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This study focuses on the development of a laser desorption/ionization mass spectrometric method for analyzing carbonaceous chondrites, meteorites that may hold clues to the origin of life. Since carbonaceous chondrites are only available in small quantities, we initially designed an artificial meteorite material (the mineral forsterite) doped with an organic material system (the amino acid tryptophan, the sugar 2-deoxy-D-ribose, and the polycyclic aromatic hydrocarbon triphenylene) as meteorite-like material to develop an LDI-MS method. This simulates a simplified artificial meteoritic composition to study the behavior of organic compounds in an inorganic environment. Experiments with meteorite-like material were performed on four different LDI-MS instruments (reflectron TOF-MS and QTOF-MS) with different performance characteristics (e.g., different lasers and laser repetition rates, different ion source pressure) in positive- and negative-ion mode and compared the data with those obtained on a TOF-SIMS instrument. Real meteoritic samples were also analyzed using our previously developed LDI-MS method and the TOF-SIMS method. For sample preparation, we used an in-house built micro-press, enabling the fixing of both meteorite-like material and real meteoritic splinters onto a target plate. Our unique target system, a universal in-house-designed adapter target holder, facilitated compatibility with all instruments including SIMS from different manufacturers. In the real meteorite samples a variety of elements, including potential detections of rubidium (85Rb:87Rb = 3:1), cesium (133Cs only), and tentatively holmium (165Ho only) was predominantly detected in positive-ion mode. Utilizing LDI with a reflectron TOF-MS in negative-ion mode, we identified distinct carbon clusters ranging from C2 to C13 in the Allende and Jbilet Winselwan meteorites originating most likely from high molecular weight organic carbon compounds. Background analysis confirmed a minimal impact of external contamination with carbon cluster ions validating the authenticity of these findings. No distinct other carbon-containing material could be identified.

Long-duration space missions beyond low Earth orbit pose increased risks of injury to astronauts. Traumatic hemorrhage will be a cause of preventable death. Due to payload constraints, in situ production of medical materials is essential. Regolith from the Moon, Mars, and asteroids is rich in silicates, which may serve as a hemostatic agent. Here, we aimed to evaluate whether extraterrestrial regolith simulants, their mineral components, and meteorites can activate coagulation through factor (F)XII and control bleeding. The procoagulant potential of Lunar and Martian regolith simulants, their component silicate minerals, and meteorite samples was assessed in vitro. Plasma clotting turbidity, thrombin generation, and FXIIa chromogenic assays were performed using either normal or FXII-inhibited/immunodepleted human plasma. ζ Potential and SiO2 content were also plotted against time to fibrin clot formation. The in vivo efficacy of Lunar highland simulant (CSM-LHT-1), Mars global simulant high clay (CSM-MGS-1C), and Northwest Africa-869 chondritic meteorite was assessed in a pilot study using a porcine model of penetrating hemorrhage. All extraterrestrial regolith simulant samples accelerated clotting, thrombin generation, and FXII activation in normal plasma, with reduced effects in FXII-immunodepleted or FXII-inhibited plasma. Phyllosilicates showed greater procoagulant activity than framework silicates. In vivo, wounds treated with regolith remained clotted longer and lost less blood than wounds treated with gauze alone, with the Northwest Africa-869 chondrite meteorite significantly improving clotting and reducing blood loss. Extraterrestrial regolith activated coagulation in a FXII-dependent manner and reduced blood loss in a trauma model of penetrating hemorrhage. This suggests that extraterrestrial regolith may be used as a hemostatic agent during space missions.

The uneven detection of prebiotic organic compounds in meteorites-where amino acids and nucleobases are commonly identified but sugars remain rare and poorly characterized-limits our understanding of extraterrestrial organic chemistry. This discrepancy is striking given that laboratory simulations of interstellar ice chemistry readily produce complex sugars. Here we report the simultaneous analysis of sugar and amino acid enantiomers in a meteorite sample. Multiple aldoses were detected in the Orgueil meteorite, including ribose, arabinose, xylose, lyxose, and the ketopentose ribulose, several of which display near-racemic distributions consistent with an extraterrestrial origin. Recovery experiments demonstrate that sugar abundances are severely underestimated. Despite this limitation, pentose abundances are comparable to those of some C4-C5 amino acid enantiomers, implying higher true concentrations. These results indicate efficient abiotic sugar formation in space and suggest that meteorites may have delivered a broader range of prebiotically relevant sugars to early Earth than previously recognized.

Quasicrystals, materials with long-range order but no periodicity, were first discovered in nature within the Khatyrka meteorite, a CV3 carbonaceous chondrite. Their occurrence demonstrated that hypervelocity impacts can generate quasiperiodic phases under transient conditions far from equilibrium, which survived for billions of years. Icosahedral and decagonal quasicrystals from Khatyrka formed at pressures exceeding 5 GPa and temperatures above 1200°C, as shown by their microstructures and association with shock-melted silicates and high-pressure polymorphs. Laboratory shock-recovery experiments reproduced these phases, confirming their synthesis during microsecond-scale shock pulses and their persistence after release. The presence of metallic aluminium, rarely stabilized in natural systems, indicates that extreme redox conditions are transiently established during impacts, enabling unusual alloy chemistries. Although rare in the meteoritic record, quasicrystals may be more widespread, their scarcity reflecting preservation biases and limited analytical focus on metallic phases. Advanced nanoscale diffraction and tomography methods, coupled with systematic surveys, are essential to uncover their distribution. Beyond meteorites, terrestrial craters, lunar breccias, Martian meteorites and asteroid samples are promising targets. Quasicrystals thus represent durable witnesses of impact processes, expanding the mineralogical tools for tracing high-energy events that shaped the early solar system.

Solar System bodies have similar abundances of non-volatile elements. Asteroids are categorized as unmelted chondritic bodies or as differentiated bodies formed by extensive to global melting of chondritic progenitors. Reflectance spectra show asteroids are compositionally similar to meteorites (which are composed of non-exotic materials-mainly silicates, metallic Fe-Ni, sulfides, oxides, and organic matter). Dense refractory siderophile elements (e.g., Re, Os, Ir, Pt) are present in iron meteorites in total concentrations&#x2009;<&#x2009;0.05&#xa0;wt%. The upper limit on the density of an asteroid is&#x2009;~&#x2009;8&#xa0;g&#xa0;cm-3 for a zero-porosity core fragment composed of&#x2009;~&#x2009;90&#xa0;wt% Fe and&#x2009;~&#x2009;10&#xa0;wt% Ni. Carry (Planet Space Sci 73:98-118, 2012) compiled asteroid densities and included some anomalous values (caused by uncertainties in measurement) that he characterized as unrealistic and non-physical. One such value for asteroid (33) Polyhymnia (75.3&#x2009;&#xb1;&#x2009;9.7&#xa0;g&#xa0;cm-3) was accepted by LaForge et al. (Eur Phys J Plus 138: 812, 2023) who characterized Polyhymnia as a compact ultradense object (CUDO) perhaps composed of stable superheavy elements (SHEs) or alpha matter (alpha particles in a Bose-Einstein condensate). Kiren et al. (Eur Phys J Plus 139: 547, 2024) proposed Polyhymnia could consist of degenerate dark matter. It is exceedingly unlikely that Polyhymnia or other asteroids contain exotic matter: (1) The listed bulk density of Polyhymnia is characterized as "unrealistic." (2) Meteorites (~&#x2009;98.5% are from asteroids) are composed of non-exotic materials. (3) The spectra of "CUDO" asteroids do not differ from other asteroids of their taxonomic class. (4) SHEs and degenerate dark matter have not yet been shown to exist. (5) Alpha matter may occur naturally only in extreme astrophysical environments.

Polycyclic aromatic hydrocarbons (PAHs) represent key molecular building blocks of carbonaceous nanoparticles and have been identified in cold molecular clouds (TMC-1), meteorites (Murchison, Allende), and asteroids (Bennu, Ryugu). However, the understanding of their formation and molecular mass growth processes in these extreme environments has remained elusive, especially with the emergence of resonantly-stabilized free radical (RSFR)-mediated pathways. Here, we report a combined experimental and computational study on the self-recombination of the aromatic and resonantly-stabilized 1-indenyl radical (C9H7 &#x2022;) isomer-selectively forming the 18&#x3c0;-H&#xfc;ckel PAH chrysene (C18H12) in an overall endoergic reaction. These features account for the circumstellar origin of chrysene in pristine samples of the carbonaceous asteroid Ryugu and of the Murchison meteorite. At the microscopic level, the ring expansion involving cyclopentadienyl moieties to two six-membered aromatic rings via pivotal spiroaromatic intermediates affords a versatile, RSFR-initiated mass growth channel essentially leading to graphene-type PAHs and eventually two-dimensional nanostructures in high temperature circumstellar envelopes and in combustion processes.

This review of martian organic geochemistry aims to contextualize recent findings of organic molecules in martian meteorites and from Mars missions within the broader study of origins of life on Earth. Analyzing martian organic inventories helps us understand the abiotic processes in planetary environments that are common wherever rocks interact with liquid brines and that likely contributed to the emergence of life on Earth. Mars is only the second planetary body studied for organic molecules; while carbonaceous meteorites, comet missions, and sample-return analyses of comets and asteroids have shown the diversity of organics across the solar system, studying Mars reveals what these molecules are on another planet. Although a definitive sign of extraterrestrial life has not yet been found, the findings provide insights into abiotic synthesis mechanisms that would have occurred on early Earth. At worst, these observations represent the oldest planetary record of organic and prebiotic chemical synthesis pathways that could have led to life, as inferred from the alteration of Earth's oldest rocks. They may also point to potential habitats for past martian life. Currently, samples collected by the Perseverance rover represent a unique opportunity to verify which of the two questions, "Are we alone?" or "How did we get here?" will be true for Mars. Without doubt, these questions would be best addressed through the use of higher resolution analyses by more advanced and sensitive instrumentation after sample return to Earth. Even if no definitive signs of life are found in returned samples, they would give us the opportunity to study the missing link to life on Earth, that of the primordial abiotic organic chemical processes that could have led to life. Therefore, there are no wrong answers to exploring Mars for signs of life; its secrets will illuminate our understanding of ourselves and our place in the universe, whatever the answer.

Characterizing organic compounds using STEM-EELS at high spatial resolution is crucial in materials science and geosciences, especially for organics intricately mixed with minerals at the nanoscale, as is the case in carbonaceous meteorites. However, the high spatial resolution provided by TEM comes with the challenge of electron beam sensitivity, which has long hindered the study of these fragile compounds. Here, we take advantage of direct electron detectors to revisit analytical strategies, searching for the best compromise to prevent beam damage and reach the highest spatial resolution. Our STEM-EELS parametric survey focuses on two reference polymers (PEEK and PES) which differ in their molecular structures and susceptibility to radiation-induced damage. We sequentially acquire low loss and carbon K-edge spectra at low dwell time using a multi-frame protocol, possible thanks to noiseless direct electron detectors. Results show that PES is much more sensitive than PEEK and that the main damage mechanism is radiolysis coupled to recombination. Damage rates are lower when working at an accelerating voltage of 200 keV rather than at 80 keV. Cooling the sample (- 100 &#xb0;C) helps reducing mass loss and amorphization, but can also lead to the formation of undesired functional groups through recombination. The pixel size affects beam damage independently of the electron dose. Using the fastest dwell-time permitted by the detectors (80 &#xb5;s) and pixel sizes of 1.5, 7.5, 15 and 30 nm, we show that PEEK resists at 15 nm pixel but is rapidly amorphized at 1 nm while PES is already unstable at 30 nm pixel size. We understand this as damage delocalization effect on successive pixels. The insoluble organic matter extracted from the Orgueil meteorite also appears to better resist damages at 200 keV, but its aliphatic groups are nevertheless affected at pixel size of 15 nm. A reasonable spectral agreement is found between STEM-EELS and synchrotron-based XANES-STXM, paving the road for investigating extra-terrestrial samples such as those returned by space mission from carbonaceous asteroids Ryugu and Bennu.

The recent discovery of all five canonical nucleobases in samples from Bennu provides compelling evidence that some of life's ingredients were synthesized abiotically in the parent body of this asteroid and/or its precedent components. However, due to the sample availability and the limited method for the analysis, the detailed distribution of nucleobases in the samples remains elusive. Here we report the concentrations of a diverse suite of nitrogen (N)-heterocycles including nucleobases extracted by 2% and 20% hydrochloric acid from a homogenized Bennu sample. The detection of both canonical and non-canonical nucleobase pairs confirms that these biologically important compounds are extraterrestrial. Pyrimidines are more abundant than purines-like the Orgueil meteorite, but unlike the Murchison meteorite and asteroid Ryugu samples-suggesting preferential synthesis in ammonia-rich ices from the outer Solar System. The distribution of other N-heterocycles is consistent with extensive aqueous alteration on the parent body. High concentrations of urea underscore its role in N-heterocycle synthesis. Our findings offer important information on the prebiotic inventory of N-heterocycles in the Solar System.

149Sm-150Sm and 157Gd-158Gd isotopic shifts of solar planetary materials caused by neutron capture reactions have been utilized to characterize the cosmic-ray exposure (CRE) conditions of the individual materials in space. This paper reviews the results of Sm and Gd isotopic shifts for four kinds of planetary materials: enstatite chondrites (aubrites), iron and iron meteorites, lunar soils, and lunar meteorites, and their application with a view to understanding the relationship between the CRE histories and the evolution processes for individual planetary materials as addressed in my previous studies.

We have explored the reactions of a three-components mixture made of formamide, diaminomaleonitrile, and glycine, with meteorites as catalysts and high-energy proton beam irradiation as the energy source, mimicking the solar wind. The resulting mixture contained a wide array of biogenic compounds, including the complete set of RNA nucleobases and nucleosides, thymine and its analogs, pterins, triazines, carboxylic acids, diketopiperazines, hydantoins, N-carboxyamino acid anhydrides, amino acids, peptides, and nucleobase-amino acid/peptide conjugates. It also embodies the possibility of synthesis stability of RNA-peptide chimeras onto which evolution to the extant molecular genetic system could start. The prebiotic worth of the system consists of the fact that formamide derives from HCN hydrolysis; glycine is a condensation product of formamide and HCN; diaminomaleonitrile is obtained from HCN. The fact that the starting mixture is three-component does not decrease the prebiotic value; it is a subset of a largely possible general universal condition: all the starting components are only the second step of facile condensation reactions. This model could be the starting point for the chemical evolution towards biological complexity.

This article reviews the early history of our solar system from an astrobiological perspective and presents evidence from meteorites and astronomical observations. The purpose is to trace the formation of key molecules that participated in the building blocks of life. The Sun and its planetary system started from a section of a molecular cloud that collapsed into a protoplanetary disk. In the center of the protoplanetary disk, the protosun heated the surrounding material. The dust and gas inherited from the cloud remained pristine farther away from the protostar, while new compounds were created in the gas and on the icy mantles of the dust. The dust accreted into pebbles, pebbles formed planetesimals, and planetesimals collided and accreted pebbles to create planets. Meanwhile, the protosun became the Sun when its core reached the pressure and temperature required to transform hydrogen into helium. During this process, the Sun emitted high-energy radiation and particles that impacted the chemistry in the disk and the early evolution of the terrestrial planets.

The composition of Earth's Fe-rich liquid outer core has long been debated. Available models incorporating light elements, such as Si, O, C, S, and H, cannot explain the seismically low velocity layer in the uppermost outer core (E' layer). Here we employ first-principles molecular dynamics simulations to determine the density and sound velocity ( V P ) of Fe-Mg liquids under outer core conditions, which were unknown previously. Results show that the presence of Mg slightly decreases the V P of liquid Fe, in contrast to the enhancing effects of other light elements. Our modeling suggests that 0.5-1.79&#x2009;wt% Mg is required to match seismically observed core densities and velocities. Such amount of Mg could have entered the outermost outer core following the Moon-forming giant impact, thereby providing a viable explanation for the formation of the E' layer and contributing to the slight Mg depletion in the bulk silicate Earth relative to chondritic meteorites.