In 1772, German naturalist Peter Pallas encountered a 700kg lump of metal about 145 miles south of Krasnojarsk, Russia. One of the most significant meteorites in the Museum's collection is a 1.7kg mass from the Krasnojarsk meteorite. Tektites are small (sized from a few millimetres to centimetres) glassy bodies that form during meteorite impacts, when they are thrown up from the Earth. These include approximately 60 iron, 150 stony and 20 stony-iron meteorites, as well as a small selection of tektites. The Museum holds a small but significant collection of over 200 meteorites. ‘Falls’ are those meteorites that are seen to fall, whereas ‘finds’ are discovered without observing the fall. Meteorites are categorised as ‘falls’ or ‘finds’, and are named after the places they are discovered. Regmaglypts (thumb-shaped impressions) may also form on the surfaces of meteorites due to their interaction with the Earth’s atmosphere as vortices ablate material away. As meteorites enter the Earth’s atmosphere, frictional heating and melting results in the formation of a black fusion crust on their surfaces, usually less than a millimetre thick. Disruptions to the asteroid belt by collisions or gravitational perturbations can send material towards the Earth. The majority of meteorites on Earth come from the asteroid belt, a band of planetary debris orbiting the Sun between Mars and Jupiter. Meteorites are unusual and rare rocks of extraterrestrial origin and are divided broadly into three types: stony, stony-iron and iron.
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