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Superbolide
A bolide is normally taken to mean an exceptionally bright meteor, but the term is subject to more than one definition, according to context. It may refer to any large crater-forming body, or to one that explodes in the atmosphere. It can be a synonym for a fireball, sometimes specific to those with an apparent magnitude of −4 or brighter. Definitions The word ''bolide'' (; from Italian via Latin, ) may refer to somewhat different phenomena depending on the context in which the word appears, and readers may need to make inferences to determine which meaning is intended in a particular publication. An early usage occurs in ''Natural History'', where Pliny the Elder describes two types of prodigies, "those which are called lampades and those which are called bolides". At least one of the prodigies described by Pliny (a "spark" that fell, grew to the "size of the moon", and "returned into the heavens") has been interpreted by astronomers as a bolide in the modern sense. His d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fireball (meteor)
A meteor, known colloquially as a shooting star, is a glowing streak of a small body (usually meteoroid) going through Earth's atmosphere, after being heated to incandescence by collisions with air molecules in the upper atmosphere, creating a streak of light via its rapid motion and sometimes also by shedding glowing material in its wake. Although a meteor may seem to be a few thousand feet from the Earth, meteors typically occur in the mesosphere at altitudes from . The root word ''meteor'' comes from the Ancient Greek, Greek ''meteōros'', meaning "high in the air". Millions of meteors occur in Earth's atmosphere daily. Most meteoroids that cause meteors are about the size of a grain of sand, i.e. they are usually millimeter-sized or smaller. Meteoroid sizes can be calculated from their mass and density which, in turn, can be estimated from the observed meteor trajectory in the upper atmosphere. Meteors may occur in meteor shower, showers, which arise when Earth passes throu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chelyabinsk Meteor
The Chelyabinsk meteor () was a superbolide that entered Earth's atmosphere over the southern Ural region in Russia on 15 February 2013 at about 09:20 YEKT (03:20 UTC). It was caused by an approximately , near-Earth asteroid that entered the atmosphere at a shallow 18‐degree angle with a speed relative to Earth of . The light from the meteor was briefly brighter than the Sun, visible as far as away. It was observed in a wide area of the region and in neighbouring republics. Some eyewitnesses also reported feeling intense heat from the fireball. The object exploded in a meteor air burst over Chelyabinsk Oblast, at a height of about . The explosion generated a bright flash, producing a hot cloud of dust and gas that penetrated to , and many surviving small fragmentary meteorites. Most of the object's energy was absorbed by the atmosphere, creating a large shock wave. The asteroid had a total kinetic energy before atmospheric impact equivalent to the blast yield of , est ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2009 Sulawesi Superbolide
The 2009 Sulawesi superbolide was an atmospheric Meteoroid#Fireball, fireball blast over Indonesia on October 8, 2009, at approximately 03:00 UTC (11:00 local time), near the coastal city of Watampone in South Sulawesi, island of Sulawesi. The meteorite, meteoritic impactor broke up at an estimated height of 15–20 km. The impact energy of the bolide was estimated in the 10 to 50 kiloton TNT equivalent range, with the higher end of this range being more likely. The likely size of the impactor was 5–10 m diameter. References External links * Explosions in 2009 Modern Earth impact events, 2009 Sulawesi superbolid 2009 in Indonesia 2009 in outer space 21st century in Sulawesi October 2009 in Indonesia 21st-century astronomical events Explosions in Indonesia {{meteoroid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Impact Event
An impact event is a collision between astronomical objects causing measurable effects. Impact events have been found to regularly occur in planetary systems, though the most frequent involve asteroids, comets or meteoroids and have minimal effect. When large objects impact terrestrial planets such as the Earth, there can be significant physical and Biosphere, biospheric consequences, as the impacting body is usually traveling at several kilometres per second (km/s), with a minimum impact speed of 11.2 km/s (7.0 mi/s) for bodies striking Earth. Atmosphere, While planetary atmospheres can mitigate some of these impacts through the effects of atmospheric entry, many large bodies retain sufficient energy to reach the surface and cause substantial damage. This results in the formation of Impact crater, impact craters and Impact structure, structures, shaping the dominant landforms found across various types of solid objects found in the Solar System. Their prevalence and ubiquity pres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ernst Chladni
Ernst Florens Friedrich Chladni (, , ; 30 November 1756 – 3 April 1827) was a German physicist and musician. His most important work, for which he is sometimes labeled the father of acoustics, included research on vibrating plates and the calculation of the speed of sound for different gases. He also undertook pioneering work in the study of meteorites and is regarded by some as the father of meteoritics. Early life Although Chladni was born in Wittenberg in Saxony, his family originated from Kremnica, then part of the Kingdom of Hungary and today a mining town in central Slovakia. Chladni has therefore been identified as German, Hungarian and Slovak. Chladni came from an educated family of academics and learned men. Chladni's great-grandfather, the Lutheran clergyman Georg Chladni (1637–1692), had left Kremnica in 1673 during the Counter Reformation. Chladni's grandfather, Martin Chladni (1669–1725), was also a Lutheran theologian and, in 1710, became profess ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geologist
A geologist is a scientist who studies the structure, composition, and History of Earth, history of Earth. Geologists incorporate techniques from physics, chemistry, biology, mathematics, and geography to perform research in the Field research, field and the laboratory. Geologists work in the Energy industry, energy and mining sectors to exploit Natural resource, natural resources. They monitor environmental hazards such as earthquakes, volcanoes, tsunamis and landslides. Geologists are also important contributors to climate change discussions. History James Hutton is often viewed as the first modern geologist. In 1785 he presented a paper entitled ''Theory of the Earth'' to the Royal Society of Edinburgh. In his paper, he explained his theory that the Earth must be much older than had previously been supposed to allow enough time for mountains to be eroded and for sediments to form new rocks at the bottom of the sea, which in turn were raised up to become dry land. Hutton pub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tunguska Event
The Tunguska event was a large explosion of between 3 and 50 TNT equivalent, megatons that occurred near the Podkamennaya Tunguska River in Yeniseysk Governorate (now Krasnoyarsk Krai), Russia, on the morning of 30 June 1908. The explosion over the sparsely populated East Siberian taiga felled an estimated 80 million trees over an area of of forest, and eyewitness accounts suggest up to three people may have died. The explosion is attributed to a meteor air burst, the atmospheric explosion of a stony asteroid about wide. The asteroid approached from the east-south-east, probably with a relatively high speed of about . Though the incident is classified as an impact event, the object is thought to have exploded at an altitude of rather than hitting the Earth's surface, leaving no impact crater. The Tunguska event is the largest impact event on Earth in recorded history, though List of impact craters on Earth, much larger impacts are believed to have occurred in prehistoric ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Astronomical Union
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 development through global cooperation. It was founded on 28 July 1919 in Brussels, Belgium and is based in Paris, France. The IAU is composed of individual members, who include both professional astronomers and junior scientists, and national members, such as professional associations, national societies, or academic institutions. Individual members are organised into divisions, committees, and working groups centered on particular subdisciplines, subjects, or initiatives. the Union had 85 national members and 12,734 individual members, spanning 90 countries and territories. Among the key activities of the IAU is serving as a forum for scientific conferences. It sponsors nine annual symposia and holds a triannual General Assembly that sets policy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meteoroid - Meteor (Bolide) - Meteorite
A meteoroid ( ) is a small rocky or metallic body in outer space. Meteoroids are distinguished as objects significantly smaller than ''asteroids'', ranging in size from grains to objects up to wide. Objects smaller than meteoroids are classified as ''micrometeoroids'' or ''space dust''. Many are fragments from comets or asteroids, whereas others are collision impact debris ejected from bodies such as the Moon or Mars. The visible passage of a meteoroid, comet, or asteroid entering Earth's atmosphere is called a meteor, and 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. An estimated 25 million meteoroids, micrometeoroids and other space debris enter Earth's atmosphere each day, which results in an estimated 15,000 tonnes of that material entering the atmosphere each year. A ''meteorite'' is the remains of a meteoroid that has survived the ablation of its surface material du ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comet
A comet is an icy, small Solar System body that warms and begins to release gases when passing close to the Sun, a process called outgassing. This produces an extended, gravitationally unbound atmosphere or Coma (cometary), coma surrounding the nucleus, and sometimes a Comet tail, tail of gas and dust gas blown out from the coma. These phenomena are due to the effects of solar radiation and the outstreaming solar wind plasma acting upon the nucleus of the comet. Comet nuclei range from a few hundred meters to tens of kilometers across and are composed of loose collections of ice, dust, and small rocky particles. The coma may be up to 15 times Earth's diameter, while the tail may stretch beyond one astronomical unit. If sufficiently close and bright, a comet may be seen from Earth without the aid of a telescope and can Subtended angle, subtend an arc of up to 30° (60 Moons) across the sky. Comets have been observed and recorded since ancient times by many cultures and religion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asteroid
An asteroid is a minor planet—an object larger than a meteoroid that is neither a planet nor an identified comet—that orbits within the Solar System#Inner Solar System, inner Solar System or is co-orbital with Jupiter (Trojan asteroids). Asteroids are rocky, metallic, or icy bodies with no atmosphere, and are broadly classified into C-type asteroid, C-type (carbonaceous), M-type asteroid, M-type (metallic), or S-type asteroid, S-type (silicaceous). The size and shape of asteroids vary significantly, ranging from small rubble piles under a kilometer across to Ceres (dwarf planet), Ceres, a dwarf planet almost 1000 km in diameter. A body is classified as a comet, not an asteroid, if it shows a coma (tail) when warmed by solar radiation, although recent observations suggest a continuum between these types of bodies. Of the roughly one million known asteroids, the greatest number are located between the orbits of Mars and Jupiter, approximately 2 to 4 astronomical unit, AU ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
