The Hayabusa2 spacecraft collected samples from the surface of the carbonaceous near-Earth asteroid (162173) Ryugu and brought them to Earth. The samples were expected to contain organic molecules, which record processes that occurred in the early Solar System. We analyzed organic molecules extracted from the Ryugu surface samples. We identified a variety of molecules containing the atoms CHNOS, formed by methylation, hydration, hydroxylation, and sulfurization reactions. Amino acids, aliphatic amines, carboxylic acids, polycyclic aromatic hydrocarbons, and nitrogen-heterocyclic compounds were detected, which had properties consistent with an abiotic origin. These compounds likely arose from an aqueous reaction on Ryugu’s parent body and are similar to the organics in Ivuna-type meteorites. These molecules can survive on the surfaces of asteroids and be transported throughout the Solar System.

Polycyclic aromatic hydrocarbons (PAHs) contain ≲20% of the carbon in the interstellar medium. They are potentially produced in circumstellar environments (at temperatures ≳1000 kelvin), by (~10 kelvin) interstellar clouds, or by processing of carbon-rich dust grains. We report isotopic properties of PAHs extracted from samples of the asteroid Ryugu and the meteorite Murchison. The doubly- ¹³ C substituted compositions (Δ2× ¹³ C values) of the PAHs naphthalene, fluoranthene, and pyrene are 9 to 51‰ higher than values expected for a stochastic distribution of isotopes. The Δ2× ¹³ C values are higher than expected if the PAHs formed in a circumstellar environment, but consistent with formation in the interstellar medium. By contrast, the PAHs phenanthrene and anthracene in Ryugu samples have Δ2× ¹³ C values consistent with formation by higher-temperature reactions.

Astrochemistry, meteoritics and chemical analytics represent a manifold scientific field, including various disciplines. In this review, clarifications on astrochemistry, comet chemistry, laboratory astrophysics and meteoritic research with respect to organic and metalorganic chemistry will be given. The seemingly large number of observed astrochemical molecules necessarily requires explanations on molecular complexity and chemical evolution, which will be discussed. Special emphasis should be placed on data-driven analytical methods including ultrahigh-resolving instruments and their interplay with quantum chemical computations. These methods enable remarkable insights into the complex chemical spaces that exist in meteorites and maximize the level of information on the huge astrochemical molecular diversity. In addition, they allow one to study even yet undescribed chemistry as the one involving organomagnesium compounds in meteorites. Both targeted and non-targeted analytical strategies will be explained and may touch upon epistemological problems. In addition, implications of (metal)organic matter toward prebiotic chemistry leading to the emergence of life will be discussed. The precise description of astrochemical organic and metalorganic matter as seeds for life and their interactions within various astrophysical environments may appear essential to further study questions regarding the emergence of life on a most fundamental level that is within the molecular world and its self-organization properties.

We report a huge organic diversity in the Tissint Mars meteorite and the sampling of several mineralogical lithologies, which revealed that the organic molecules were nonuniformly distributed in functionality and abundance. The range of organics in Tissint meteorite were abundant C _3-7 aliphatic branched carboxylic acids and aldehydes, olefins, and polyaromatics with and without heteroatoms in a homologous oxidation structural continuum. Organomagnesium compounds were extremely abundant in olivine macrocrystals and in the melt veins, reflecting specific organo-synsthesis processes in close interaction with the magnesium silicates and temperature stresses, as previously observed. The diverse chemistry and abundance in complex molecules reveal heterogeneity in organic speciation within the minerals grown in the martian mantle and crust that may have evolved over geological time.

Context. Sulfur (S) is of prime interest in the context of (astro)chemical evolution and habitability. However, the origin of S-bearing organic compounds in the Solar System is still not well constrained. Aims. We carried out laboratory experiments to test whether complex organosulfur compounds can be formed when surfaces of icy Solar System bodies are subject to high-energy S ions. Methods. Non-S-bearing organic residues, formed during the processing of astrophysical H₂O:CH₃OH:NH₃-bearing ice analogs, were irradiated with 105 keV-S⁷⁺ ions at 10 K and analyzed by high-resolving FT-ICR-MS. The resulting data were comprehensively analyzed, including network analysis tools. Results. Out of several thousands of detected compounds, 16% contain at least one sulfur atom (organosulfur (CHNOS) compounds), as verified via isotopic fine structures. These residue-related organosulfur compounds are different from those formed during the S ion irradiation of ices at 10 K. Furthermore, insoluble, apolar material was formed during the sulfur irradiation of residues. Potential organosulfur precursors (CHNO molecules) were identified by means of molecular networks. Conclusions. This evidence of organosulfur compounds formed by sulfur irradiation of organic residues sheds new light onto the rich and complex scope of pristine organosulfur chemistry in the Solar System, presented in the context of current and future space missions. These results indicate that the space weathering of Solar System bodies may lead to the formation of organosulfur compounds.