Chemical evolution of primordial salts and organic sulfur molecules in the asteroid 162173 Ryugu.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 37723151.
- Also identified by DOI 10.1038/s41467-023-40871-0 and PMC identifier 10507048.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Samples from the carbonaceous asteroid (162173) Ryugu provide information on the chemical evolution of organic molecules in the early solar system. Here we show the element partitioning of the major component ions by sequential extractions of salts, carbonates, and phyllosilicate-bearing fractions to reveal primordial brine composition of the primitive asteroid. Sodium is the dominant electrolyte of the salt fraction extract. Anions and NH<sub>4</sub><sup>+</sup> are more abundant in the salt fraction than in the carbonate and phyllosilicate fractions, with molar concentrations in the order SO<sub>4</sub><sup>2- </sup>> Cl<sup>- </sup>> S<sub>2</sub>O<sub>3</sub><sup>2- </sup>> NO<sub>3</sub><sup>- </sup>> NH<sub>4</sub><sup>+</sup>. The salt fraction extracts contain anionic soluble sulfur-bearing species such as S<sub>n</sub>-polythionic acids (n < 6), C<sub>n</sub>-alkylsulfonates, alkylthiosulfonates, hydroxyalkylsulfonates, and hydroxyalkylthiosulfonates (n < 7). The sulfur-bearing soluble compounds may have driven the molecular evolution of prebiotic organic material transforming simple organic molecules into hydrophilic, amphiphilic, and refractory S allotropes.