Publications by authors named "H H MCLAIN"
Titan is an ocean world with a plethora of organic material in its atmosphere and on its surface, making it an intriguing location in the search for habitable environments beyond Earth. Settled aerosols will mix with transient surface melts following cryovolcanic eruptions and impact events, driving hydrolysis reactions and prebiotic chemistry. Previous studies have shown that the hydrolysis of laboratory-synthesized Titan organics leads to the production of amino acids and other prebiotic molecules.
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- * The research simulated the aqueous alteration processes of residues from irradiated interstellar ice, using minerals like serpentinite and the Allende meteorite to study amino acid changes.
- * Results showed that minerals and their types crucially affect the creation and breakdown of amino acids during these simulated experiments.
Europa and Enceladus are key targets to search for evidence of life in our solar system. However, the surface and shallow subsurface of both airless icy moons are constantly bombarded by ionizing radiation that could degrade chemical biosignatures. Therefore, sampling of icy surfaces in future life detection missions to Europa and Enceladus requires a clear understanding of the necessary ice depth where unaltered organic biomolecules might be present.
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- Polycyclic aromatic hydrocarbons (PAHs) make up about 20% of carbon in the interstellar medium and can form under various conditions, including in hot circumstellar environments and cold interstellar clouds.
- Isotopic analysis of PAHs from asteroid Ryugu and meteorite Murchison shows that some PAHs, like naphthalene, fluoranthene, and pyrene, have higher carbon isotopic values than expected, indicating they likely formed in the interstellar medium rather than in hot environments.
- In contrast, the PAHs phenanthrene and anthracene from Ryugu display isotopic values that suggest they were formed through higher-temperature reactions.
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.
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