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Chondryt Antonin – pierwszy polski meteoryt ze zrekonstruowaną orbitą wokółsłoneczną. Raport z klasyfikacji i rejestracji oraz propozycje działań mogących wzbogacić kolekcję polskich meteorytów

Krzesińska Agata, Tymiński Zbnigniew, Maćkowska Roksana

Przegląd Geologiczny

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2023

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Vol. 71, nr 7

372--385

EN

On July 15, 2021, a bright fireball was registered over Poland and it led to a meteorite fall near the towns of Antonin and Mikstat, on the border of the Greater Poland and Lower Silesia voivodeships. Soon after registration of the bolide, a meteorite fragment was found. Observation of the fireball's trajectory helped to reconstruct the pre-atmospheric parameters of the meteoroid, such as the orbit inclination or eccentricity (Shrbený et al., 2022). Additionally, finding of the meteorite fragment enabled petrographic research and reconstruction of the thermal and collisional history of meteorite'sparent body. The Antonin meteorite is the first Polish meteorite with the reconstructed pre-atmospheric orbit and, atthe moment, one of only fifty in theworld. It is an L5 ordinary chondrite (Shrbený et al., 2022; Krzesińska, 2023). Here we present a report on the classification and registration process of the Antonin meteorite. Registration included measurements of cosmogenic isotope, necessary to prove the connection of the meteorite with the observed bolide. The specimen was found during the private expedition, so no direct proof existed for find in the predicted fall area. Cosmogenic isotope study allowed to assessing the time of meteorite fall, which matched the fireball event. Classification included petrographic and mineralogical analysis of the rock. The fall and find circumstances of Antonin allowed us to reflect on the lack of awareness of the Polish society regarding meteorites. Such unawareness is also seen when the whole collection of Polish meteorites is statistically analysed. We present such analysis at the end of the paper, and conclude that many meteorite falls in Poland must be unnoticed. Additionally, inability of citizens to recognize a meteorite, especially a chondrite, causes that many of these rocks remain unrecovered. The aim of this paper is to inspire the reader to pay attention to falls of meteorites, and to look for potential meteorite rocks. In final, we encourage the readers to get involved in activities of fireball networks and to take part in meteorite recovery trips.

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The meteorite fall near Boumdeid, Mauritania, from September 14, 2011

Buhl S., Toueirjenne C., Hofmann B., Laubenstein M., Wimmer K.

Meteorites

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2014

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Vol. 3, No. 1-2

5--18

EN

On the evening of September 14, 2011 at 21:00 GMT a bright bolide was observed by hundreds of eyewitnesses in the area north and west of the town of Kiffa, in the department of Assaba, in south Mauritania. A terminal fragmentation and sound phenomena were observed near the end point of the trajectory. At least one mass of 3.5 kg was observed to impact and recovered the morning after the fall near Boumdeid (or Bou Mdeid), around 60 km north of Kiffa. Subsequently a large number of eyewitness accounts were recorded and mapped by GPS. The present paper provides a scenario for the trajectory of the Boumdeid (2011) meteorite based on the available parameters and wind data at the relevant altitudes. In addition the paper presents the results of the mineralogical and chemical analysis of the recovered meteorite which is consistent with a classification as ordinary chondrite of type L6, shock stage S2, and a weathering grade of W0. Following its analysis and classification, the meteorite was published under the official name Boumdeid (2011) in Meteoritical Bulletin, no. 100, MAPS 49(8), (2014). Gamma ray spectroscopy was conducted 84 days after the fall and the detection of short-lived radionuclides such as 56Co and 46Sc confirmed the recency of the event. Derived from the data of 60Co, 54Mn and 22Na the approximate preatmospheric radius of the meteorite body was 10–20cm. The report is also intended to serve as a case example for post-event data recovery and trajectory reconstruction in areas not covered by sky-camera networks and with limited scientific infrastructure.

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Sołtmany meteorite

Karwowski Ł.

Meteorites

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2012

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Vol. 2, No. 1-2

15--30

EN

This paper presents the results of a mineralogical and petrological study of the Sołtmany meteorite, which fell on April 30, 2011 in northern Poland. The meteorite was found almost immediately after it fell and has been little altered by weathering. Sołtmany is not the only observed fall of an L6 chondrite over Europe in the past few years. The preceding fall of this type, Jesenice (Slovenia), was also witnessed in April of 2009. However, it was not until several weeks after the fall that the first specimen of Jesenice was found, whereas Sołtmany was collected after a few minutes and submitted for analysis within a couple of days. The author presents mineral and petrographic features and chemical characteristics of mineral phases in Sołtmany. The mineral components are represented by metallic phases (kamacite, taenite, tetrataenite, native copper), as well as chromite, olivine, low and high-calcium pyroxene, feldspar, chlorine-bearing apatite, and merrillite. This study also describes the texture of the meteorite and takes notice of a low number of preserved chondrules and the presence of oval chondrule like areas, which exhibit a metamorphosed, recrystallized texture. Sołtmany was classified as an L6 ordinary chondrite with a weathering grade of W0. A shock stage S2 was determined on the basis of undulose extinction and lack of planar fractures in olivine crystals.

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Bulk chemical composition of Sołtmany chondrite

Przylibski T. A., Łuszczek K.

Meteorites

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2012

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Vol. 2, No. 1-2

31--37

EN

The authors examined the bulk chemical composition of the Sołtmany chondrite which fell on April 30th, 2011 in Northern Poland. Based on the analysis of 47 elements, it was concluded that Sołtmany is representative of L-type of ordinary chondrites. However, compared to the average values observed in other L-type ordinary chondrites, Sołtmany displays higher content of Ni, P, Cd, Pb, and As. The Ni and P content closely resembles typical values for H-type ordinary chondrites. Furthermore, Sołtmany displays other distinct properties including very low Zn content and lower contents of Mo and Zr than the average values found in other L-type ordinary chondrites. Consistent with other L-type ordinary chondrites, the absolute content of REE in Sołtmany is higher than that of CI-type carbonaceous chondrites while the REE trend lines for both Sołtmany and CI-chondrites are similar. Due to similar times of year of when both falls took place and the proximity of their strewn fields, the chemical composition of Sołtmany was compared with that of Jesenice, an L6 ordinary chondrite which fell on April 9th, 2009 in Europe. The analysis led to a conclusion that Sołtmany and Jesenice are not launch-paired. Nevertheless, even though they do not represent fragments of the same meteoroid, their origin on a common parent body (an asteroid – planetesimal) cannot be conclusively ruled out on the sole basis of their bulk chemical composition.

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Account of circumstances surrounding the fall of a meteorite in Sołtmany village

Woźniak B., Woźniak M.

Meteorites

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2012

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Vol. 2, No. 1-2

9--14

EN

Report from the place of the event the fall of a meteorite in the village of Sołtmany

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Dating of the reo site (Island of Saaremaa, Estonia) with silicate and iron microspherules points to an exact age of the fall of the Kaali meteorite

Moora T., Raukas A., Stankowski W. T. J.

Geochronometria

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2012

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Vol. 39, no. 4

262-267

EN

Pollen analyses and radiocarbon dates from the bottom sediments in the Kaali main crater suggested that the crater group is at least 4000-5000 years old. Investigations of silicate impact micro-spherules in surrounding mires (Raukas et al. 1995) put the age about 7500-7600 yr BP. Recently we found both silicate and iron microspherules from organic sediments below well-dated beach ridge in Reo site what supports the conclusions that the most realistic age of the Kaali craters is 7600š50 14C BP (8335-8537 cal BP) and the meteorite fall was from SSE to NNW.