Publication
Names
  • Z. Dionnet
  • Z. Djouadi
  • L. Delaye
  • L. Caron
  • R. Brunetto
  • A. Aléon-Toppani
  • C. Lantz
  • S. Rubino
  • D. Baklouti
  • T. Nakamura
  • F. Borondics
  • C. Sandt
  • M. Matsumoto
  • K. Amano
  • T. Morita
  • H. Yurimoto
  • T. Noguchi
  • R. Okazaki
  • H. Yabuta
  • H. Naraoka
  • K. Sakamoto
  • S. Tachibana
  • T. Yada
  • M. Nishimura
  • A. Nakato
  • A. Miyazaki
  • K. Yogata
  • M. Abe
  • T. Okada
  • T. Usui
  • M. Yoshikawa
  • T. Saiki
  • S. Tanaka
  • F. Terui
  • S. Nakazawa
  • S. Watanabe
  • Y. Tsuda
Title
Methylene-to-methyl ratio variability in Ryugu samples: clues to a heterogeneous aqueous alteration.
Abstract
Understanding the processes of aqueous alteration within primitive bodies is crucial for unraveling the complex history of early planetesimals. To better identify the signs of this process and its consequences, we have studied led a study focused on the heterogeneity at a micrometric scale of the structure of the aliphatic organic compounds and its relationship to its mineralogical environment. Here we report an analysis performed on two micrometric grains of Ryugu (C0002-FC027 and C0002-FC028). The samples were crushed in a diamond compression cell and analyzed usingthanks to high-spatial resolution Fourier Transform InfraRed (FTIR) hyperspectral imaging measurements conducted in transmission mode. We show here the spatial distributions of the main components and the structural heterogeneity of the aliphatic organic matter highlighting a micrometer-scale variability in the methylene-to-methyl ratio. Moreover, we connected this heterogeneity to the one of the phyllosilicate band positions. Our findings indicate that the organic matter within Ryugu's micrometric grains underwent varying degrees of aqueous alteration in distinct microenvironments resulting to in an elongation of the length of their aliphatic chains, and/or a reduction in their branching and/or cross-linking.
Keywords
spectroscopy, imaging spectroscopy, FTIR spectrometer, Ryugu, mid-IR
Content
planetary sciences, spectral data, spectral data use
Year
2024
Journal
Meteoritics and Planetary Science
Volume
0
Pages
1
Pages number
16
Document type
article
Publication state
submitted