Добірка наукової літератури з теми "Extraterrestrial material analyses"

AbstractThe composition of interstellar matter is driven by environmental parameters and results from extreme interstellar medium physico-chemical conditions. Astrochemists must rely on remote observations to monitor and analyze the interstellar solids composition. They bring additional information from the study of analogues produced in the laboratory, placed in simulated space environments. Planetologists and cosmochemists access and spectroscopically examine collected extraterrestrial material in the laboratory. Diffuse interstellar medium and molecular clouds observations set constraints on the composition of organic solids that can then be compared with collected extraterrestrial materials analyses, to shed light on their possible links.

Mineralogical and chemical investigations were carried out on intra-craterial bedrocks (Lower Devonian sandstone) and regolithic residual soil deposits present around the Amguid structure, to discuss the hypothesis of its formation through a relatively recent (about 0.1 Ma) impact event. Observations with an optical microscope on intra-craterial rocks do not unequivocally confirm the presence of impact correlated microscopic planar deformation features (PDFs) in quartz crystals. Field observations, and optical and instrumental analysis (Raman spectroscopy) on rocks and soils (including different granulometric fractions) do not provide any incontrovertible pieces of evidence of high energy impact effects or products of impact (e.g., high pressure—temperature phases, partially or totally melted materials, etc.) either in target rocks or in soils. A series of selected main and trace elements (Al, Fe, Mg, Ni, Co and Cu) were analysed on rocks and soils to evaluate the presence in these materials of extraterrestrial sources. Comparative chemical data on rocks and soils suggest that these last are significantly enriched in Fe-poor Mg-rich materials, and in Co, Ni and Cu, in the order. A large number of EDAX-SEM analyses on separated soil magnetic particles indicate an abnormally high presence of Al-free Mg-rich sub-spherical or drop-like silicate particles, showing very similar bulk chemistries compatible with forsterite olivine. Some particles were found associated with a Ni-rich iron metal phase, and this association suggests a specific extraterrestrial origin for them. Electron microscope analysis made on a large number of soil magnetic particles indicates that 98% of them are terrestrial phases (almandine garnet, tourmaline and Fe-oxides, in abundance order), whereas, only a few grains are of questionable origin. One of the Mg-rich silicate particles was found to be a forsterite (Mg = 0.86) Mn-rich (MnO: 0.23%) Cr-free olivine, almost surely of extraterrestrial sources. Electron microprobe analysis of three soil particles allowed identification of uncommon Cr-rich (Cr2O3 about 8%) spinels, poorly compatible with an origin from terrestrial sources, and in particular from local source rocks. We propose a specific extraterrestrial origin for sub-spherical olivine particles characterised by quite similar magnesian character. Excluding any derivation of these particles from interplanetary dust, two other possible extraterrestrial sources should be considered for them, i.e., either normal micrometeorite fluxes or strongly un-equilibrated, or the Vigarano type Carbonaceous (CV) chondrite meteorite material. In this case, further studies will confirm an impact origin for Amguid, as such magnesian olivine components found in soils might represent the only remnants of a vaporised projectile of ordinary non-equilibrated meteoritic composition.

Context. Because comets are part of the most primitive bodies of our solar system, establishing their chemical composition and comparing them to other astrophysical bodies gives new constraints on the formation and evolution of organic matter throughout the solar system. For two years, the time-of-flight secondary ion mass spectrometer COmetary Secondary Ion Mass Analyzer (COSIMA) on board the Rosetta orbiter performed in situ analyses of the dust particles ejected from comet 67P/Churyumov-Gerasimenko (67P). Aims. The aim is to determine the H/C elemental ratio of the refractory organic component contained in cometary particles of 67P. Methods. We analyzed terrestrial and extraterrestrial calibration samples using the COSIMA ground-reference model. Exploiting these calibration samples, we provide calibration lines in both positive and negative ion registration modes. Thus, we are now able to measure the cometary H/C elemental ratio. Results. The mean H/C value is 1.04 ± 0.16 based on 33 different cometary particles. Consequently, the H/C atomic ratio is on average higher in cometary particles of 67P than in even the most primitive insoluble organic matter extracted from meteorites. Conclusions. These results imply that the refractory organic matter detected in dust particles of 67P is less unsaturated than the material in meteorites.

Micrometeorites (MMs) are small particles that account for most of the extraterrestrial material deposited on Earth. Synchrotron X-ray fluorescence and diffraction allowed for chemical and mineral characterization to distinguish MM from atmospheric particulate. The relative components of iron, nickel, and other elements were considered in the identification of ferrous MM while high amounts of titanium were considered an indication that the particles were of atmospheric origin. Out of 100 samples collected by high school students and teachers, eight were taken to a synchrotron for analysis. Of those eight, three exhibited extraterrestrial compositions. X-ray absorption near-edge structure analysis revealed that the same three samples contained sulfide, the main sulfur form constituent in MM. X-ray microdiffraction analysis showed the presence of the minerals pentlandite and forsterite. Collectively, these results support the extraterrestrial nature of the three particles.

Organic compounds are present as complex mixtures in extraterrestrial materials including meteorites, which may have played important roles in the origin of life on the primitive Earth. However, the distribution and formation mechanisms of meteoritic organic compounds are not well understood, because conventional analytical methods have limited resolution and sensitivity to resolve their molecular complexity. In this study, advanced instrumental development and analyses are proposed in order to study the trace organic compounds of extraterrestrial materials: (1) a clean room environment to avoid organic contamination during analysis; (2) high-mass-resolution analysis (up to ~150,000 m/m) coupled with high-performance liquid chromatography (HPLC) in order to determine the elemental composition using exact mass for inferring the chemical structure; (3) superior chromatographic separation using a two-dimensional system in order to determine the structural and optical isomers of amino acids; and (4) in situ organic compound analysis and molecular imaging of the sample surface. This approach revealed a higher complexity of organic compounds with a heterogeneous distribution in meteorites. These new methods can be applied to study the chemical evolution of meteoritic organic compounds as well as the molecular occurrence in very-low-mass extraterrestrial materials such as asteroid-returned samples.

Interplanetary Dust Particles (IDPs) are a relatively new class of extraterrestrial materials which are collected by high-flying aircraft in the stratosphere. The particles, ∼1.0-50 μm in size, enter the earth's atmosphere at ballistic velocities, but are sufficiently small to be decelerated without burning up. IDPs commonly have solar elemental abundances, and are thoughfto have undergone very little differentiation since the formation of the solar system. While these materials are called “particles,” they are in fact aggregates of a variety of mineral phases, glass, and carbonaceous material. Grains within IDPs commonly range from a few microns to a few tens of nanometers. The extraterrestrial origin of IDPs has been established by the discovery of solar flare tracks in some mineral grains, and recent D/H isotopic ratios recorded from individual particles. The source and formational history of the particles is a topic of active research. At present, the primary means of screening and classifying IDPs is Scanning Electron Microscopy, although a variety of electron microbeam and X-ray techniques is used for subsequent analysis.

La matière extraterrestre dite primitive se caractérise par sa faible évolution chimique depuis sa formation. Elle se retrouve notamment comme un des constituants des fragments de petits corps du système Solaire, tels que les astéroïdes. L'étude d'échantillons en provenance de ces corps peut ainsi permettre de mieux comprendre son origine et son évolution.Dans cette thèse, mon travail s'est orienté autour de l'analyse de la matière primitive et plus particulièrement sur l'étude des chondrites carbonées ayant subi de l'altération aqueuse. La première partie de ma thèse s'oriente sur l'analyse des phases minérales et organiques au sein de chondrites CM de type pétrologique 2 grâce à des techniques de spectroscopie infrarouge et Raman ainsi que de la spectrométrie de masse à ionisation secondaire par temps de vol (TOF-SIMS). Ces techniques bénéficient d'une bonne complémentarité dans la caractérisation des différentes phases qui nous intéressent. Elles sont également couplées à l'imagerie, ce qui permet d'étudier le lien qu'il peut exister entre les différentes phases minérales et organiques. J'ai utilisé un nouveau processus non supervisé d'analyse des données hyperspectrales infrarouge, ce qui a permis de déterminer des paramètres spectraux caractérisant l'état d'avancement de l'altération aqueuse des échantillons, notamment de leur phase minérale, tout en les reliant à leur évolution chimique. La spectroscopie Raman a permis de mettre en évidence des différences de structure de la matière organique poly-aromatique au sein des différents échantillons. Enfin, le TOF-SIMS a également mis en évidence une différence de structure de la matière organique tout en confirmant et précisant les différences de co-localisation entre matière organique et phase minérale observées par l'imagerie hyperspectrale entre les échantillons.La seconde partie de ma thèse s'est orientée sur l'étude d'efficacité d'un nouvel accélérateur linéaire - Andromede (IJCLab) - comme source primaire pour le TOF-SIMS sur des analogues à la matière primitive des chondrites. J'ai produit ces analogues organiques en laboratoire afin de simuler la matière organique insoluble, la part majoritaire de la matière organique des chondrites. J'ai contrôlé les caractéristiques de ces analogues par des spectroscopies infrarouges, à rayon X et par TOF-SIMS. Ils demeurent différents de la matière organique des CM en termes de structure poly-aromatique, mais similaires en termes de composition élémentaire et caractère insoluble. J'ai produit des analogues minéraux à partir de roches terrestres similaires aux minéraux rencontrés dans les CM. Les mesures que j'ai réalisées sur ces analogues et sur des chondrites montrent à la fois le potentiel et les limites actuelles du TOF-SIMS couplé à Andromède, et suggèrent des pistes d'amélioration en vue d'en augmenter, notamment, la résolution en masse
So-called primitive extraterrestrial matter is characterized by its low chemical evolution since its formation. It is found in particular as one of the constituents of the fragments of small bodies of the Solar system, such as asteroids. The study of samples from these bodies can thus make it possible to better understand its origin and its evolution.In this thesis, my work focused on the analysis of primitive matter and more particularly on the study of carbonaceous chondrites having undergone aqueous alteration. The first part of my thesis focuses on the analysis of mineral and organic phases within petrological type 2 CM chondrites using infrared and Raman spectroscopy techniques as well as time-of-flight secondary ionization mass spectrometry. (TOF-SIMS). These techniques benefit from a good complementarity in the characterization of the different phases that interest us. They are also coupled with imagery, which makes it possible to study the link that may exist between the different mineral and organic phases. I used a new unsupervised process for analyzing infrared hyperspectral data, which made it possible to determine spectral parameters characterizing the state of progress of the aqueous alteration of the samples, in particular of their mineral phase, while relating to their chemical evolution. Raman spectroscopy made it possible to highlight differences in the structure of the polyaromatic organic matter within the different samples. Finally, the TOF-SIMS also highlighted a difference in the structure of the organic matter while confirming and clarifying the differences in co-localization between organic matter and mineral phase observed by hyperspectral imaging between the samples.The second part of my thesis focused on the study of the effectiveness of a new linear accelerator - Andromeda (IJCLab) - as a primary source for TOF-SIMS on analogues of primitive chondrite matter. I produced these organic analogues in the laboratory to simulate insoluble organic matter, the majority of organic matter in chondrites. I checked the characteristics of these analogues by infrared spectroscopy, X-ray spectroscopy and TOF-SIMS. They remain different from CM organic matter in terms of poly-aromatic structure, but similar in terms of elemental composition and insoluble character. I have produced mineral analogues from earth rocks similar to minerals found in CM chondrite. The measurements that I carried out on these analogues and on chondrites show both the potential and the current limits of TOF-SIMS coupled to Andromede, and suggest areas for improvement with a view to increasing, in particular, the masse resolution

This article is an essay to analyze the movie “Dune” by Denis Villeneuve by using the concepts of imperialism, colonialism, and the quest for local justice. In Dune, the architectural elements selected for Arrakis, imperial palaces, and local living spaces of the future are all deeply in harmony with the planet’s landscape. The film matches the effective gliding of the source material in the book while dispensing with much of the novel by leaving behind David Lynch’s 1984 adaptation. The imperial/counterimperial and dominium battles between different space-conquering families set the basis of the story. The top family houses are scrambling and fighting for dominance. House Atreides has been assigned by the unseen Emperor to rule over Arrakis. <br><br>&nbsp;In almost every fiction art, designers, artists, and architects have labored to imagine what the state structure and/or built environment of an extraterrestrial world of the future might look like. The movie is directed by Denis Villeneuve, the talent/craftsmanship who presents sweeping vistas and startling science fiction imagery. Art director Vermette decided that the natural environments on each planet must be dominantly used in the design codes. In Arrakeen of Arrakis, the buildings depict a right angle choice. The dominant material is stone and light is taken in by “light wells”. Large windows are incapable of responding to super-extreme heat. All palaces in the movie are designed with the role of a monument to showcase and press the image of the Empire. By using a monumental scale, all characters are shown powerless and ineffective. A gigantic scale is used, not only in the palaces but also in the houses of families to demonstrate the storytelling mechanism in a power-coded socio-political order. The design of the music and soundscapes of different planets makes us feel the alien character.<br>

Space missions are conducted to gain an understanding of the universe and our solar system; to study the surface of planets other than earth; and to explore our extraterrestrial environment. Many of these missions travel to the far reaches of the solar system or explore regions that require a continuous source of electrical power that is more than what is available from the conversion of solar energy. For these space missions, electrical power is supplied by a radioisotope thermoelectric generator (RTG) that uses the heat generated by the decay radioactive material. The approval to launch and fly space vehicles using nuclear material is governed by Presidential Directive and requires authorization by the Executive Office of the President. As part of the launch approval process for these missions, a comprehensive safety analysis is conducted. This safety analysis employs a full-scope probabilistic risk assessment (PRA) to help identify improvement in launch and flight systems and quantify the risk associated with potential accidents and abort conditions during the mission. In general, the PRA follows a typical scenario-based assessment similar to PRAs that have been conducted for terrestrial hazardous facilities and operations. However, there are some significant differences when conducting a PRA of a space mission. This paper will provide a general overview of the PRA process as applied to nuclear space missions including; defining the analysis objective, system familiarization, accident sequence analysis, accident analysis, atmospheric transport, consequence analysis, and risk integration and uncertainty analysis.

ABSTRACT Deep space exploration is the frontier of the development of humanity. Investigators worldwide have conducted extensive research on the engineering characteristics and mineralogical composition of surface materials on the Moon, Mars, and asteroids, which have significant implications for future large-scale spacecraft soft landings and the construction of permanent bases. This work analyzes and summarizes a volume of previous findings on the engineering properties of the regolith of the Moon, Mars, and asteroid Ryugu, including the particle size distribution, bulk density, internal friction angle, cohesion, and presence of water ice. The methods used to obtain these properties are critically reviewed. We discuss their advantages and disadvantages and identify the potential new techniques that can be used to better constrain these engineering properties. This study can help researchers to understand the research progress on extraterrestrial regolith in the engineering properties, as well as prospective research directions in deep space exploration. INTRODUCTION Major government space agencies and private companies around the world, such as NASA, CNSA, and SpaceX, have launched ambitious deep space exploration programs to explore the evolution of the solar system and find a potential new habitat for mankind (Wu et al., 2012). Among the extraterrestrial celestial bodies in the solar system, Mars is the focus of the scientific community's attention due to its similarities to Earth (Li et al., 2021). Some key findings concerning Mars have been revealed by a series of probes, especially the landed ones such as InSight and Tianwen-1 (Zou et al., 2021). Due to the remote distance between Mars and Earth, the Moon is considered to be a springboard for Mars exploration (Crawford & Joy, 2014). Lunar exploration is the focus of current deep space exploration programs, including the Artemis program of the United States (Smith et al., 2020), the Chang’e (CE) Project of China (Li et al., 2019), and the Luna program of Russia (Djachkova et al., 2017). In addition, many asteroids have also attracted great interest from researchers, such as Ryugu, Bennu, 2016HO3, etc. (Zhang et al., 2022), and they also have a great chance to contribute to the solution to the evolution of the solar system.

This paper presents a design approach for developing meso-structure for high shear flexure in considering distribution of strain energy for a unit cell. Currently, flexible components are often designed with elastomers to take advantage of their unique properties of low shear modulus and high elongation. However, elastomers exhibit high loss modulus at a high frequency when they are subjected to cyclic loading. As a design requirement to find an alternative material in one of the sub systems in the extraterrestrial rover, materials with high elongation but low energy loss is investigated using a meso-structure design approach. In this paper, an approach to design a meso-structure exhibiting shear flexure is developed by conducting comparative studies of shear flexure on three equivalent configurations: auxetic, honeycomb, and sinusoidal. Based on this comparative study, a new hypothesis is proposed that specific strain energy distribution pattern in these meso-structure has a direct impact on the high shear flexure performance. This proposition is verified by developing a new meso-structure, termed ‘S’-Type, which is compared with auxetic and sinusoidal auxetic meso-structures on their shear flexure ability. It is shown from this comparative analysis that the ‘S’-Type meso-structure exhibits higher shear flexure than the other two meso-structures at 5, 10, 20, and 40 MPa of effective shear moduli. Hence, based on this result, a four-step design approach is proposed to design future meso-structures with high shear flexure.

The objective of this study is to develop an analytical method for the optimization of the design of the coring bits of vibratory drills with cutting teeth that percussively penetrate into brittle material. This optimization is intended to improve the drill rate of the Ultrasonic Driller and Corer (USDC) that was developed by scientists from JPL and engineers from Cybersonics, Inc. The USDC was developed for possible in-situ sample and other extraterrestrial applications in future NASA missions. A theoretical investigation was undertaken to study the rock-bit penetration characteristics and derive the analytical formulation of the specific energy for a coring bit with wedge-shape cutting teeth, based on two analytical models from rock fracture mechanics. It was found that there exists an optimal spacing/depth ratio for the cutting teeth, and the optimal number of cutting teeth on the bottom annulus of the coring bit can be designed to achieve a minimum total coring bit specific energy. Experimental tests were performed to corroborate the analytical results. It was shown that the laboratory drilling tests follow the trend predicted by the theoretical analysis. The methodology developed here can be used for the optimization of any coring/drill bit with a wedge-shape cutting teeth array in percussive/vibratory drills into brittle material.

We built a collector to filter interplanetary dust particles (IDPs) larger than 5 µm from the clean air at the Amundsen Scott South Pole station. Our sampling strategy used long duration, continuous dry filtering of near-surface air in place of short duration, high-speed impact collection on flags flown in the stratosphere. We filtered ~107 m³ of clean Antarctic air through 20 cm diameter, 3 µm filters coupled to a suction blower of modest power consumption (5–6 kW). Our collector ran continuously for 2 years and yielded 41 filters for analyses. Based on stratospheric concentrations, we predicted that each month’s collection would provide 300–900 IDPs for analysis. We identified 19 extraterrestrial (ET) particles on the 66 cm² of filter examined, which represented ~0.5% of the exposed filter surfaces. The 11 ET particles larger than 5 µm yield about a fifth of the expected flux based on >5 µm stratospheric ET particle flux. Of the 19 ET particles identified, four were chondritic porous IDPs, seven were FeNiS beads, two were FeNi grains, and six were chondritic material with FeNiS components. Most were <10 µm in diameter and none were cluster particles. Additionally, a carbon-rich candidate particle was found to have a small ¹⁵N isotopic enrichment, supporting an ET origin. Many other candidate grains, including chondritic glasses and C-rich particles with Mg and Si and FeS grains, require further analysis to determine if they are ET. The vast majority of exposed filter surfaces remain to be examined.