The chemical compositions of Antarctic iron meteorites and their classification

The concentrations of 13 elements in the metal of 52 Antarctic irons have been reported and these irons have been classified based on the structures and their Ga,Ge, Ni, Ir and other trace elemental contents. The 52 iron meteorites assigned to chemical group consist of 16 of ⅠAB,12 of ⅡAB, 1 of ⅡE,3 of ⅢAB, 1 of ⅢCD, 1Of ⅣA and 18 of ungrouped irons. The ⅠAB, ⅢCD and ⅡE iron meteorite groups areconsidered to be of nonmagmatic origin. Nonmagmatic ⅠAB, ⅢCD and ⅡE ironsformed as individual pools of a chondritic body. The other groups, ⅡAB, ⅢAB andⅣA show the evidences of having originated by fractional crystallization of a metallicmagma.The slopes on element-Ni trends in the magmatic are generally higher than inthe nonmagmatic groups. Most interestings are the high abundance Of ungrouped andⅠAB (47.2% and 27.8%,respectively) and low abundance of ⅢAB (5.8%).Antarctic irons of the group abundances can be distinguished from non-Antarctic irons,which provide the information about previously unsampled parent planets, mass,shockand collision,as well as nebula regions.

Progress in study of Chinese Antarctic Meteorites

This paper reviews and summarizes the Chinese Antarctica meteorite search, classification and research. During the past four antarctic explorations, a total of 9834 meteorites were collected in the Grove Mountains region. Among them, 2431 meteorites were classified by the end of 2008. So far, 684 meteorites have been officially published in the Meteoritical Bulletin, Meteoritical Society, including 2 martian meteorites, 2 eucrites, 6 ureilites, 5 mesosiderites, 1 pallasite, 1 iron and 10 carbonaceous chondrites. Comprehensive studies were carried out on a number of these rare type meteorites. In addition, we propose to continue the meteorite searching project in Grove Mountains and other regions in Antarctica. We also suggest several key topics of the future researches on the Chinese Antarctic meteorites.

Meteorite classification for building the Chinese Antarctic Meteorite Depository Introduction of the classification of 500 Grove Mountains meteorites

Meteorites provide an important window into the origins and evolution of the solar system. Since the first four meteorites were recovered in Grove Mountains, Antarctica, in 1998, a further total of 12665 meteorites have been collected over seven polar seasons in the Grove Mountains. All of these meteorites are owned and managed by the Chinese Antarctic Meteorite Depository （CAMD） at the Polar Research Institute of China （PRIC）. In recent years, another 500 Antarctic meteorites have been classified and characterized based on mineralogy and petrology. In this work we examine four samples that have been identified as terrestrial, and a further 496 samples that have been confirmed as meteorites. These meteorites are further divided into different types：488 ordinary chondrites, one eucrite, one ureilite, one CM2 carbonaceous chondrite, one EH4 enstatite chondrite, one mesosiderite and three iron meteorites. The classification of meteorites not only provides an abundance of fundamental scientific data, but is also significant for introducing meteorites and related scientific knowledge to the publics particularly via the website of Chinese Resource-sharing Platform of Polar Samples for scientific research and education.

Siderophile Element Compositions of Pyroxenes in HED Meteorites: Implications for the Differentiation of Magma Ocean on Vesta

1 Introduction The howardite,eucrite and diogenite(HED)meteorites are ultramafic and mafic igneous rocks and impact-engendered breccias derived from a thoroughly differentiated asteroid 4 Vesta.Diogenites include dunites,

Lunar meteorites: witnesses of the composition and evolution of the Moon

Lunar meteorites are fragments of the Moon that escaped the gravity of the Moon following high-energy impacts by asteroids, subsequently fell to Earth. An inventory of 165 lunar meteorites has been developed since the discovery and identification of the first lunar meteorite, ALHA 81005, in 1979. Although the Apollo samples are much heavier in mass than lunar meteorites, the meteorites are still an important sample supplement for scientific research on the composition and history of the Moon. Apart from a small amount of unbrecciated crystalline rocks, the majority of lunar meteorites are breccias that can be classified into three groups： highland feldspathic breccia, mare basaltic breccia, and mingled（including fledspathic and basaltic clasts） breccia. The petrography of lunar rocks suggests that there are a series of rock types of anorthosite, basalt, gabbro, troctolite, norite and KREEP in the Moon. Although KREEP is rare in lunar rocks, KREEP components have been found in the increasing number of lunar meteorites. KREEP provides important information on lunar magmatic evolution, e.g., the VHK KREEP clasts in SaU 169 may represent the pristine lunar magma （urKREEP）. Six launching pairs of lunar meteorites have been proposed now, along with ten possible lunar launching sites. In addition, symplectite is often found in lunar basalts, which is a significant record of shock metamorphism on the lunar surface. Furthermore, isotopic ages and noble gases not only provide information on crystallization processes in lunar rocks and the formation of lunar crust, but also provide insight into shock events on the lunar surface.

Classification of Grove Mountains meteorites and its significance

Meteorites are the extraterrestrial rocks, which provide insights into the origin and evolution of the solar system. During the past half century, a great number of meteorites has been discovered on the Antarctic Ice Sheet, confirming that the Antarctica is the most important meteorite concentration area on the earth. Since the first four Antarctic meteorites were found in Grove Mountains in 1998, a total of 9834 meteorites have been collected by four subsequent expeditions. It opens a new field of meteorite study in China, and also accumulates a great deal of scientific samples for China. Recently, classification of Grove Mountains meteorites has been carried out for 6 years, and made following progresses ： （ 1 ） 2433 meteorites, which include many special meteorites, e.g. Martian meteorites, ureilites and carbonaceous chondrites, have been classified. （2） the Antarctic meteorite curation and the sample sharing system are set up preliminarily. （3） the classification procedure, the management of meteorite samples, and the application procedure for the Antarctic meteorites are completed after the systematic classification during these years. （4） young generation researchers on meteorite are trained through the cooperation of many universities and institutes on meteorite classification.

MOSSBAUER SPECTROSCOPIC STUDY OF FIRED SHENQIU METEORITES

The Shenqiu meteorite was investigated by Mossbauer spectroscopy at room temperature, atomic absorption, X-ray diffraction and scanning electron microscopy. In order to determine fired conditions of the meteorite which occurred during the meteorite fall, Shenqiu meteorite samples were fired in an oxidizing atmosphere and a reducing atmosphere at temperatures up to 1300℃, respectively. These samples also were fired at 800, 1000 and 1200 ℃ respectively for different time (up to 24 h).

SEARCH FOR FOSSIL TRACKS FORMED BY COSMIC NUCLEARITES IN METEORITES

Based on the proposal by Witten,De Rujula and Glashow,we carried out the experimental search on two meteorites for the fossil tracks formed by cosmic nuclearites with masses ranging from M~6×10^(-4)g up to very large mass.An upper limit 2km-2y-1(2πsr)-1 was obtained for the cosmic nuclearites with masses larger than 6×10^(-4)g which passed through these meteorites.

The digital mapping of satellite images under no ground control and the distribution of landform, blue ice and meteorites in the Grove Mountains, Antarctica

The colorful satellite image maps with the scale of 1∶100000 were made by processing the parameters-on-satellite under the condition of no data of field surveying. The purpose is to ensure the smooth performance of the choice of expedition route, navigation and research task before the Chinese National Antarctic Research Expedition (CHINARE) first made researches on the Grove Mountains. Moreover, on the basis of the visual interpretation of the satellite image, we preliminarily analyze and discuss the relief and landform, blue ice and meteorite distribution characteristics in the Grove Mountains.

Arab metallurgy owes much to meteorites iron—A special regard to Damask saber

Ancient Arabs have recognized metallic and mineral ores, including their fluid inclusions which were still considered as a new scientific fields in the 70’s last century. They discovered metallic ores (gold, silver, copper), in inhabited areas and in delta and river crosses, using different techniques for exploration and exploitation. Metallic industry flourished during the Islamic period, silver and gold were used as currency for commercial exchanges. Meteorites were also recognized by Ancient Arabs. They collected them in the deserted areas, and used them for arms manufacturing, as sabers and daggers. The more famous of these arms is the Damask saber steel, known reputedly Jaohar. It has an extraordinary mechanical properties, and exceptional sharp cutting edge. The Jaohar blades were forged directly from fall meteorites, at temperature of 80℃, using a sophistical thermomechanical of forging, annealing to refine the steel, and giving it this exceptional quality and superelastic behavior. Meteorites using by Ancient Arabs come back to 400 years ago, as confirmed by a recent research on two meteorites samples, presented in Aleppo museum, found in Ras Shamra, and Umm El Maraa, in Syria.

Quantum Meteorites: An Extemporaneous Description of the System of the World

We extemporaneously summarize the theoretical scheme we have introduced recently in this note to account for the (hidden) functioning of the System of the World at the quantum level. We further explore the relevance, the pertinence and the potential validity of this scheme. We obtain new fundamental results, bearing notably on the nature and the origin of the “virtual particles” conventionally called upon in quantum field theories to explain the Casimir Effect. We define the concept of quantum meteorites in this context. We disable the Heisenberg Uncertainty Principle, judged to be a (mis) interpretation of otherwise legitimate observations, and we replace it with our new XQP Absolute Certainty Principle.

A Study on the Recovery and Classification of Meteorites from the Mt. Grove Region of Antarctica

The Antarctic Continent has become the largest natural preservatory of meteorites in the world because of its unique geographical position and climatic conditions. Mt. Grove is located in the inland area of the Antarctic Continent where the conditions are favorable for the preservation of meteorites. During China's 15th, 16th and 19th Antarctic Scientific Explorations a large number of meteorites were recovered in the Mt. Grove region. Especially during the 19th Exploration in 2002/03 a total of 4448 meteorites were recovered, which at one stroke put China among countries that have recovered most numbers of meteorites. Here, we report mainly the results of microscope and electron microprobe studies of 28 meteorites recovered during the 16th Exploration. The meteorites are chemically classified based on their mean Fa contents of olivine, mean Fs contents of low-Ca pyroxene and abundances of Fe-Ni metal. We also give a brief account of the meteorite recovery during the three Explorations and of some preliminary classification results of the Antarctic meteorites.

Chemical compositions and cassfication of Grove Mountains(GRV)98003 and other Chinese iron meteorites

Concentrations of Cr, Co, Ni, Cu, Ga, Ge, As, Sb, W, Re, Ir, Pt and Au of two ungrouped iron meteorites, Grove Mountains （GRV） 98003 from Antarctica and Ujimqin, were measured using instrumental neutron activation analysis. According to the bulk chemistry, GRV 98003 is classified as a member of ⅠAB group, and Ujimqin as a unique one of ⅠAB iron meteorite complex. The elemental abundance pattern and correlation between elements （e. g. Ni-Au, Co-Au, As-Au, W- Au, Cu-Au, Sb-Au） of GRV 98003 are similar with those of NAW 468 （ⅠAB）, but significantly depleted in refractory siderophile elements （ Re, It） and moderate volatile elements （Ca, Ge） relative to the latter. In addition, we reclassify Nantan （ⅢCD） as a member of ⅠAB main group （MG） and Yongning （ⅠA） as a unique iron meteorite related with IAB iron meteorite complex.

Challenges of identifying putative planetary-origin meteorites of non-igneous material

This paper summarizes the challenges of identifying planetary-origin meteorites of non-igneous composition - particularly those of sedimentary origin.Evidence for putative sedimentary-origin (sedtype) meteorites and their potential parent bodies is reviewed,suggesting that the list of candidate parent bodies for sed-type meteorites includes,but is not limited to,Mars,Enceladus,Ganymede,Europa,Ceres,Vesta,and other hypothetical planets that existed between the orbits of Mars and Jupiter in the past.The extraterrestrial origin and probable parent body for sed-type meteorites should be assessed based on multiple lines of evidence,and not solely limited to tests of oxygen and noble gas isotopes,whose signatures may undergo terrestrial contamination and which may exhibit significant heterogeneity within both the Solar System and parent cosmic bodies.The observed fall of a cosmic body,evidence of hypervelocity fall,signs of impact,presence of fusion crust,melting,and/or shock deformation features in impactor fragments should be considered as priority signs of meteoritic origin.

Meteorites from Grove Mountains, Antarctica:An overview

Thirty-two meteorites were collected in Grove Mountains area, Antarctica, by the 15th and 16th Chinese Antarctic Research Expeditions (CHINARE). Petrography and mineral chemistry of these meteorites are reviewed, among which there are one Martian lherzolite, one eucrite, one ungrouped iron meteorite, and six unequili-brated and twenty-three equilibrated ordinary chondrites. An equilibrated ordinary chondrite GRV 98004 ( H5 ) has an unusually low cosmic-ray exposure age. Meteorite concentrating processes in Grove Mountains area are discussed. In addition, future studies on Grove Mountains (GRV) meteorites are proposed.

Shock metamorphism in meteorites

Shock metamorphism resulting from hyperveloeity collisions between planetary bodies, is a fundamental processes in the solar system. The term ＂shock metamorphism＂ is used to describe all changes in rocks and minerals resulting from the passage of shock waves. Most meteorites have experienced coUisions and have a record of shock metamorphism, which includes brecciation, deformation, phase transformation, local melting and crystallization. The key to reading this record is to use the shock features to estimate the pressure and duration of shock event. In this paper, the history of the study of shock metamorphism is reviewed; basic knowledge of shock physics is discussed; recent 10 years＇ studies of shock-induced melt veins are summarized; and finally a short note to the shock metamorphism in general is given.

Alpha Centauri System and Meteorites Origin

We propose a mathematical model for determining the probability of meteorite origin, impacting the earth. Our method is based on axioms similar to both the complex networks and emergent gravity. As a consequence, we are able to derive a link between complex networks and Newton’s gravity law, and as a possible application of our model we discuss several aspects of the Bacubirito meteorite. In particular, we analyze the possibility that the origin of this meteorite may be alpha Centauri system. Moreover, we find that in order for the Bacubirito meteorite to come from alpha Cen and be injected into our Solar System, its velocity must be reduced one order of magnitude of its ejected scape velocity from alpha Cen. There are several ways how this could happened, for example through collision with the Oort cloud objects (located outside the boundary of our Solar System), and/or through collisions within the Solar meteorites belt (located between Mars and Jupiter). We also argue that it may be interesting to study the Bacubirito meteorite from the perspective of the recently discovered Oumuamua object.

Meteorites Penetration into the Dense Layers of the Earth＇s Atmosphere： Physical Mechanism behind the Explosive Phenomena

This discussion paper is an attempt to consider new ideas about the nature of explosive phenomena of the meteorite bodies in the Earth＇s atmosphere. Authors attract approaches, based on the concepts of physics of combustion, explosion and detonation in order to explain the explosive collapse of the meteorite. Authors believe that the meteorite explosion may be the result of gas-detonation mechanism of overheated meteoric bodies explosive boiling-up （the ＂vapor explosion＂）, accompanied by the formation of a supersonic front of shock wave. The considered hypothesis regarding the role of the ＂vapor explosion＂ in geological disasters can be used to explain the mechanisms of explosive phenomena in Volcanology： （1） With respect to the description of nature of phreatic eruptions; （2） for interpretation of dynamic regularities of the volcano crater opening and the subsequent shock-wave emission of steam-gas ＂fountain＂ to a height of several kilometers with fragments of magma and rocks as a result of the ＂vapor explosion＂ of overheated magma mass under the dome of the volcano.

Mineralogy of Meteorites from the North-Eastern India: A Brief Review

We present a brief overview of meteorites from the north-eastern India, with a focus on falls, finds, and research developments. To date, out of a total 150 numbers of meteorites fall/find in India (in Meteoritical Bulletin Database), only six meteorites from north-eastern region have received official international recognition from the Nomenclature Committee of the Meteoritical Society. Among these six meteorites, 2 finds and 4 falls, including one ureilite, two H chondrites and three L chondrites. The first meteorite from north-eastern India (Assam L5, Find) was documented in 1846. After a lack of 153 years, the first fall (Sabrum LL6 chondrite) was documented in 1999. The most recent fall is Kamargaon (L6) chondrite in 2015. Intensively researched meteorites of this region are Goalpara and Dergaon. The reported most massive meteorite of north-eastern India is Mahadevpur (H4/5) chondrite, 70.5 kg of total known weight, and the rest are <13 kg of total known weight. The researches on these meteorites from north-east India can be applied to the newly recovered meteorites to understand the astrophysical enigma.

Micromechanical testing and property upscaling of planetary rocks:A critical review

Knowledge of the mechanical behavior of planetary rocks is indispensable for space explorations.The scarcity of pristine samples and the irregular shapes of planetary meteorites make it difficult to obtain representative samples for conventional macroscale rock mechanics experiments(macro-RMEs).This critical review discusses recent advances in microscale RMEs(micro-RMEs)techniques and the upscaling methods for extracting mechanical parameters.Methods of mineralogical and microstructural analyses,along with non-destructive mechanical techniques,have provided new opportunities for studying planetary rocks with unprecedented precision and capabilities.First,we summarize several mainstream methods for obtaining the mineralogy and microstructure of planetary rocks.Then,nondestructive micromechanical testing methods,nanoindentation and atomic force microscopy(AFM),are detailed reviewed,illustrating the principles,advantages,influencing factors,and available testing results from literature.Subsequently,several feasible upscaling methods that bridge the micro-measurements of meteorite pieces to the strength of the intact body are introduced.Finally,the potential applications of planetary rock mechanics research to guiding the design and execution of space missions are environed,ranging from sample return missions and planetary defense to extraterrestrial construction.These discussions are expected to broaden the understanding of the microscale mechanical properties of planetary rocks and their significant role in deep space exploration.