Tambakwatu (meteorite)

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Coordinates: 7 ° 45 '0 "  S , 112 ° 46' 12"  O Tambakwatu is a meteorite that struck near the village of Tambakwatu in1975and was named after the place where it was found. The village is located in the Purwosari District in the administrative district of Pasuruan in the Indonesian province of Jawa Timur (East Java).

history

The meteorite impact was observed just before midnight on February 14, 1975 near the village of Tambakwatu. The 10.5 kilogram stone fell from the sky in one piece. The Jakarta Planetarium and Observatory staff later added the meteorite to the planetarium's inventory.

As of 2000, 617 grams of the meteorite were in the Jakarta Planetarium and Observatory, 58 grams in the National Museum of Natural History in Washington, DC, and another fragment in the collection of meteorite collector James Maxime DuPont (1912-1991) in Palatine , Illinois .

Appearance and classification

The stone meteorite is a typical recrystallized olivine - hypersthene - chondrite of class L6 with a weight of 10.5 kilograms. The stone is gray, veined and has many iron oxide stains.

composition

The Washington Smithsonian Institution was given 700 grams of the meteorite for material testing, 10 grams of which were petrographically analyzed. The Tambakwatu meteorite consists of 87 percent silicates , 8 percent metal, 4.5 percent troilite and 0.5 percent chromite . The silicates are 52.0 percent as olivine, 27.2 percent as hypersthenes, 8.2 percent as albite and 7.8 percent as diopside . In the case of silicates, there are also 5.3 percent troilite, 0.9 percent anorthite and 0.7 percent orthoclase .

The more precise composition of the meteorite fragment was determined as follows: 44.9 percent is silicon dioxide (SiO 2 ), 28.1 percent is magnesium oxide (MgO), and 16.4 percent is iron (II) oxide (FeO). The following components are below ten percent: 5.28 percent iron (II) sulfide (FeS), 2.3 percent calcium oxide (CaO), 2.03 percent aluminum oxide (Al 2 O 3 ), 0.96 percent sodium oxide (Na 2 O), 0.18 percent nickel (Ni) and 0.13 percent potassium oxide (K 2 O).

Web links

  • Tambakwatu. Meteorological Bulletin Database, accessed November 29, 2019 .

Individual evidence

  1. ↑ Tambakwatu in Meteoritical Bulletin No. 58, 1980, p. 240 (English)
  2. ↑ Monica M. Grady (Ed.): Catalog of Meteorites . 5th edition, Cambridge University Press, Cambridge 2000, ISBN 0-521-66303-2 . P. 482 (English)
  3. ↑ Kurt Fredriksson, Joy Miller, Joseph Nelen, Sukartadiredja Darsa: The Tambakwatu Chondrite . Meteoritics & Planetary Science Vol. 16, No. 1, pp. 77 to 81, March 31, 1981, accessed November 29, 2019 (English).