Nedagolla meteorite, Vizianagaram District, Andhra Pradesh, Indiai

Regional Level Types
Nedagolla meteorite	Meteorite Fall Location
Vizianagaram District	District
Andhra Pradesh	State
India	Country

Anomalous Iron (I-ung)[Ni-poor ataxite]
Fall, 23 Jan 1870; 4.5 kg


A fireball traveling from north to south, accompanied by a thunderous detonation and subsequent rumblings, was observed to fall as it created a 50 cm deep hole while apparently injuring several people. The recovered mass [16 x 11 x 6 cm] was first taken to a local temple, but was subsequently placed under control of the British colonial authorities. The fallen mass of Fe-Ni metal (~6% Ni) is clearly meteoritic, but it is quite unusual in several ways — texturally, mineralogically, and geochemically. Severe pre-terrestrial shock-melting followed by almost immediate cooling has left a very poorly defined 'dendritic' or ataxic mineralogical structure. Kamacite is revealed by X-ray diffraction, microscopic traces of taenite, and disordered martensite are common, but there are few signs of the usual hexahedral or octahedral patterns found in most irons. Minor amounts of reduced graphite, cohenite, and daubréelite are also observed. However, both schreibersite and the usually ubiquitous troilite were not observed (Cf. Buchwald, 1975). Geochemical anomalies include dissolved Si (0.14%) in the Fe-Ni metal and, at the time, the lowest observed Ge content of any iron meteorite. Fe-oxides (magnetite & wüstite) are found in the relatively intact fusion crust.

By the end of 2014, over 11% of all fully classified irons have been classified as 'ungrouped' [117 of over 1000]. The ungrouped irons clearly do not belong to any of the dozen or so classified groups and are believed to fragments of perhaps 20-50 disrupted asteroidal cores. However, only 4 of these ungrouped irons are witnessed falls. Theoretically, such relatively pristine extraterrestrial material should be easier to understand than the usual weathered iron meteorite recovered years or even centuries after its unrecorded fall. Disentangling the history of the Nedagolla skyfall, however, may provide even more conundrums than the average iron meteorite — weathered or newly fallen.

Most of the original mass (~4 kg) is at Natural History Museum in London.

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References