saprolite'': chemically reduced partially weathered rocks ** ''saprock'': fractured bedrock with weathering restricted to fracture margins * volcanic ash and lava flows that are interbedded with unconsolidated materi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meteor
A meteoroid () is a small rocky or metallic body in outer space. Meteoroids are defined as objects significantly smaller than asteroids, ranging in size from grains to objects up to a meter wide. Objects smaller than this are classified as micrometeoroids or space dust. Most are fragments from comets or asteroids, whereas others are collision impact debris ejected from bodies such as the Moon or Mars. When a meteoroid, comet, or asteroid enters Earth's atmosphere at a speed typically in excess of , aerodynamic heating of that object produces a streak of light, both from the glowing object and the trail of glowing particles that it leaves in its wake. This phenomenon is called a meteor or "shooting star". Meteors typically become visible when they are about 100 km above sea level. A series of many meteors appearing seconds or minutes apart and appearing to originate from the same fixed point in the sky is called a meteor shower. A meteorite is the remains of a met ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cosmic Ray
Cosmic rays are high-energy particles or clusters of particles (primarily represented by protons or atomic nuclei) that move through space at nearly the speed of light. They originate from the Sun, from outside of the Solar System in our own galaxy, and from distant galaxies. Upon impact with Earth's atmosphere, cosmic rays produce showers of secondary particles, some of which reach the surface, although the bulk is deflected off into space by the magnetosphere or the heliosphere. Cosmic rays were discovered by Victor Hess in 1912 in balloon experiments, for which he was awarded the 1936 Nobel Prize in Physics. Direct measurement of cosmic rays, especially at lower energies, has been possible since the launch of the first satellites in the late 1950s. Particle detectors similar to those used in nuclear and high-energy physics are used on satellites and space probes for research into cosmic rays. Data from the Fermi Space Telescope (2013) have been interpreted as evidence ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Weathering
Space weathering is the type of weathering that occurs to any object exposed to the harsh environment of outer space. Bodies without atmospheres (including the Moon, Mercury, the asteroids, comets, and most of the moons of other planets) take on many weathering processes: * collisions of galactic cosmic rays and solar cosmic rays, * irradiation, implantation, and sputtering from solar wind particles, and * bombardment by different sizes of meteorites and micrometeorites. Space weathering is important because these processes affect the physical and optical properties of the surface of many planetary bodies. Therefore, it is critical to understand the effects of space weathering in order to properly interpret remotely sensed data. History Much of our knowledge of the space weathering process comes from studies of the lunar samples returned by the Apollo program, particularly the lunar soils (or regolith). The constant flux of high energy particles and micrometeorites, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
