|
Volcanism Of Scotland
Volcanism, vulcanism, volcanicity, or volcanic activity is the phenomenon where solids, liquids, gases, and their mixtures erupt to the surface of a solid-surface astronomical body such as a planet or a moon. It is caused by the presence of a heat source, usually internally generated, inside the body; the heat is generated by various processes, such as radioactive decay or tidal heating. This heat partially melts solid material in the body or turns material into gas. The mobilized material rises through the body's interior and may break through the solid surface. Causes For volcanism to occur, the temperature of the mantle must have risen to about half its melting point. At this point, the mantle's viscosity will have dropped to about 1021 Pascal-seconds. When large scale melting occurs, the viscosity rapidly falls to 103 Pascal-seconds or even less, increasing the heat transport rate a million-fold. The occurrence of volcanism is partially due to the fact that melted materi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astronomical Body
An astronomical object, celestial object, stellar object or heavenly body is a naturally occurring physical object, physical entity, association, or structure that exists within the observable universe. In astronomy, the terms ''object'' and ''body'' are often used interchangeably. However, an astronomical body or celestial body is a single, tightly bound, contiguous entity, while an astronomical or celestial ''object'' is a complex, less cohesively bound structure, which may consist of multiple bodies or even other objects with substructures. Examples of astronomical objects include planetary systems, star clusters, nebulae, and galaxy, galaxies, while asteroids, natural satellite, moons, planets, and stars are astronomical bodies. A comet may be identified as both a body and an object: It is a ''body'' when referring to the frozen Comet nucleus, nucleus of ice and dust, and an ''object'' when describing the entire comet with its diffuse Coma (cometary), coma and Comet tail, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astronomical Object
An astronomical object, celestial object, stellar object or heavenly body is a naturally occurring physical entity, association, or structure that exists within the observable universe. In astronomy, the terms ''object'' and ''body'' are often used interchangeably. However, an astronomical body or celestial body is a single, tightly bound, contiguous entity, while an astronomical or celestial ''object'' is a complex, less cohesively bound structure, which may consist of multiple bodies or even other objects with substructures. Examples of astronomical objects include planetary systems, star clusters, nebulae, and galaxies, while asteroids, moons, planets, and stars are astronomical bodies. A comet may be identified as both a body and an object: It is a ''body'' when referring to the frozen nucleus of ice and dust, and an ''object'' when describing the entire comet with its diffuse coma and tail. History Astronomical objects such as stars, planets, nebulae, aster ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Geographic Society
The National Geographic Society, headquartered in Washington, D.C., United States, is one of the largest nonprofit scientific and educational organizations in the world. Founded in 1888, its interests include geography, archaeology, natural science, the promotion of environmental protection, environmental and historical preservation, historical conservation movement, conservation, and the study of civilization, world culture and World history (field), history. The National Geographic Society's logo is a yellow page orientation, portrait frame—rectangular in shape—which appears on the Margin (typography), margins surrounding the front covers of its magazines and as its television channel logo. Through National Geographic Partners (a joint venture with The Walt Disney Company), the Society operates the National Geographic, magazine, National Geographic Global Networks, TV channels, a website, worldwide events, and other media operations. Overview The National Geographic S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flux Melting
In igneous petrology and volcanology, flux melting occurs when water and other volatile components are introduced to hot solid rock, depressing the solidus. In engineering and metallurgy, flux is a substance, such as salt, that produces a low melting point ( liquidus) mixture with a metal oxide. In the same way, the addition of water and other volatile compounds to rocks composed of silicate minerals lowers the melting temperature ( solidus) of those rocks. In subduction zones, the ultramafic rock of the upper mantle is melted by the addition of volatiles from the subducting plate. The subducting oceanic crust carries water and other volatiles into the mantle, primarily in the form of hydrous minerals which form as a result of the interaction of oceanic crust and seawater. Bound in the subducting crust, these volatiles are released by metamorphic dewatering into the overlying mantle wedge. The partial melting triggered by the incorporation of volatiles produces mafic magma w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pascal (unit)
The pascal (symbol: Pa) is the unit of pressure in the International System of Units (SI). It is also used to quantify internal pressure, stress, Young's modulus, and ultimate tensile strength. The unit, named after Blaise Pascal, is an SI coherent derived unit defined as one newton per square metre (N/m2). It is also equivalent to 10 barye (10 Ba) in the CGS system. Common multiple units of the pascal are the hectopascal (1 hPa = 100 Pa), which is equal to one millibar, and the kilopascal (1 kPa = 1000 Pa), which is equal to one centibar. The unit of measurement called '' standard atmosphere (atm)'' is defined as . Meteorological observations typically report atmospheric pressure in hectopascals per the recommendation of the World Meteorological Organization, thus a standard atmosphere (atm) or typical sea-level air pressure is about 1013 hPa. Reports in the United States typically use inches of mercury or millibars (hectopascals). In Cana ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Decompression Melting
Igneous rock ( ), or magmatic rock, is one of the three main rock types, the others being sedimentary and metamorphic. Igneous rocks are formed through the cooling and solidification of magma or lava. The magma can be derived from partial melts of existing rocks in either a planet's mantle or crust. Typically, the melting is caused by one or more of three processes: an increase in temperature, a decrease in pressure, or a change in composition. Solidification into rock occurs either below the surface as intrusive rocks or on the surface as extrusive rocks. Igneous rock may form with crystallization to form granular, crystalline rocks, or without crystallization to form natural glasses. Igneous rocks occur in a wide range of geological settings: shields, platforms, orogens, basins, large igneous provinces, extended crust and oceanic crust. Geological significance Igneous and metamorphic rocks make up 90–95% of the top of the Earth's crust by volume. Igneous rocks ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Max Planck Institute For Solar System Research
The Max Planck Institute for Solar System Research (abbreviation: MPS; ) is a research institute in astronomy and astrophysics located in Göttingen, Germany, where it relocated in February 2014 from the nearby village of Lindau (Katlenburg-Lindau), Lindau. The exploration of the Solar System is the central theme for research done at this institute. MPS is a part of the Max Planck Society, which operates 80 research facilities in Germany. Research MPS is organised in three departments: Sun and Heliosphere, Planets and Comets, and Solar and Stellar Interiors. In addition, since 2002 there is also an Max Planck Society#International Max Planck Research Schools, International Max Planck Research School. Subjects of research at the institute are the various objects within the Solar System. A major area of study concerns the Sun, its atmosphere, the interplanetary medium as influenced by the solar wind, as well as the impact of solar particles and radiation on the planets. The sec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arizona State University
Arizona State University (Arizona State or ASU) is a public university, public research university in Tempe, Arizona, United States. Founded in 1885 as Territorial Normal School by the 13th Arizona Territorial Legislature, the university is one of the List of United States university campuses by enrollment, largest public universities by enrollment in the United States. It was one of about 180 "normal schools" founded in the late 19th century to train teachers for the rapidly growing public common schools. Some closed, but most steadily expanded their role and became state colleges in the early 20th century, then state universities in the late 20th century. One of three universities governed by the Arizona Board of Regents, Arizona State University is a member of the Association of American Universities (AAU) and is Carnegie Classification of Institutions of Higher Education, classified among "R1: Doctoral Universities – Very High Research Activity". ASU has over 183,000 st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triton (moon)
Triton is the largest natural satellite of the planet Neptune. It is the only moon of Neptune massive enough to be list of gravitationally rounded objects of the Solar System, rounded under its own gravity and hosts a atmosphere of Triton, thin, hazy atmosphere. Triton orbits Neptune in a retrograde orbit—revolving in the opposite direction to the parent planet's rotation—the only large moon in the Solar System to do so. Triton is thought to have once been a dwarf planet from the Kuiper belt, gravitational capture, captured into Neptune's orbit by the latter's gravity. At in diameter, Triton is the list of natural satellites#List, seventh-largest moon in the Solar System, the second-largest planetary moon in relation to its primary (after Earth's Moon), and larger than all of the known dwarf planets. The mean density is , reflecting a composition of approximately 30–45% ice, water ice by mass, with the rest being mostly rock and metal. Triton is differentiated, with a c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silicate
A silicate is any member of a family of polyatomic anions consisting of silicon and oxygen, usually with the general formula , where . The family includes orthosilicate (), metasilicate (), and pyrosilicate (, ). The name is also used for any salt of such anions, such as sodium metasilicate; or any ester containing the corresponding chemical group, such as tetramethyl orthosilicate. The name "silicate" is sometimes extended to any anions containing silicon, even if they do not fit the general formula or contain other atoms besides oxygen; such as hexafluorosilicate . Most commonly, silicates are encountered as silicate minerals. For diverse manufacturing, technological, and artistic needs, silicates are versatile materials, both natural (such as granite, gravel, and garnet) and artificial (such as Portland cement, ceramics, glass, and waterglass). Structural principles In most silicates, a silicon atom occupies the center of an idealized tetrahedron whose cor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terrestrial Planet
A terrestrial planet, tellurian planet, telluric planet, or rocky planet, is a planet that is composed primarily of silicate, rocks or metals. Within the Solar System, the terrestrial planets accepted by the IAU are the inner planets closest to the Sun: Mercury, Venus, Earth and Mars. Among astronomers who use the geophysical definition of a planet, two or three planetary-mass satellites – Earth's Moon, Io, and sometimes Europa – may also be considered terrestrial planets. The large rocky asteroids Pallas and Vesta are sometimes included as well, albeit rarely. The terms "terrestrial planet" and "telluric planet" are derived from Latin words for Earth (''Terra'' and ''Tellus''), as these planets are, in terms of structure, ''Earth-like''. Terrestrial planets are generally studied by geologists, astronomers, and geophysicists. Terrestrial planets have a solid planetary surface, making them substantially different from larger gaseous planets, which are composed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radionuclide
A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) is a nuclide that has excess numbers of either neutrons or protons, giving it excess nuclear energy, and making it unstable. This excess energy can be used in one of three ways: emitted from the nucleus as gamma radiation; transferred to one of its electrons to release it as a conversion electron; or used to create and emit a new particle (alpha particle or beta particle) from the nucleus. During those processes, the radionuclide is said to undergo radioactive decay. These emissions are considered ionizing radiation because they are energetic enough to liberate an electron from another atom. The radioactive decay can produce a stable nuclide or will sometimes produce a new unstable radionuclide which may undergo further decay. Radioactive decay is a random process at the level of single atoms: it is impossible to predict when one particular atom will decay. However, for a collection of atoms of a single nu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
