Meteorite - Wikipedia. This article is about debris from space that survives impact with the ground. For popular applications, see Falling star. For the fictional superhero in the Marvel Comics universe, see Meteorite (comics). Not but the meteor may have shown itself at that point, burning duskily through a veil of cloud, but with no such shape as his guilty imagination gave it, or, at least, with so little definiteness, that another's guilt might have seen another symbol in it. ITunes is the world's easiest way to organize and add to your digital media collection. We are unable to find iTunes on your computer. To download the free app Meteor by Weng Shao-Hang, get iTunes now. Do you already have iTunes? Click I Have iTunes to open it now. Find Meetups about Meteor and meet people in your local community who share your interests. Find out what's happening in Meteor Meetup groups around the world and start. Homophone: meatier Noun . Meteor is a set of new technologies for building top-quality web apps in a fraction of the time. Search Meteor Videos Playlists Channels Discussion About Home Trending History Best of YouTube Music Sports. Radiant of the Perseid meteor shower. The Perseids seem to come from the direction of the Perseus, a constellation in the north-eastern part of the sky Based on NASA illustration When Can I See the Perseids? The Perseid meteor shower, one of the brighter. See a rich collection of stock images, vectors, or photos for meteor you can buy on Shutterstock. Explore quality images, photos, art & more. Happy little asian girl kid in astronaut suit doodle chalk board drawing universe out of earth planet school green. A meteorite is a solid piece of debris from an object, such as a comet, asteroid, or meteoroid, that originates in outer space and survives its passage through the Earth's atmosphere and impact with the Earth's surface or that of another planet. When the object enters the atmosphere, various factors like friction, pressure, and chemical interactions with the atmospheric gases cause it to heat up and radiate that energy. It then becomes a meteor and forms a fireball, also known as a shooting/falling star; astronomers call the brightest examples . For geologists, a bolide is a meteorite large enough to create a crater. Meteorites that are recovered after being observed as they transit the atmosphere or impact the Earth are called meteorite falls. All others are known as meteorite finds. Modern classification schemes divide meteorites into groups according to their structure, chemical and isotopic composition and mineralogy. Meteorites smaller than 2 mm are classified as micrometeorites. Extraterrestrial meteorites are such objects that have impacted other celestial bodies, whether or not they have passed through an atmosphere. They have been found on the moon. In cases where many meteorites were found in one place, the name may be followed by a number or letter (e. Allan Hills 8. 40. Dimmitt (b)). The name designated by the Meteoritical Society is used by scientists, catalogers, and most collectors. Fall phenomena. Usually, five to ten a year are observed to fall and are subsequently recovered and made known to scientists. Instead, they typically arrive at the surface at their terminal velocity and, at most, create a small pit. The kind of crater will depend on the size, composition, degree of fragmentation, and incoming angle of the impactor. The force of such collisions has the potential to cause widespread destruction. Examples of craters caused by iron meteoroids include Barringer Meteor Crater, Odessa Meteor Crater, Wabar craters, and Wolfe Creek crater; iron meteorites are found in association with all of these craters. In contrast, even relatively large stony or icy bodies like small comets or asteroids, up to millions of tons, are disrupted in the atmosphere, and do not make impact craters. Very large stony objects, hundreds of meters in diameter or more, weighing tens of millions of tons or more, can reach the surface and cause large craters, but are very rare. Such events are generally so energetic that the impactor is completely destroyed, leaving no meteorites. Various colors have been reported, including yellow, green, and red. Flashes and bursts of light can occur as the object breaks up. Explosions, detonations, and rumblings are often heard during meteorite falls, which can be caused by sonic booms as well as shock waves resulting from major fragmentation events. These sounds can be heard over wide areas, with a radius of a hundred or more kilometers. Whistling and hissing sounds are also sometimes heard, but are poorly understood. Following passage of the fireball, it is not unusual for a dust trail to linger in the atmosphere for several minutes. They can be sculpted into various shapes during this process, sometimes resulting in shallow thumbprint- like indentations on their surfaces called regmaglypts. Meteor - Meteor, the JavaScript App Platform. Important note about Git submodules! This repository uses Git submodules. If you clone without the --recursive flag, re-fetch with git pull or experience 'Depending on unknown package' errors, run the following in the. If the meteoroid maintains a fixed orientation for some time, without tumbling, it may develop a conical . As it decelerates, eventually the molten surface layer solidifies into a thin fusion crust, which on most meteorites is black (on some achondrites, the fusion crust may be very light colored). On stony meteorites, the heat- affected zone is at most a few mm deep; in iron meteorites, which are more thermally conductive, the structure of the metal may be affected by heat up to 1 centimetre (0. Reports vary; some meteorites are reported to be . The area over which a meteorite shower falls is known as its strewn field. Strewn fields are commonly elliptical in shape, with the major axis parallel to the direction of flight. In most cases, the largest meteorites in a shower are found farthest down- range in the strewn field. Only about 6% of meteorites are iron meteorites or a blend of rock and metal, the stony- iron meteorites. Modern classification of meteorites is complex. The review paper of Krot et al. These particles, or chondrules, are composed mostly of silicate minerals that appear to have been melted while they were free- floating objects in space. Certain types of chondrites also contain small amounts of organic matter, including amino acids, and presolar grains. Chondrites are typically about 4. Like comets, chondritic asteroids are some of the oldest and most primitive materials in the solar system. Chondrites are often considered to be . Most achondrites are also ancient rocks, and are thought to represent crustal material of differentiated planetesimals. One large family of achondrites (the HED meteorites) may have originated on the parent body of the Vesta Family, although this claim is disputed. Two small groups of achondrites are special, as they are younger and do not appear to come from the asteroid belt. One of these groups comes from the Moon, and includes rocks similar to those brought back to Earth by Apollo and Luna programs. The other group is almost certainly from Mars and constitutes the only materials from other planets ever recovered by humans. About 5% of meteorites that have been seen to fall are iron meteorites composed of iron- nickelalloys, such as kamacite and/or taenite. Most iron meteorites are thought to come from the cores of planetesimals that were once molten. As with the Earth, the denser metal separated from silicate material and sank toward the center of the planetesimal, forming its core. After the planetesimal solidified, it broke up in a collision with another planetesimal. Due to the low abundance of iron meteorites in collection areas such as Antarctica, where most of the meteoric material that has fallen can be recovered, it is possible that the percentage of iron- meteorite falls is lower than 5%. This would be explained by a recovery bias; laypeople are more likely to notice and recover solid masses of metal than most other meteorite types. The abundance of iron meteorites relative to total Antarctic finds is 0. They are a mixture of iron- nickel metal and silicate minerals. One type, called pallasites, is thought to have originated in the boundary zone above the core regions where iron meteorites originated. The other major type of stony- iron meteorites is the mesosiderites. Tektites (from Greek tektos, molten) are not themselves meteorites, but are rather natural glass objects up to a few centimeters in size that were formed. A few researchers have favored tektites originating from the Moon as volcanic ejecta, but this theory has lost much of its support over the last few decades. Meteorite chemistry. Pyrimidine, like polycyclic aromatic hydrocarbons (PAHs), the most carbon- rich chemical found in the Universe, may have been formed in red giants or in interstellar dust and gas clouds, according to the scientists. An observed fall. Most meteorite falls are recovered on the basis of eyewitness accounts of the fireball or the impact of the object on the ground, or both. Therefore, despite the fact that meteorites fall with virtually equal probability everywhere on Earth, verified meteorite falls tend to be concentrated in areas with high human population densities such as Europe, Japan, and northern India. A small number of meteorite falls have been observed with automated cameras and recovered following calculation of the impact point. The first of these was the P. The images were used both to determine the location of the stones on the ground and, more significantly, to calculate for the first time an accurate orbit for a recovered meteorite. Following the Pribram fall, other nations established automated observing programs aimed at studying infalling meteorites. One of these was the Prairie Network, operated by the Smithsonian Astrophysical Observatory from 1. US. This program also observed a meteorite fall, the Lost City chondrite, allowing its recovery and a calculation of its orbit. It too recovered a single meteorite, Innisfree, in 1. More than 8. 0% of these were iron and stony- iron meteorites, which are easily distinguished from local rocks. To this day, few stony meteorites are reported each year that can be considered to be . The reason there are now more than 3. Harvey H. Nininger that meteorites are much more common on the surface of the Earth than was previously thought. The Great Plains of the US. Between the late 1. The result was the discovery of over 2. After the discovery of a few meteorites in 1. Ivan Wilson. In total, nearly 1. In the area of the finds, the ground was originally covered by a shallow, loose soil sitting atop a hardpan layer. During the dustbowl era, the loose soil was blown off, leaving any rocks and meteorites that were present stranded on the exposed surface. Microscopically, the features were initially interpreted as fossils of bacteria- like lifeforms. It has since been shown that similar magnetite structures can form without the presence of microbial life in hydrothermal systems. In 1. 96. 9, the 1. Japanese Antarctic Research Expedition found nine meteorites on a blue ice field near the Yamato Mountains. With this discovery, came the realization that movement of ice sheets might act to concentrate meteorites in certain areas. After a dozen other specimens were found in the same place in 1. Japanese expedition was launched in 1. This team recovered nearly 7. European teams, starting with a consortium called . A Korean program (KOREAMET) was launched in 2. For more information see the article by Harvey (2.
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