Processing of methane and acetylene ices by galactic cosmic rays and implications to the color diversity of Kuiper Belt objects

Autor: Chaojiang Zhang, Cheng Zhu, Andrew M. Turner, Ivan O. Antonov, Adrien D. Garcia, Cornelia Meinert, Leslie A. Young, David C. Jewitt, Ralf I. Kaiser
Přispěvatelé: University of Hawai‘i [Mānoa] (UHM), Institut de Chimie de Nice (ICN), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Southwest Research Institute [Boulder] (SwRI), Department of Earth and Space Sciences [Los Angeles], University of California [Los Angeles] (UCLA), University of California (UC)-University of California (UC), European Project: 804144,A-LIFE
Jazyk: angličtina
Rok vydání: 2023
Předmět:
Zdroj: Science Advances
Science Advances, 2023, 9 (22), pp.eadg6936. ⟨10.1126/sciadv.adg6936⟩
ISSN: 2375-2548
Popis: Kuiper Belt objects exhibit a wider color range than any other solar system population. The origin of this color diversity is unknown, but likely the result of the prolonged irradiation of organic materials by galactic cosmic rays (GCRs). Here, we combine ultrahigh-vacuum irradiation experiments with comprehensive spectroscopic analyses to examine the color evolution during GCR processing methane and acetylene under Kuiper Belt conditions. This study replicates the colors of a population of Kuiper Belt objects such as Makemake, Orcus, and Salacia. Aromatic structural units carrying up to three rings as in phenanthrene (C 14 H 10 ), phenalene (C 9 H 10 ), and acenaphthylene (C 12 H 8 ), of which some carry structural motives of DNA and RNA connected via unsaturated linkers, were found to play a key role in producing the reddish colors. These studies demonstrate the level of molecular complexity synthesized of GCR processing hydrocarbon and hint at the role played by irradiated ice in the early production of biological precursor molecules.
Databáze: OpenAIRE