Infrared absorption spectra from organic matter in the asteroid Ryugu samples: Some unique properties compared to unheated carbonaceous chondrites
Yoko Kebukawa, Eric Quirico, Emmanuel Dartois, Hikaru Yabuta, Laure Bejach, Lydie Bonal, Alexandre Dazzi, Ariane Deniset-Besseau, Jean Duprat, Cecile Engrand, Jérémie Mathurin, Jens Barosch, George D. Cody, Bradley De Gregorio, Minako Hashiguchi, Kanami Kamide, David Kilcoyne, Mutsumi Komatsu, Zita Martins, Gilles Montagnac, Smail Mostefaoui, Larry R. Nittler, Takuji Ohigashi, Taiga Okumura, Laurent Remusat, Scott Sandford, Miho Shigenaka, Rhonda Stroud, Hiroki Suga, Yoshio Takahashi, Yasuo Takeichi, Yusuke Tamenori, Maximilien Verdier-Paoletti, Daisuke Wakabayashi, Shohei Yamashita, Hisayoshi Yurimoto, Tomoki Nakamura, Takaaki Noguchi, Ryuji Okazaki, Hiroshi Naraoka, Kanako Sakamoto, Shogo Tachibana, Toru Yada, Masahiro Nishimura, Aiko Nakato, Akiko Miyazaki, Kasumi Yogata, Masanao Abe, Tatsuaki Okada, Tomohiro Usui, Makoto Yoshikawa, Takanao Saiki, Satoshi Tanaka, Fuyuto Terui, Satoru Nakazawa, Sei-ichiro Watanabe, Yuichi Tsuda
MAPS
Version of Record online: 19 August 2023
“The infrared spectral characteristics of organic-rich acid residues prepared from Ryugu samples returned by the JAXA Hayabusa2 mission generally match those from unheated carbonaceous chondrite meteorites, but the residues from Ryugu are richer in methyl and methylene functional groups and have higher CH2/CH3 ratios. Moreover, two distinct outlier carbonaceous phases are found; one with spectral characteristics of N-H functional groups, likely amides, and a second phase containing less nitrogen. Such infrared characteristics of Ryugu organic matter might indicate the pristine nature of the freshly collected samples and reflect the near-surface chemistry in the parent asteroid.”