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Great Meteor Storm Of 1833
The Leonids ( ) are a prolific meteor shower associated with the comet Tempel–Tuttle, which are also known for their spectacular meteor storms that occur about every 33 years. The Leonids get their name from the location of their radiant in the constellation Leo: the meteors appear to radiate from that point in the sky. Their proper Greek name should be Leonids ( grc, Λεοντίδαι, Leontídai, label=none), but the word was initially constructed as a Greek/Latin hybrid and it has been used since. The meteor shower peak should be on November 17, 2022, but any outburst is likely to be from the 1733 meteoroid stream. Earth moves through the meteoroid stream of particles left from the passages of a comet. The stream comprises solid particles, known as meteoroids, ejected by the comet as its frozen gases evaporate under the heat of the Sun when it is close enough – typically closer than Jupiter's orbit. The Leonids are a fast moving stream which encounter the path of Ear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leonid Meteor
Leonid (russian: Леонид ; uk, Леонід ; be, Леанід, Ljeaníd ) is a Slavic version of the given name Leonidas. The French version is Leonide. People with the name include: *Leonid Andreyev (1871–1919), Russian playwright and short-story writer who led the Expressionist movement in the national literature *Leonid Brezhnev (1906–1982), leader of the USSR from 1964 to 1982 *Leonid Buryak (b. 1953), USSR/Ukraine-born Olympic-medal-winning soccer player and coach *Leonid Bykov (1928–1979), Soviet and Ukrainian actor, film director, and script writer *Leonid Desyatnikov (b. 1955), Soviet and Russian opera and film composer *Leonid Feodorov (1879–1935), a bishop and Exarch for the Russian Catholic Church, and survivor of the Gulag *Leonid Filatov (1946–2003), Soviet and Russian actor, director, poet, and pamphleteer *Leonid Gaidai, (1923–1993), Soviet comedy film director * Leonid Geishtor (b. 1936), USSR (Belarus)-born Olympic champion Canadian pairs s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poynting–Robertson Effect
The Poynting–Robertson effect, also known as Poynting–Robertson drag, named after John Henry Poynting and Howard P. Robertson, is a process by which solar radiation causes a dust grain orbiting a star to lose angular momentum relative to its orbit around the star. This is related to radiation pressure tangential to the grain's motion. This causes dust that is small enough to be affected by this drag, but too large to be blown away from the star by radiation pressure, to spiral slowly into the star. In the case of the Solar System, this can be thought of as affecting dust grains from to in diameter. Larger dust is likely to collide with another object long before such drag can have an effect. Poynting initially gave a description of the effect in 1903 based on the luminiferous aether theory, which was superseded by the theories of relativity in 1905–1915. In 1937 Robertson described the effect in terms of general relativity. History Robertson considered dust motion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cheyenne
The Cheyenne ( ) are an Indigenous people of the Great Plains. Their Cheyenne language belongs to the Algonquian language family. Today, the Cheyenne people are split into two federally recognized nations: the Southern Cheyenne, who are enrolled in the Cheyenne and Arapaho Tribes in Oklahoma, and the Northern Cheyenne, who are enrolled in the Northern Cheyenne Tribe of the Northern Cheyenne Indian Reservation in Montana. The Cheyenne comprise two Native American tribes, the Só'taeo'o or Só'taétaneo'o (more commonly spelled as Suhtai or Sutaio) and the Tsétsêhéstâhese (also spelled Tsitsistas, The term for the Cheyenne homeland is ''Tsiihistano''. Language The Cheyenne of Montana and Oklahoma speak the Cheyenne language, known as ''Tsêhésenêstsestôtse'' (common spelling: Tsisinstsistots). Approximately 800 people speak Cheyenne in Oklahoma. There are only a handful of vocabulary differences between the two locations. The Cheyenne alphabet contains 14 letters. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Native Americans In The United States
Native Americans, also known as American Indians, First Americans, Indigenous Americans, and other terms, are the Indigenous peoples of the mainland United States ( Indigenous peoples of Hawaii, Alaska and territories of the United States are generally known by other terms). There are 574 federally recognized tribes living within the US, about half of which are associated with Indian reservations. As defined by the United States Census, "Native Americans" are Indigenous tribes that are originally from the contiguous United States, along with Alaska Natives. Indigenous peoples of the United States who are not listed as American Indian or Alaska Native include Native Hawaiians, Samoan Americans, and the Chamorro people. The US Census groups these peoples as " Native Hawaiian and other Pacific Islanders". European colonization of the Americas, which began in 1492, resulted in a precipitous decline in Native American population because of new diseases, wars, ethni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding the National Advisory Committee for Aeronautics (NACA), to give the U.S. space development effort a distinctly civilian orientation, emphasizing peaceful applications in space science. NASA has since led most American space exploration, including Project Mercury, Project Gemini, the 1968-1972 Apollo Moon landing missions, the Skylab space station, and the Space Shuttle. NASA supports the International Space Station and oversees the development of the Orion spacecraft and the Space Launch System for the crewed lunar Artemis program, Commercial Crew spacecraft, and the planned Lunar Gateway space station. The agency is also responsible for the Launch Services Program, which provides oversight of launch operations and countdown management f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Halley's Comet
Halley's Comet or Comet Halley, officially designated 1P/Halley, is a short-period comet visible from Earth every 75–79 years. Halley is the only known short-period comet that is regularly visible to the naked eye from Earth, and thus the only naked-eye comet that can appear twice in a human lifetime. Halley last appeared in the inner parts of the Solar System in 1986 and will next appear in mid-2061. Halley's periodic returns to the inner Solar System have been observed and recorded by astronomers around the world since at least 240 BC. But it was not until 1705 that the English astronomer Edmond Halley understood that these appearances were reappearances of the same comet. As a result of this discovery, the comet is named after Halley. During its 1986 visit to the inner Solar System, Halley's Comet became the first comet to be observed in detail by spacecraft, providing the first observational data on the structure of a comet nucleus and the mechanism of coma and tail f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seventh-day Adventist
The Seventh-day Adventist Church is an Adventism, Adventist Protestantism, Protestant Christian denomination which is distinguished by its observance of Saturday, the Names of the days of the week#Numbered days of the week, seventh day of the week in the Christian Gregorian calendar, (Gregorian) and the Hebrew calendar, as the Sabbath, and its emphasis on the imminent Second Coming (advent) of Jesus Christ. The denomination grew out of the Millerism, Millerite movement in the United States during the mid-19th century and it was formally established in 1863. Among its co-founders was Ellen G. White, whose extensive writings are still held in high regard by the church. Much of the theology of the Seventh-day Adventist Church corresponds to common Evangelicalism, evangelical Christian teachings, such as the Trinity and the Biblical infallibility, infallibility of Scripture. Distinctive post-tribulation rapture, post-tribulation teachings include the Christian mortalism, unconscio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Venus
Venus is the second planet from the Sun. It is sometimes called Earth's "sister" or "twin" planet as it is almost as large and has a similar composition. As an interior planet to Earth, Venus (like Mercury) appears in Earth's sky never far from the Sun, either as morning star or evening star. Aside from the Sun and Moon, Venus is the brightest natural object in Earth's sky, capable of casting visible shadows on Earth at dark conditions and being visible to the naked eye in broad daylight. Venus is the second largest terrestrial object of the Solar System. It has a surface gravity slightly lower than on Earth and has a very weak induced magnetosphere. The atmosphere of Venus, mainly consists of carbon dioxide, and is the densest and hottest of the four terrestrial planets at the surface. With an atmospheric pressure at the planet's surface of about 92 times the sea level pressure of Earth and a mean temperature of , the carbon dioxide gas at Venus's surface is in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meteoroid
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 meteoroid th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sirius
Sirius is the list of brightest stars, brightest star in the night sky. Its name is derived from the Ancient Greek language, Greek word , or , meaning 'glowing' or 'scorching'. The star is designated α Canis Majoris, Latinisation of names, Latinized to Alpha Canis Majoris, and abbreviated Alpha CMa or α CMa. With a visual apparent magnitude of −1.46, Sirius is almost twice as bright as Canopus, the next brightest star. Sirius is a binary star consisting of a main-sequence star of spectral type A-type main-sequence star, A0 or A1, termed Sirius A, and a faint white dwarf companion of spectral type DA2, termed Sirius B. The distance between the two varies between 8.2 and 31.5 astronomical units as they orbit every 50 years. Sirius appears bright because of its intrinsic luminosity and its proximity to the Solar System. At a distance of , the Sirius system is one of Earth's List of nearest stars, nearest neighbours. Sirius is gradually moving closer to the Solar S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apparent Magnitude
Apparent magnitude () is a measure of the brightness of a star or other astronomical object observed from Earth. An object's apparent magnitude depends on its intrinsic luminosity, its distance from Earth, and any extinction of the object's light caused by interstellar dust along the line of sight to the observer. The word ''magnitude'' in astronomy, unless stated otherwise, usually refers to a celestial object's apparent magnitude. The magnitude scale dates back to the ancient Roman astronomer Claudius Ptolemy, whose star catalog listed stars from 1st magnitude (brightest) to 6th magnitude (dimmest). The modern scale was mathematically defined in a way to closely match this historical system. The scale is reverse logarithmic: the brighter an object is, the lower its magnitude number. A difference of 1.0 in magnitude corresponds to a brightness ratio of \sqrt /math>, or about 2.512. For example, a star of magnitude 2.0 is 2.512 times as bright as a star of magnitude 3.0, 6. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delta Ursae Majoris
Delta Ursae Majoris (δ Ursae Majoris, abbreviated Delta UMa, δ UMa), formally named Megrez , is a star in the northern constellation of Ursa Major. With an apparent magnitude of +3.3, it is the dimmest of the seven stars in the Big Dipper asterism. Parallax measurements yield a distance estimate of from the Sun. Stellar properties Delta Ursae Majoris has 63% more mass than the Sun and is about 1.4 times its radius. It has a stellar classification of A3 V, which means it is an A-type main sequence star that is generating energy at its core through the nuclear fusion of hydrogen. It shines at 14 times the luminosity of the Sun, with this energy being emitted from its outer envelope at an effective temperature of 9,480 K. This gives it the white hue typical of an A-type star. This star has an excess emission of infrared radiation, indicating the presence of circumstellar matter. This forms a debris disk around an orbital radius of 16 ast ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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