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EN
As a result of the discussion of the wording contained in the latest definitions of a meteoroid and a meteorite and related terms existing in scientific sources, the author slightly modified these definitions. Modifications were made in such a way that the definitions became more unambiguous and universal, and thus could refer to meteorites of any origin on any bodies of any planetary system. Ultimately, these definitions were formulated as follows: Meteoroid: A 10 mm to 1-meter-size solid object of natural origin moving in interplanetary space or coming from space and moving through an atmosphere. Meteoroids maybe primary objects or derived by the fragmentation of larger celestial bodies, not limited to asteroids, but also including moons, planets, etc. Micrometeoroid: A meteoroid between 10 mm and 2 mm in size. Meteorite: A natural solid object larger than 10 mm in size, derived from a celestial body (or being a celestial body itself), that was transported by natural means from the body on which it formed to a region outside the dominant gravitational influence of that body, and that later collided with a natural or artificial body larger than itself (even if it is the same body from which it was launched). Weathering processes do not affect an object’s status as a meteorite as long as something recognizable remains of its original minerals or structure. An object loses its status as a meteorite if it is incorporated into a larger rock that becomes a meteorite itself. Micrometeorite: A meteorite between 10 mm and 2 mm in size. Interplanetary dust particle (IDP): A particle smaller than 10 mm in size moving in interplanetary space or coming from space and moving through an atmosphere. If such particles subsequently accrete to larger natural or artificial bodies, they are still called IDPs. The vaporised material after the meteor phase, that condenses into solid matter is called meteoric smoke. Physical phenomena (light, heat, shock, ionization) resulting from the high-speed entry of a solid object from space into an atmosphere are called a meteor. Meteors can occur on any planet or moon with a sufficiently dense and thick atmosphere. The advantage of defining the terms: meteoroid, meteorite and meteor separately and not linking these definitions to each other is the possibility of a more precise and logical definition of a meteoroid and a much broader, more universal definition of the term meteorite, not limiting it only to terrestrial conditions.
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Chondryt Sołtmany

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EN
The Sołtmany hammer meteorite is classified as an ordinary chondrite type L6, W0, S2. At present it is the most thoroughly and comprehensively examined Polish meteorite. A comprehensive petrological, mineralogical and geochemical analysis alongside the investigation of its physical and particularly thermophysical properties, and, most of all, analyses of cosmogenic radionuclides and noble gases isotopes content, as well as the use of a troilite thermometer has made it possible to draw interesting conclusions concerning the genesis and evolution of the parent body and the history of the parent meteoroid and, finally, the Sołtmany meteorite. The present report attempts at summing up the results of studies conducted at several European research centres in the last four years. The age of the the Sołtmany chondrite parent rock has been defined at 4.137 billion years. It was formed at a temperature of up to 440–450 K (about 170°C), probably at a depth of up to 3 to 7 km under the surface of the parent body, i.e. at a pressure of the order of 1–2.4 kbar. Such a low temperature during the accretion, diagenesis and metamorphism of the parent body may point to its complicated development, which may be in part due to collisions of partially melted planetesimals. Like with other type L ordinary chondrites, one can infer that the parent body could have been destroyed about 467 million years ago, at the time of a catastrophic collision which led to the formation of Gefion family of planetoids. Perhaps one of the bodies in this family was involved in another collision about 29.2 million years ago, which resulted in ejecting the parent meteoroid of the Sołtmany chondrite onto the Earth collision trajectory. Before entering the Earth’s atmosphere, this meteoroid had the mass of about 36 kg and the diameter of ca 13.5 cm. During its flight through the atmosphere, it rotated and somersaulted, which resulted in the formation of an uniform thin (0.5–0.7 mm) fusion crust, whose temperature reached 1000°C. In the last phase, the Sołtmany meteorite fell almost vertically and its mass was a mere 3% of the mass of the parent meteoroid – 1.066 kg. It hit the roof and then the concrete stairs of a farm building, which caused it to break into two bigger and many small pieces. It was found a few minutes after the fall, which occurred at 6:03 a.m. (CEST, UTC+2:00) on 30 April 2011, by Wydmińskie Lake in northern Poland (54°00,53’N, 22°00,30’E). The Sołtmany chondrite is one of just 14 meteorites in which the activity concentration of the cosmogenic 52Mn has been determined, and one of the few ordinary chondrites where the concentration of organic matter has been defined. As a result, it was found out that unlike in carbonaceous CI chondrites, the composition of organic particles is dominated by less complex compounds (CHO and CHOS) than CHNO and CHNOS compounds. This may indicate the decomposition of more complex organic compounds into particles with simple structures during magmatic and metamorphic processes related to formation of type L ordinary chondrites.
EN
In this article the authors present a simple method of determining the content of selected metal raw materials (Fe, Ni, Co) on the parent bodies of ordinary chondrites. Thanks to the use of planimeter for measuring, under microscope, polished slices of meteorites, it is possible to estimate quite accurately the proportion of these metals in the parent bodies of meteorites, i.e. on asteroids. When it comes to analysing a large number of polished slices, these results will be most likely comparable to much more expensive results of chemical tests conducted on meteorites. Based on the analysis of 16 thin polished sections and polished slices of 11 ordinary chondrites, the authors found out that the highest content of Fe, Ni and Co ore minerals, reaching 10,06% of the total volume, can be found in ordinary chondrites from group H. For ordinary chondrites from groups L and LL, it makes 3,86% and 3,93% of the volume respectively. Employing the results of chemical analyses available in literature sources, the authors also estimated the size of Fe, Ni and Co resources for several selected asteroids. These bodies contain higher concentrations of iron, nickel and cobalt than terrestrial deposits (those found in the earth’s crust). The total content of Fe on parent bodies of even the most deficient in metals group LL of ordinary chondrites is about twice as high as that in the earth’s crust. Cobalt occurs on parent asteroids of ordinary chondrites in concentrations 15–24 times as high as those in the earth’s crust, and the concentrations of Ni are 100–180 times as high as those in the earth’s crust. The contents of these metals on parent asteroids of ordinary chondrites are also several times as high as those in currently extracted deposits in the earth’s crust. Taking into account the mean annual terrestrial production of these metals, the authors have estimated that a parent asteroid of ordinary chondrites with the size between 433 Eros and 6 Hebe could satisfy our need for Fe, Ni and Co for the nearest several million to dozens of billion years. Considering the fact that asteroid belt contains plenty of such objects, and as many asteroids built chiefly of Fe-Ni alloy, one should regard this section of the Solar System as a practically inexhaustible source of metal raw materials. The prospect of their exploitation is probably much nearer than we can currently imagine.
EN
Based on petrological, mineralogical and geochemical research authors classified new meteorite Northwest Africa 11779 as the ordinary chondrite L6, S1, W1. Chemical composition of olivine crystals (Fa 24.9 mol.%) and of pyroxene crystals (Fs 19.4 mol.%) proved that this meteorite belongs to L chondrites. However, bulk chemical composition of NWA 11779 is not typical for L chondrites. Nevertheless, all analyzed elements (except Mo, Sn and Nb) are in abundances reported for L chondrites, some of elements have concentration closed to average abundances for L chondrites. The content of chosen, characteristic lithophile, siderophile and chalkophile elements in NWA 11779 chondrite is in most cases in accord with its typical abundance in L chondrites. Presence of poorly defined chondrules, secondary feldspar crystals larger than 50 µm in size, absence of glass within chondrules, coarse recrystallized matrix (with olivine crystals of 0.5 mm in diameter and pyroxene crystals of 0.3 mm in diameter) as well as carbon content below 0.2 wt% proved that studied meteorite belongs to the petrologic type 6. The only difference from characteristic features of petrologic type 6 in case of NWA 11779 chondrite is presence of ca. 10% of monoclinic Ca-poor pyroxenes. Undulatory extinction by olivine and absence of other shock features in this chondrite allow to determine the shock level as S1. Weathering grade of NWA 11779 was identified as W1 based on weathering of only FeNi alloy grains. The outer part of metallic grains as well as contact zones of FeNi and FeS are changed due to weathering. Between 10 and 20% of FeNi alloy grains are oxidized to iron oxides and hydroxides. These secondary products of weathering replace outer zone of FeNi grains and fill the small cracks, creating a few thin veins.
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Nowy chondryt z Libii

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EN
On Saturday, 21 of May, 2006, a fall was observed and the stony meteorite was found in a small crater on an apple farm at Werdama village, near Al Beda town in Libya. Based on preliminary examinations, the authors described the meteorite as an ordinary chondrite. Further research aiming at full characteristics, classification and registration of the meteorite is in progress.
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EN
The authors drew attention to the classification in December 2022 of over one ton of lunar meteorites that fell to Earth. They have been found since the early 1960s, but their first classification, as lunar meteorites, was made only in 1982. This was possible thanks to more advanced geochemical research and the possibility of comparing their results with the results of analyzes of samples of rocks and lunar regolith brought by the Soviet missions of the Luna program, and above all by several American missions of the Apollo program. With access to over 1.4 tons of lunar rocks on Earth, we are now able to conduct multidisciplinary studies of the lunar geology. Their results are particularly important in the context of building human settlements or lunar bases for further exploration of the solar system. This applies to both the physical properties of these rocks, as well as their chemical and mineral composition in the context of the presence of deposits of various mineral resources. It should be emphasized that meteoritic material from the Moon has been increasing in terrestrial collections (especially scientific ones) very quickly since 2015. This is the result of extensive exploration work, primarily in Antarctica, Africa, the Arabian Peninsula and Australia. Among the identified rocks reaching the Earth in the form of lunar meteorites, the most numerous are feldspar breccias (impact metamorphic rocks), anorthosites (plutonic igneous rocks building highlands areas of the silver globe) and basalts (extrusive igneous rocks building areas of the lunar maria). In addition, there are other igneous mafic rocks, such as gabbro, norite, troctolite and others. The surface of the crust is covered with regolith composed of fragments of the above-mentioned igneous rocks and breccias subjected to fragmentation by successive collisions with meteorites and micrometeorites and the action of solar wind particles (space weathering). As a result of these processes, the surface of the Moon is covered with a layer of loose sedimentary rock with a thickness of a few to several meters. Locally, a regolith may be a compact clastic sedimentary rock if a significant number of rock fragments are welded together with the glaze produced during collisions with micrometeorites. The authors also briefly presented the genesis and evolution as well as the geological structure of the Moon based on the results of the latest geophysical and geochemical (including isotopic) as well as mineralogical and petrological research. They pointed out that the proposed model of the genesis of the Moon from synestia formed after the collision of the proto-Earth with another hypothetical planetary embryo called Theia, explains well the chemical and isotopic homogeneity of the Earth and the Moon. The authors also pointed out that due to the common genesis, lunar meteorites are classified and named in the same way as terrestrial rocks, which definitely distinguishes them from other meteorites. The exceptions are Martian and HED meteorites, which are classified similarly to terrestrial rocks, although their names often do not have equivalents in the classification of terrestrial rocks (e.g. SNC meteorites). Tracking data on officially classified lunar meteorites, the authors found that in December 2022, the total mass of meteoritic matter considered to coming from the Moon exceeded 1 ton. Lunar meteorites are currently the largest source of information about the geology of the Silver Globe, accounting for almost two-thirds of the mass of lunar material available for study on Earth.
PL
Autorzy zwrócili uwagę na sklasyfikowanie w grudniu 2022 roku już ponad tony meteorytów księżycowych, jakie spadły na Ziemię. Znajdowane były one od początku lat sześćdziesiątych XX wieku, jednak pierwsze ich klasyfikacje jako meteorytów księżycowych wykonane zostały dopiero w 1982 roku. Możliwe to było dzięki bardziej zaawansowanym badaniom geochemicznym i możliwości odniesienia ich wyników do wyników analiz prób skał i regolitu księżycowego przywiezionych przez misje radzieckie programu Łuna, a przede wszystkim przez kilka misji amerykańskich programu Apollo. Dzięki dostępowi na Ziemi do ponad 1,4 tony skał księżycowych możemy obecnie prowadzić multidyscyplinarne badania geologii Księżyca. Ich wyniki są szczególnie ważne w kontekście budowy osiedli ludzkich lub baz na Księżycu w celu dalszej eksploracji Układu Słonecznego. Dotyczy to zarówno właściwości fizycznych tych skał, a także ich składu chemicznego i mineralnego w kontekście występowania złóż różnorodnych surowców mineralnych. Należy podkreślić, że materiału meteorytowego z Księżyca przybywa w ziemskich kolekcjach (zwłaszcza naukowych) bardzo szybko dopiero od roku 2015. Jest to efektem szeroko zakrojonych prac poszukiwawczych przede wszystkim na obszarze Antarktydy, Afryki, Półwyspu Arabskiego i Australii. Wśród zidentyfikowanych skał docierających na Ziemię w postaci meteorytów księżycowych najliczniej reprezentowane są brekcje skaleniowe (impaktowe skały metamorficzne), anortozyty (skały magmowe głębinowe budujące wyżynne obszary Srebrnego Globu) oraz bazalty (skały magmowe wylewne budujące obszary mórz księżycowych). Poza tym spotykane są inne skały magmowe zasadowe, takie jak gabro, noryt, troktolit i inne. Powierzchnię skorupy pokrywa regolit złożony z fragmentów wymienionych skał magmowych i brekcji poddanych rozdrabnianiu kolejnymi zderzeniami z meteorytami i mikrometeorytami oraz działaniu cząstek wiatru słonecznego (wietrzenie kosmiczne). W wyniku tych procesów powierzchnia Księżyca pokryta jest warstwą luźnej skały osadowej okruchowej o miąższości od kilku do kilkunastu metrów. Lokalnie regolit może być skałą osadową okruchową zwięzłą, jeśli znaczna liczba okruchów skalnych ulegnie połączeniu (zespawaniu – ang. welding) szkliwem produkowanym w czasie zderzeń z mikrometeorytami. Autorzy przedstawili także krótko genezę i ewolucję oraz budowę geologiczną Księżyca w oparciu o wyniki najnowszych badań geofizycznych i geochemicznych (w tym izotopowych) oraz mineralogicznych i petrologicznych. Wskazali, że zaproponowany model genezy Księżyca z synestii utworzonej po zderzeniu proto-Ziemi z innym hipotetycznym embrionem planetarnym o nazwie Theia, dobrze tłumaczy jednorodność chemiczną i izotopową Ziemi i Księżyca. Autorzy zwrócili także uwagę, że dzięki wspólnej genezie meteoryty księżycowe klasyfikowane i nazywane są tak samo, jak skały ziemskie, co zdecydowanie odróżnia je od innych meteorytów. Wyjątek stanowią meteoryty marsjańskie oraz HED, które klasyfikowane są podobnie, jak skały ziemskie, aczkolwiek ich nazwy często nie mają odpowiedników w klasyfikacji skał ziemskich (np. meteoryty SNC). Śledząc dane na temat oficjalnie klasyfikowanych meteorytów księżycowych autorzy stwierdzili, że w grudniu 2022 roku łączna masa materii meteorytowej uznanej za pochodzącą z Księżyca przekroczyła 1 tonę. Meteoryty księżycowe są obecnie największym źródłem informacji o geologii Srebrnego Globu, stanowiąc niemal 2/3 masy materii księżycowej dostępnej do badań na Ziemi.
EN
Wlotzka scale (Wlotzka 1993) is commonly used to determine the weathering grade of ordinary chondrites. The scale is descriptive and based mostly on a subjective assessment of researcher. In this paper authors define a new, quantitative method to establish the W0–W4 weathering grade, which is based on planimetry of FeNi grains. Results of planimetry are compared with average content of FeNi metal in unweathered chondrites from the same group. Weathering grade estimated by this method are consistent with, or slightly different from the official one determined in classification, what proves the efficacy of the proposed method. Moreover, the method was applied to define weathering grade of meteoritic samples not classified so far: Pułtusk (W2), Thuathe (W2), Gao-Guenie (W2/W3), NWA 5205 (W3), NWA 4505 (W3), NWA 5296 (W2).
EN
The chemical composition of carbonaceous chondrites was analysed in terms of the content of selected 24 metals, including noble metals and rare-earth metals. Based on the obtained results, the abundance of C-type asteroids in metallic raw materials was estimated and compared to the concentration of terrestrial deposits and the average content in the Earth’s crust. All the analysed elements, except rare earths, showed higher concentrations in carbonaceous chondrites than in the Earth’s crust, but most of them did not match the Earth’s deposit contents. The exception is Fe and Ni, the concentrations of which in carbonaceous chondrites significantly exceed the Earth’s deposit concentrations. The profitability of mining operations on C-type asteroids is also increased by the number of accompanying mineral commodities, mainly metals (Cr, Co, Cu, Au, Pt, Pd, Ag), and water ice. In addition, the parent bodies of carbonaceous chondrites occur relatively close to the moons of Jupiter and Saturn – potential space mission targets.
EN
Some of M type asteroids, like 016 Psyche, 022 Kalliope, 055 Pandora, 110 Lydia, 250 Bettina, 347 Pariana, 678 Fredegundis, 771 Libera, 872 Holda, are probably the source of iron meteorites. The population of these asteroids is less than 10% of all minor bodies orbiting the Sun in the asteroid belt. In the paper we analyzed the concentrations of 19 selected metals in 1730 iron meteorites according to the groups. Base on it authors found out that beside Fe and Ni the parent bodies of iron meteorites are the richest in Co, Cu, Ge, Cr, and Ga. They are also rich in As, Pt, Mo, Os, Pd, and Ir. The iron meteorites of IVB group are the richest in metals. Meteorites belonging to this group contain the highest average concentrations of Ir, Co, W, Re, Pt, Os, Pd, Rh, Ru, Mo, and Ni. Meteorites from IAB group are the richest in Ge, As, Sb and Au. The parent bodies of iron meteorites, especially from IVB and IAB groups, can be recognized as very rich polymetallic deposits. The concentrations of most of 19 analyzed metals in iron meteorites are greater than the concentrations in Earth’s crust. Only tungsten and chromium according to their strong litophile character occur in lower concentrations than in Earth’s crust. Few of the M type asteroids, those that are the source of iron meteorites, are probably the most differentiated bodies in the asteroid belt. Their chemical composition considerably differs from the composition of CI carbonaceous chondrites. Among their the most differentiated (enriched in some elements and depleted in others) and differing from CI chondrites are the parent bodies of iron meteorites belonging to IVB group. However even they are far less differentiated than Earth’s crust. This is the proof of relatively long chemical evolution of IVB group parent body comparing to parent bodies of other groups of iron meteorites and CI chondrites, but from the other hand the evolution of this body is also significantly shorter than the chemical evolution of Earth’s crust.
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