The spatial distribution of soluble organic matter and their relationship to minerals in the asteroid (162173) Ryugu - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Earth Planets and Space Année : 2023

The spatial distribution of soluble organic matter and their relationship to minerals in the asteroid (162173) Ryugu

Minako Hashiguchi
Dan Aoki
  • Fonction : Auteur
Aogu Furusho
  • Fonction : Auteur
Kenji Hamase
  • Fonction : Auteur
Roland Thissen
Takaaki Noguchi
  • Fonction : Auteur
Ryuji Okazaki
  • Fonction : Auteur

Résumé

Abstract We performed in-situ analysis on a ~ 1 mm-sized grain A0080 returned by the Hayabusa2 spacecraft from near-Earth asteroid (162173) Ryugu to investigate the relationship of soluble organic matter (SOM) to minerals. Desorption electrospray ionization-high resolution mass spectrometry (DESI-HRMS) imaging mapped more than 200 CHN, CHO, CHO–Na (sodium adducted), and CHNO soluble organic compounds. A heterogeneous spatial distribution was observed for different compound classes of SOM as well as among alkylated homologues on the sample surface. The A0080 sample showed mineralogy more like an Ivuna-type (CI) carbonaceous chondrite than other meteorites. It contained two different lithologies, which are either rich (lithology 1) or poor (lithology 2) in magnetite, pyrrhotite, and dolomite. CHN compounds were more concentrated in lithology 1 than in lithology 2; on the other hand, CHO, CHO–Na, and CHNO compounds were distributed in both lithologies. Such different spatial distribution of SOM is likely the result of interaction of the SOM with minerals, during precipitation of the SOM via fluid activity, or could be due to difference in transportation efficiencies of SOMs in aqueous fluid. Organic-related ions measured by time-of-flight secondary ion mass spectrometry (ToF–SIMS) did not coincide with the spatial distribution revealed by DESI-HRMS imaging. This result may be because the different ionization mechanism between DESI and SIMS, or indicate that the ToF–SIMS data would be mainly derived from methanol-insoluble organic matter in A0080. In the Orgueil meteorite, such relationship between altered minerals and SOM distributions was not observed by DESI-HRMS analysis and field-emission scanning electron microscopy, which would result from differences of SOM formation processes and sequent alteration process on the parent bodies or even on the Earth. Alkylated homologues of CHN compounds were identified in A0080 by DESI-HRMS imaging as observed in the Murchison meteorite, but not from the Orgueil meteorite. These compounds with a large C number were enriched in Murchison fragments with abundant carbonate grains. In contrast, such relationship was not observed in A0080, implying different formation or growth mechanisms for the alkylated CHN compounds by interaction with fluid and minerals on the Murchison parent body and asteroid Ryugu. Graphical Abstract
Fichier principal
Vignette du fichier
s40623-023-01792-w.pdf (13.19 Mo) Télécharger le fichier
Origine Fichiers éditeurs autorisés sur une archive ouverte
Licence

Dates et versions

hal-04420435 , version 1 (09-02-2024)

Licence

Identifiants

Citer

Minako Hashiguchi, Dan Aoki, Kazuhiko Fukushima, Hiroshi Naraoka, Yoshinori Takano, et al.. The spatial distribution of soluble organic matter and their relationship to minerals in the asteroid (162173) Ryugu. Earth Planets and Space, 2023, 75 (1), pp.73. ⟨10.1186/s40623-023-01792-w⟩. ⟨hal-04420435⟩
47 Consultations
8 Téléchargements

Altmetric

Partager

Gmail Mastodon Facebook X LinkedIn More