Meteorite definitions and example sentences on Wordnik

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Definitions (5)

American Heritage Dictionary (1)

noun A stony or metallic mass of matter that has fallen to the earth's surface from outer space.

Century Dictionary (2)

A mineral or metallic mass of extraterrestrial origin, or which, to use the common expression, has “fallen from the heavens.” Bodies of this kind were formerly often called aerolites, but meteorite is now their generally accepted name among scientific men. The fall of meteorites upon the earth is a by no means infrequent occurrence, and records of such events date back to many centuries before the present era. Traditions point to the very early use of meteoric iron for the manufacture of weapons; and it is also known that meteorites were not unfrequently the objects of worship in various parts of the world. In spite of this, the fall of rocks or metals from the heavens seemed to be so improbable an event that full credence was not given by scientific men to stories of such occurrences until about the beginning of the present century, when, several falls having taken place (at. Barbotan, France, 1790; Siena, 1794; Wold Cottage, Yorkshire, Eng., 1795; Salés, France, 1798; Benares, 1798; L'Aigle, France, 1803), the details of some of which were thoroughly investigated, a further denial of their genuineness became impossible. From the time of the fall at L'Aigle all doubt in the matter was abandoned. There are now several collections of meteorites, each of which contains specimens of between 300 and 400 different falls, and the whole number known is not far from 400, although it is by no means the case with all these occurrences that the specimens were seen to fall; many of them have been found on the earth's surface, but have been recognized as being extraterrestrial by their peculiar appearance and composition. The most important facts with regard to meteorites maybe concisely stated as follows: They have not been found to contain any element not known to occur on the earth; they have furnished no evidence of the existence of life on the body or bodies of which they originally formed a part; they bear no indications of having been formed in the presence of water, or of the existence of water beyond the earth's atmosphere in the regions from which they came; they do exhibit abundant evidence of having had what geologists would call an “igneous origin” they are never granitic in character, but resemble very closely certain volcanic rocks of not infrequent occurrence, with this difference, that in the case of the meteorites the iron associated with the silicated combinations exists in the metallic form, while in the terrestrial volcanic rocks it is, with rare exceptions, oxidized. Furthermore, meteorites, almost, without exception, show a certain family resemblance; so that it is necessary to admit, either that they all originally formed a part of one celestial body, or else that, having come from various members of the solar system, or from other systems, these have a wonderful resemblance to each other and to the earth itself. The most obvious division of meteorites is into metallie and stony, but the passage from one class to the other is by no means an abrupt one. All metallic meteorites agree in that the predominating metal is iron, with which nickel is almost invariably associated; indeed, it has not been proved that there is any meteoric iron entirely free from that metal. With the nickel cobalt is almost always found, as is the ease in terrestrial combinations. Tin and copper are also frequently found in meteorites in small quantity. The precious metals have not been detected in them. Meteorites composed almost entirely of metallic (niekeliferous) iron, forming a nearly homogeneous mass, have been denominated siderolites. These, however, almost always contain irregular nodular masses of pyrrhotite, schreibersite (phos-phuret of iron and nickel), either one or both. and occasionally of graphite. In a large proportion of the meteoric irons, etching the polished surface with an acid develops the so-called “Widmannstättian figures.” The development of these figures on the polished surface of a mass of iron found upon the earth's surface, and in regard to the time of whose fall nothing was known, was formerly considered to be sufficient evidence of the celestial origin of such a mass, especially if, in addition, the presence of nickel could be shown by chemical analysis. While most of the metallic masses thus referred have almost certainly been correctly classed among the meteorites, there may be cases in which such reference has not been justifiable, since it is now known that all celestial irons do not give the Widmannstattian figures, while the iron found in large quantity and over a wide area, associated with and embedded in basalt, near Ovifak in Greenland, contains nickel, and gives, when etched, figures which have generally been considered as Widmannstattian, although others have denied that they could properly be so denominated. The terrestrial origin of the Ovifak iron is, however, now generally admitted, although for a considerable time after its discovery this was not the case. The wide extent of the area over which this iron occurs, and its peculiarly intimate association with the minerals of which the basalt is made up, forbid the idea that the metal could have fallen from above into lava in process of eruption, which was at first the favorite theory of its origin. Next in order to the siderolites come the pallasites, so named from the fact that a large meteorite of this class was in 1772 discovered in Siberia by the distinguished traveler Pallas. Under the name of pallasiteare comprehended those meteorites which consist of a spongy or vesicular mass of iron, the cavities of which are in most cases partly or entirely filled with olivin, with which various other minerals are frequently associated, enstatite and bronzite being the most common, while chromite is of not infrequent occurrence. Both siderolites and pallasites belong to the class of metallic meteorites. By far the larger part of the stony meteorites are included under the designation of chondrites. In these the iron is distributed in fine particles through a more or less intimate mixture of silicates, with which chromite and magnetic pyrites are frequently associated, the silicates being chiefly olivin and bronzite. The name chondrite has reference to the fact that in this class of meteorites the material of which they are composed occurs in the form of rounded grains (chondri). The chondritic meteorites have, however, a quite varied structure, in some few cases passing into a breccia; they have been divided into numerous subgroups in accordance with these structural variations. Most of the stony meteorites contain iron disseminated through their mass in grains or nodules; but there are a few which are destitute of such metallic particles. There are also a few stony meteorites which do not exhibit any traces of a chondritic structure: the minerals of which these are made up do not, however, dilfer very essentially from those occurring in the chondrites. There are also a few very anomalous meteorites which contain carbonaceous matter associated with the stony chondritic material. This carbon is not graphitic, but is combined with hydrogen and oxygen, the product resembling to a certain extent that resulting from the decay of organic matter, but no traces of vegetable tissue have been discovered in these carbonaceous meteorites, which are only five or six in number. One or two interesting facts remain to be mentioned. The first is that since the phenomena of meteorites began to be observed and studied there have been extremely few falls of metallic meteorites. Of all the meteoric irons in the various collections, those of Hraschina in Austria (1751), of Dickson county, Tennessee (1855), of Braunau in Bohemia (1847), and a few others (in all probably about nine), are the only ones positively known to have fallen; all the others are considered meteoric on account of their peculiar appearance and chemical composition. The observed falls of stony meteorites, on the other hand, are numerous. Another remarkable fact is that all the meteorites which are known to have fallen are of inflnitesimally small size as compared with the earth. In the fall of L'Aigle some 2,000 to 3,000 stones were estimated to have reached the earth, and of these the largest weighed only seven or eight pounds. The largest meteorites of which the fall was observed are that of Ensisheim (1492), which weighed about 280 pounds, that of Juvinas (1821), 242 pounds, and that of Emmett county, Iowa (1879), when a considerable number of stones fell, the largest of them weighing 437 pounds. Some masses of iron believed to be meteorites, the date of whose fall is unknown, are much larger than this, but still utterly insignificant in size, not only as compared with the earth or its satellite, but even with the smallest celestial body of which anything is definitely known, namely the outer satellite of Mars, which has been estimated at from five to twenty-miles in diameter. The mass of iron on the river Bendegó in Brazil has been variously estimated at from seven to ten tons in weight; that of Tucuman (Campo del Cielo) is said to weigh fifteen tons. The Santa Caterina iron appears to be still larger, having been estimated at twentyfive tons; but doubts have been expressed as to whether this is really of celestial origin.
Neumann's lines structural lines described by J. G. Neumann as occurring in the Braunau meteorite.

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So if you got run over by a truck or hit by a meteorite, your farlie would sense this and automatically pop out and take over, after prudently making a farlie of itself. — F ;SF - vol 105 issue 04-05 - October-November 2003
A wave produced by a meteorite is known as a tsunami. — F ;SF - vol 105 issue 04-05 - October-November 2003
The meteorite, according to the locals, descended in the open ground at 11.25 pm. — Signs of the Times
Furthermore, the team determined that the meteorite was what astronomers refer to as a polymic ureilite, in other words, a very rare and unusually fragile, dark rock. — News and Features - NASA's Jet Propulsion Laboratory
Forgiving the scientific cartoon fact that Superman is an alien (who grew up on Earth), and that the possibility of his DNA being compatible with humans is about as likely as being hit by a green meteorite, the science fiction science doesn't make sense. — The Toque

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