Search results
Results from the WOW.Com Content Network
The 60-tonne, 2.7 m-long (8.9 ft) Hoba meteorite in Namibia is the largest known intact meteorite.[1]A meteorite is a rock that originated in outer space and has fallen to the surface of a planet or moon.
Meteorite classification may indicate that a "genetic" relationship exists between similar meteorite specimens. Similarly classified meteorites may share a common origin, and therefore may come from the same astronomical object (such as a planet, asteroid, or moon) known as a parent body.
Widmanstätten patterns, also known as Thomson structures, are figures of long phases of nickel–iron, found in the octahedrite shapes of iron meteorite crystals and some pallasites. Iron meteorites are very often formed from a single crystal of iron-nickel alloy, or sometimes a number of large crystals that may be many meters in size, and ...
Octahedrites are the most common structural class of iron meteorites. The structures occur because the meteoric iron has a certain nickel concentration that leads to the exsolution of kamacite out of taenite while cooling.
Fossil meteorite – a meteorite that was buried under layers of sediment before the start of the Quaternary period. Some or all of the original cosmic material has been replaced by diagenetic minerals. [3]: 320 (It is, however, not a fossil). Fusion crust – a coating on meteorites that forms during their passage through the atmosphere.
A meteorite is a portion of a meteoroid or asteroid that survives its passage through the atmosphere and hits the ground without being destroyed. [77] Meteorites are sometimes, but not always, found in association with hypervelocity impact craters; during energetic collisions, the entire impactor may be vaporized, leaving no meteorites.
CM chondrites are a group of chondritic meteorites which resemble their type specimen, the Mighei meteorite. The CM is the most commonly recovered group of the 'carbonaceous chondrite' class of meteorites, though all are rarer in collections than ordinary chondrites.
Hexahedrites are a structural class of iron meteorite. They are composed almost exclusively of the nickel – iron alloy kamacite and are lower in nickel content than the octahedrites . [ 1 ] The nickel concentration in hexahedrites is always below 5.8% and only rarely below 5.3%.