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EN
I wonder if a description of Morasko meteorite “rainfall” could be found in any medieval chronicles? If Bartoshewitz’s and ‘bolid wielkopolski’ hypothesis’s are only the result of dishonesty of chroniclers and ancient meteorite researchers? A survey of old annals is closing us to the explanation of this catastrophic event from the turn of XIII and XIV century. However, new thesis requires further research.
EN
Iron meteorites are meteorites whose main constituent is iron (Fe) and nickel (Ni), which occur in two forms of Fe-Ni minerals – kamacite and taenite. Since their composition makes them more resistant to shattering (crushing), and they are more challenging to ablate when passing through the atmosphere, they statistically fall in the form of larger lumps than stone or iron-stone meteorites. Their metallic structure and highly high weight make them easy to distinguish from ordinary rocks. The mass of all known iron meteorites is over 500 tons, which is ~89% of known meteorites, but falls of iron meteorites account for only 4.56% of all observed falls (wiki.meteoritica.pl). The ten largest meteorites in the world are iron meteorites! In the past, the term siderite was used to describe iron meteorites. The classification of iron meteorites is based on two criteria. The older method is based on the average nickel content and the crystal structure revealed on cut and etched surfaces, the so-called the Thomson-Widmanstätten patterns. In this division, we distinguish three groups: hexahedrites (4–6 wt.% Ni), the most popular octahedrites (6–12 wt.% Ni) and ataxites (>12 wt.% Ni). The second, more recent method of classifying iron meteorites is based on their chemical composition, in particular the content of trace elements such as germanium (Ge), gallium (Ga), platinum (Pt), arsenic (As), gold ( Au) and iridium (Ir). Another parameter that defines the groups of iron meteorites is their mineral composition. “Indicator” minerals are in the form of various compounds and multiple shapes and sizes: sulfides, phosphides, carbides, nitrides, and silicate inclusions. Trace element content versus nickel content reveals chemical clusters representing the different chemical groups of iron meteorites. Some of the iron meteorites come from the partially differentiated asteroid ruptured at the beginning of forming the iron core and the silicate-rich shell (these are groups IAB and IIE). The remaining meteorites from other groups come from the nuclei of minor differentiated asteroids, shattered in collisions shortly after formation.
PL
Meteoryty żelazne to grupa meteorytów, których głównym składnikiem jest żelazo (Fe) i nikiel (Ni), występujące w dwóch formach stopu Fe-Ni – kamacytu i taenitu. Ponieważ ich skład czyni je bardziej odpornymi na rozbicie (kruszenie) i trudniej ulegają procesowi ablacji przy przelocie przez atmosferę, więc statystycznie spadają one w postaci większych brył niż meteoryty kamienne lub żelazno-kamienne. Ich metaliczna budowa i wyjątkowo duża waga czynią z nich meteoryty łatwe do odróżnienia od zwykłych skał. Masa wszystkich znanych meteorytów żelaznych wynosi ponad 500 ton, co stanowi ~89% masy znanych meteorytów, ale spadki meteorytów żelaznych stanowią już tylko 4,56% wszystkich obserwowanych spadków (Wiki.Meteoritica.pl). Dziesięć największych okazów meteorytów na świecie to meteoryty żelazne! Dawniej na określenie meteorytów żelaznych używano określenia syderyt (siderite). Podziału meteorytów żelaznych dokonuje się według dwóch kryteriów. Starsza metoda bazuje na średniej zawartości niklu i na strukturze krystalicznej ujawniającej się na przeciętych i wytrawionych powierzchniach tzw. figury Thomsona-Widmanstättena. Przy takim podziale wyróżniamy trzy grupy: heksaedryty (hexahedrites) (śr. 4–6wt.% Ni), najpopularniejsze oktaedryty (octahedrites) (śr. 6–12wt.% Ni) oraz ataksyty (ataxites) (>12wt.% Ni). Druga, nowsza metoda klasyfikacji meteorytów żelaznych, opiera się na ich składzie chemicznym, w szczególności na zawartości pierwiastków śladowych (trace elements), takich jak german (Ge), gal (Ga), platyna (Pt), arsen (As), złoto (Au) i iryd (Ir). Drugim parametrem definiującym grupy meteorytów żelaznych jest ich skład mineralny. Minerałami „wskaźnikowymi” są występujące w formie różnych związków oraz w różnej formie i wielkości: siarczki, fosforki, węgliki, azotki i inkluzje krzemianowe. Zawartość pierwiastków śladowych versus zawartość niklu ujawnia chemiczne klastry (skupienia, clusters) reprezentujące różne chemiczne grupy meteorytów żelaznych. Część meteorytów żelaznych pochodzi z częściowo zdyferencjonowanych planetozymali rozerwanych na początku formowania żelaznego jądra i bogatej w krzemiany skorupy (to grupy IAB i IIE). Pozostałe meteoryty z innych grup pochodzą z jąder małych całkowicie zdyferencjonowanych planetozymali, rozbitych w zderzeniach, krótko po uformowaniu się.
EN
In his catalogue (Klein 1904) Klein described many events concerning meteorites, for example information about a fallen meteorite which destroyed a prison tower in Warsaw in 1600. He managed to find an original source of the information, specify the date and determine which tower had been hit by falling meteorite. The report of that event could be found in one source only and was copied by many searchers. The issue thus remains open whether we deal with a real description of the event.
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The history of finding another Polish meteorite. The process of meteorite preparation for research and classification. Making 3D copies of the specimen and cutting it.
EN
The history, how the Mössbauer studies of meteorites began in Poland, was already described in our “Meteorites Odyssey… 20 years have passed”. One late afternoon (it was probably Spring 1995) I [Jolanta Gałązka-Friedman] was sitting in the Nonna Bakun’s office (at Banacha street) and we were talking about planet Mars. Suddenly Mr. Marian Stępniewski jumped to our room saying: We have a new Polish meteorite. It is called Baszkówka. Do you have any suggestion, how could we study this meteorite? Mössbauer spectroscopy – we both answered at the same time. And this is how it started, and it has been continued for the next quarter of a century. The first results of the Mössbauer studies of the Baszkówka meteorite were presented at the ISIAME conference in Johannesburg in 1996. In this paper we present the most important problems related to meteorites, which were investigated by us using Mössbauer spectroscopy. We will, however, show almost no formulas. We will try to explain everything by a method based on plots of Mössbauer spectra. We will try not to boast too much regarding our successes, but to explain also the problems that we were not able to resolve. While investigating the Baszkówka meteorite, we got most fascinated by troilite. We noticed that most of the laboratories determined the Mössbauer parameters of troilite incorrectly. They did not take into account the so-called theta angle, the value of which depends strongly on the number of vacancies and various additives. We thought that the theta angle may show us the parent body of the investigated meteorite. Unfortunately, this hypothesis turned up to be too difficult to defend. Then we studied Morasko meteorite and we discovered, by the comparison with Baszkówka meteorite Mössbauer spectra, and determined – up to now – not identified mineral phases present also in Morasko, such as pyrrhotite, daubréelite, taenite, tetrataenite, antitaenite and cohenite. In 2019 we published in MAPS a paper titled “Application of Mössbauer spectroscopy, multidimensional discriminant analysis and Mahalanobis distance for classification of equilibrated ordinary chondrites” (4M method), in which a new objective method for classification of ordinary chondrites is based on the knowledge of the Mössbauer spectra of the 4 main mineral phases present in the ordinary chondrites of H, L and LL type. Now we are working on the refinement of the 4M method enlarging our collaborative team by various foreign laboratories.
EN
A description of an ordinary chondrite L6 type fall in Soltmany Village. A report from a fall spot and initial results of examination carried by polish scientists team. An examination of elementary and mineral abundance and magnetic features. History of meteorite fragments.
EN
An anonymous person from Częstochowa in Poland found a new meteorite during the summer of 2008. The specimen was found in eolian sand, where exotic grains connected with glacial activity were not observed. The suspected meteorite was kept in the founder’s possession until the autumn of 2018. This was when the holder of the meteorite contacted the owners of the woreczko.pl webpage, which is dedicated to meteorite identification. Moreover, the webpage was developed and operated by meteorite collectors Jan Woreczko and Wadi. After meeting, Jan and Wadi bought the meteorite, which is now part of their collection. After the meeting, Jan and Wadi bought the meteorite (total meteorite mass 2143 g), which is now part of their collection. Three fragments with their total mass 20.74 g as well as two thin-sections (7.03 g) are deposited at the Earth Sciences Museum, University of Silesia in Katowice. The fusion crust is black to brownish, typical for a chondrite. Regmagliptes are visible. The meteorite is characterized by chondrules, which range in diameter from 0.015 to 1.000 mm in diameter. The most common type of chondrule is represented by olivine (Ol). The barred Ol texture, showing elongate, sub-parallel bars of olivine with clear pyroxenes (Px) and oligoclase between the bars. The second characteristic type is represented by Ol-Px porphyritic chondrules and radial Px chondrules. The matrix is not recrystallized; and the clasts are up to 0.1 to 0.2 mm in diameter. Px and Ol, plagioclase, metallic phases, troilite, and spinel (Cr-spinel) are up to 71.9 vol.%, 11.2 vol.%., 7.0 vol.%., 4.2 vol.%., and 1.1 vol.% of the meteorite, respectively. The average content of the secondary minerals is 4.4 vol.% (close to the outermost part is up to 8–10 vol.%. The meteorite is classified as a H5 ordinary chondrite, based on the Ol and Px composition (Fa/Fs), with an official name ‘Kuźnica’.
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Z efektem Mössbauera na Marsie

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EN
People have been trying to send space vehicles to Mars since the early 1960s to explore the surface of this planet. One of the most important missions in discovering Mars was the Viking mission of 1975, which provided a lot of information shaping knowledge about the red planet at the turn of the century. The idea of sending Mössbauer spectrometer to Mars appeared due to the prevalence of iron in the planet's surfce and due to the specific properties of Mössbauer spectroscopy. Our paper describes the Warsaw project to send a Mössbauer spectrometer (MARMOS) to Mars and the project suggested by scientists from Mainz University (MIMOS II). A special Mössbauer spectrometer was constructed for the MER mission by West European Team. The paper presents the possibilities of using a miniaturized Mössbauer spectrometer for the investigation of archeological artefacts. The Mössbauer spectra obtained on the surface of Mars were discussed. The Mössbauer spectra obtained on the surface of Mars were discussed. The Mössbauer spectra measured on Mars are characterized by three doublets and one or two magnetic sextets. The spectra consist of a Fe3+ doublet (assigned to nanophase ferric oxide), two Fe2+ doublets (assigned to olivine and pyroxen) and two sextets (assigned to nonstoichiometric magnetite) or one sextet (assigned to a hematite-like phase).
EN
In Moessbauer spectrum of Shisr 176 meteorite four main iron-bearing minerals were identified: olivine, pyroxene, kamacite and troilite. Iron distribution among this minerals in Shris meteorite is similar to Sołtmany meteorite and different than in Baszkówka meteorite. As these three meteorites are type L ordinary chondrites this comparison might be used as a basis of a new criterion of the classification of the meteorites.
EN
Mössbauer studies of Chelyabinsk (LL5), Sołtmany (L6) and Grzempy (H5) show that the main iron bearing minerals in these meteorites are: Fe-Ni, troilite, olivine and pyroxene. Based on Mössbauer absorption area of different mineral phases, new set of parameters for classification of the ordinary chondrities were introduced. The most promising parameters are: the ratio of the olivine to pyroxene areas and the ratio of the silicate to metallic areas.
EN
Mössbauer measurements of ordinary chondrites type H performed in room temperature are presented. Three investigated meteorites: Carancas, Juancheng and Gao-Guenie are new falls with different terrestrial history. Results of weathering in different conditions during terrestrial life are well seen in their Mössbauer spectra. The level of weathering determined by scale W is in perfect agreement with Mössbauer measurements of these three ordinary chondrites.
EN
Mössbauer measurements of one sample of the Pułtusk meteorite were performed at room temperature (300 K) and at temperature of liquid nitrogen (80 K). Following mineralogical phases were identified in Mössbauer spectra: olivine, pyroxene, troilite, kamacite, taenite, and a doublet associated with ferric iron. The differences in the percentage of spectral areas obtained for all subspectra are very small. It means that in the range of these temperatures the Debye–Waller factor is the same for all mineralogical phases present in the investigated sample.
EN
Mössbauer spectra of equilibrated ordinary chondrites consist of two sextets due to magnetically ordered iron present in metallic phases and troilite and two doublets due to paramagnetic iron present in olivines and pyroxenes. The Mössbauer spectral areas of the different mineralogical phases in meteorites are proportional to the number of iron ions present in olivines, pyroxenes, metallic phase and troilite. This property of Mössbauer spectra was the basis for constructing various methods for the classification of ordinary chondrites. Review of these methods will be presented.
EN
Mössbauer measurements of three ordinary chondrites type LL were performed at room temperature. Values of spectral areas (SA) connected with troilite were different for investigated meteorites: for Oued el Hadjar – 4.8%, for Bjurböle – 10.6%, for NWA 8590 – 14.9%. Mössbauer spectra were fitted with the use of Recoil program. In all samples values of internal magnetic field and theta angle for subspectrum of troilite were the same: H = 31 T, theta=62°. In the sample of Bjurböle meteorite the signal from pyrrhotite was also noticed (SA = 1.7%, H = 25 T, theta = 33°). For meteorite NWA 8590 two subspectra of pyrrhotite were fitted with following parameters: for pyrrhotite I (SA = 1.1%, H = 27 T, theta= 41°), for pyrrhotite II (SA = 0.7%, H = 22 T, theta = 33°). It is easy to notice that the presence of pyrrhotite is correlated with higher amount of troilite in the samples of ordinary chondrites type LL.
EN
The results of two independent Mössbauer measurements of the same sample of the Pultusk meteorite are discussed. The measurements were performed at room temperature in standard conditions (256 channels) and with higher resolution (1024 channels). Very small differences in the percentage of the spectral areas of all mineralogical phases present in Mössbauer spectrum (olivine, pyroxene, metallic phases, troilite and ferric iron) convince that the measurement performed at standard conditions (256 channels) are sufficient for correct determination of the mineralogical composition of the investigated sample.
EN
Four stony pieces were delivered to our laboratory for checking if they are fragments of meteorites: first sample (sample No. 1) was a fragment of a rock that fell near Leoncin in Poland, second sample (sample No. 2) was a fragment of a rock found also in Poland in the vicinity of Pultusk, third sample (sample No. 3) was a meteorite specimen bought on the meteorite exchange and fourth sample (sample No. 4) was a stone object whose decline was observed in Europe. We obtained mössbauer spectra of the delivered samples. The mössbauer spectrum of sample No. 1 is very similar to the spectrum of ordinary chondrite of type LL. Comparison of the mössbauer spectrum of sample No. 2 with mössbauer spectrum of Pułtusk meteorite showed very large differences. In the spectrum of sample No. 3, a clear signal from iron-nickel alloy and troilite can be observed. These observations indicate that it is an object of extraterrestrial origin. Mössbauer spectrum of Sample No. 4 is similar to the spectrum of terrestrial magmatic rocks. Based on these spectrum we cannot clearly determine where the examined object comes from. This work demonstrates the usefulness of Mössbauer spectroscopy in recognizing samples that are fragments of meteorites.
EN
The 4M method aims to determine the type of equilibrated ordinary chondrite only on the basis of the Mössbauer spectrum of the investigated meteorite. Mössbauer spectrum of non-weathered ordinary chondrite is comprised of four sub-spectra: two doublets and two sextets. One of the doublets consists of a signal from iron present in olivine and the other consists of a signal from iron present in pyroxene. Sextets on the other hand, contain signals from magnetically ordered iron. One sextet is related to the metallic phase (kamacite, taenite), whereas the second is related to troilite. A third of doublets, which emerges in weathered ordinary chondrites, is related to products of the oxidation of iron present in metallic phase. The spectral areas of olivine, pyroxenes, metallic phase and troilite, which were obtained from Mössbauer spectrum are proportional to the number of iron atoms present in relevant mineral phases. Some Mössbauer groups were inspired by this fact to construct different methods to determine the type (H, L, or LL) of investigated meteorites (Gałązka-Friedman et al. 2019, Hyp. Inter. 241(1)). However, these methods, based on subjective criteria, were only qualitative. Our group elaborated a quantitative method, which is based on objective criteria. We called it the "4M method" (where M are derived from meteorites, Mössbauer spectroscopy, multidimensional discriminant analysis (MDA), Mahalanobis distance) (Woźniak et al. 2019). This method was using only the Mössbauer experimental data, to which it applied advanced statistical methods. The base, which was created from Mössbauer data, consisted of three clusters H, L, LL. These clusters were constructed with sets of 4-dimensional vectors. The vectors are comprised of spectral areas of Mössbauer spectrum: ol (value proportional to iron present in olivine), pyr (value proportional to iron present in pyroxene), met (value proportional to iron present in metallic phase), tr (value proportional to iron present in troilite). To determine the type of investigated ordinary chondrite, its ol, pyr, met and tr values with average values of variables obtained for clusters H, L and LL need to be compared. The comparison can be performed with the use of MDA and Mahalanobis distance. Once Mahalanobis distance of the investigated meteoriteis is known, the level of similarity to three types of ordinary chondrites can be calculated. Examples of such calculations were performed for seven ordinary chondrites: Goronyo, Carancas, New Concord, NWA 7733, Leoncin, Sołtmany and Pułtusk. They were made with the use of the new base composed of 62 non-weathered ordinary chondrites. All results obtained with the 4M method yielded results consistent with traditional mineralogical methods.
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EN
Kuźnica meteorite was found in summer 2008 by an inhabitant of Częstochowa in the village of Kuźnica (Poland, voivodeship: Łódź, county: Pajęczano) in Poland. The finder, who is a passionate and collector of interesting stones, shared his find with the world only after a few years in the autumn of 2018. The found meteorite with a mass of 2.14 kg is an ordinary chondrite type H5. The degree of weathering on the surface is W2, inside W1. Currently, the meteorite is represented by 3 parts and two thin plates. The main mass is 2.037 kg, fragments are 13.7 g and 5.81 g. The found object was officially classified as a meteorite on 22th of November 2020. In this paper, we present the results of the Kuźnica meteorite measurements obtained by using the Mössbauer spectroscopy method. Mössbauer measurements of Kuźnica were performed at room temperature. The experimental spectrum was elaborated with “Recoil” program. Nine mineralogical phases were identified in the obtained Mössbauer spectrum: two doublets associated with olivine, two doublets associated with pyroxene, sextet associated with troilite, sextet associated with metallic phase identified as kamacite, doublet associated with iron hydroxides and two sextets associated with oxyhydroxides. The presence of a metallic phase or troilite in the test sample is convincing evidence of its extraterrestrial origin. These are mineralogical phases that can only arise in space conditions. Mössbauer spectroscopy allows for unambiguous identification of these mineralogical phases. In the standard 4M method, we use four basic phases to determine the type of ordinary chondrite: olivine, pyroxene, troilite and metallic phase, and we choose specimens in which the content of weathered phases does not exceed 7%. The Kuźnica meteorite is heavily weathered. The content of weathered phases is as much as 36.4%. Secondary minerals are a breakdown product of the metallic phase and to a lesser extent of the sulphide phase. Due to the strong weathering of the Kuźnica meteorite, we can modify the 4M method using only two basic phases: olivine and pyroxene. The analysis of the location of the Kuźnica meteorite on the figure of pyroxene vs. olivine dependence shows that it is ordinary chondrite type H. In this paper, the influence of the loss of the metallic and sulphide phases on the position of the Kuźnica meteorite on the figure of pyroxene/olivine vs. (pyroxene+metallic phase/(olivine+troilite)) was also checked. Weathering processes significantly transform many minerals. The resulting compounds often have parameters difficult to identify. However, difficulties in identifying secondary phases and their origins should not prevent an attempt to determine the type of meteorites using the 4M method.
EN
Mössbauer 57Fe measurements of three ordinary chondrites type L were performed at room temperature. The measurements were repeated in the same experimental conditions. The experimental spectra were elaborated with „Recoil” program. The absorption areas of the same ordinary chondrite samples were very similar. The maximum variation was about 2% for doublets (paramagnetic iron) and 3% for sextet (magnetically ordered iron).
EN
Mössbauer 57Fe measurements of three ordinary chondrites type H and of three ordinary chondrites type LL were performed at room temperature. The spectral areas were fitted using the “Recoil” program (Lagarec i in. 1998). Fitting was repeated three times which allowed us to determinate the differences between the results of fits performed by different persons.
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