Kosice - 200g

History: On February 28, 2010, at 22:24:46 UT a bright fireball appeared over central-eastern Slovakia. The cloudy and rainy weather prevented images been taken by the European Fireball Network or the Slovak Video Network. However, the fireball flash was recorded at six Czech and one Austrian fireball stations (P. Spurny, CzAS). The bolide reached at least -18 maximum brightness. Sonic booms were recorded at seven seismic stations in Slovakia, Hungary, and Poland (P. Kalenda, CzASO). The fall area was computed on the basis of two records of the surveillance cameras operating in Hungary (A. Igaz, HAA) by J. Borovicka (CzAS). The first meteorite (27.2 g) was found March 20 by J. Toth (CUB) to the northwest of the city of Košice (eastern Slovakia). Pieces were found by teams led by the Faculty of the Mathematics, Physics and Informatics, CUB and SAS. The largest stone weighs 2.2 kg. The finders include Juraj Toth, Diana Buzova, Marek Husarik, Tereza Krejcova, Jan Svoren, Julo Koza, David Capek, Pavel Spurny, Stanislav Kaniansky, Eva Schunova Marcel Skreka, Dusan Tomko, Pavol Zigo, Miroslav Seben, Jiri Silha, Leonard Kornos, Marcela Bodnarova, Peter Veres, Jozef Nedoroscik, Zuzana Mimovicova, Zuzana Krisandova, Jaromir Petrzala, Stefan Gajdos, Tomas Dobrovodsky, Peter Delincak, Zdenko Bartos, Ales Kucera, Jozef Vilagi.

Physical characteristics: Seventy-seven black stones with a thin fusion crust with the total weight 4.3 kg in the range of 0.5 g to 2.2 kg.

Petrography: Classification (D. Ozdin and P. Uher, CUB; J. Haloda, CzGS; P. Konecny, SGUDS) Thin sections show a recrystallized fine-grained granular texture. Chondrule commonly indistinct. Planar fractures in olivine and undulatory extinction of olivine and albite as well as opaque shock veins and locally melt pockets indicate a shock of S3.

Geochemistry: Olivine (Fa_18.6) and low-Ca pyroxene (Fs_16.6). Also present are diopside (Fs₆Wo₄₆), augite (Fs_8-15Wo_26-43), albite (Ab₈₂An₁₂Or₆), chromite, chlorapatite, merrillite, troilite, kamacite, taenite and tetrataenite.

Classification: Ordinary chondrite, H5 (S3). Weathering grade is W0.

Specimens: 2190.0 g, 315.9 g, 249.0 g, 210.5 g, 193.6 g, 106.8 g; SAS; CUB.