Late fluid flow in a primitive asteroid revealed by Lu-Hf isotopes in Ryugu

• 成果类型: Article
• 署名作者: Iizuka, Tsuyoshi; Shibuya, Takazo; Hayakawa, Takehito; Yokoyama, Tetsuya; Gautam, Ikshu; Haba, Makiko K.; Ito, Kengo T. M.; Hibiya, Yuki; Yamaguchi, Akira; Abe, Yoshinari; Aleon, Jerome; Alexander, Conel M. O'D.; Amari, Sachiko; Amelin, Yuri; Bajo, Ken-ichi; Bizzarro, Martin; Bouvier, Audrey; Carlson, Richard W.; Chaussidon, Marc; Choi, Byeon-Gak; Dauphas, Nicolas; Davis, Andrew M.; Di Rocco, Tommaso; Fujiya, Wataru; Fukai, Ryota; Hidaka, Hiroshi; Homma, Hisashi; Huss, Gary R.; Ireland, Trevor R.; Ishikawa, Akira; Itoh, Shoichi; Kawasaki, Noriyuki; Kita, Noriko T.; Kitajima, Koki; Kleine, Thorsten; Komatani, Shintaro; Krot, Alexander N.; Liu, Ming-Chang; Masuda, Yuki; Motomura, Kazuko; Moynier, Frederic; Nagashima, Kazuhide; Nakai, Izumi; Nguyen, Ann; Nittler, Larry; Pack, Andreas; Park, Changkun; Piani, Laurette; Qin, Liping; Russell, Sara; Sakamoto, Naoya; Schonbachler, Maria; Tafla, Lauren; Tang, Haolan; Terada, Kentaro; Terada, Yasuko; Usui, Tomohiro; Wada, Sohei; Wadhwa, Meenakshi; Walker, Richard J.; Yamashita, Katsuyuki; Yin, Qing-Zhu; Yoneda, Shigekazu; Yui, Hiroharu; Zhang, Ai-Cheng; Nakamura, Tomoki; Naraoka, Hiroshi; Noguchi, Takaaki; Okazaki, Ryuji; Sakamoto, Kanako; Yabuta, Hikaru; Abe, Masanao; Miyazaki, Akiko; Nakato, Aiko; Nishimura, Masahiro; Okada, Tatsuaki; Yada, Toru; Yogata, Kasumi; Nakazawa, Satoru; Saiki, Takanao; Tanaka, Satoshi; Terui, Fuyuto; Tsuda, Yuichi; Watanabe, Sei-ichiro; Yoshikawa, Makoto; Tachibana, Shogo; Yurimoto, Hisayoshi
• 署名单位: University of Tokyo; Japan Agency for Marine-Earth Science & Technology (JAMSTEC); National Institutes for Quantum Science & Technology; Institute of Science Tokyo; University of Tokyo; University of Tokyo; Japan Agency for Marine-Earth Science & Technology (JAMSTEC); Research Organization of Information & Systems (ROIS); National Institute of Polar Research (NIPR) - Japan; Graduate University for Advanced Studies - Japan; Tokyo Denki University; Institut de Recherche pour le Developpement (IRD); Centre National de la Recherche Scientifique (CNRS); Sorbonne Universite; Museum National d'Histoire Naturelle (MNHN); Universite Paris Cite; CNRS - Institute of Physics (INP); Carnegie Institution for Science; Washington University (WUSTL); Washington University (WUSTL); Korea Basic Science Institute (KBSI); Hokkaido University; University of Copenhagen; University of Bayreuth; Universite Paris Cite; Centre National de la Recherche Scientifique (CNRS); Seoul National University (SNU); University of Chicago; University of Chicago; University of Gottingen; Ibaraki University; Japan Aerospace Exploration Agency (JAXA); Institute of Space & Astronautical Science (ISAS); Nagoya University; Rigaku Corporation; University of Hawaii System; University of Hawaii Manoa; University of Queensland; Kyoto University; Hokkaido University; Max Planck Society; University of California System; University of California Los Angeles; Rigaku Corporation; Tokyo University of Science; National Aeronautics & Space Administration (NASA); Korea Polar Research Institute (KOPRI); Centre National de la Recherche Scientifique (CNRS); Universite de Lorraine; Chinese Academy of Sciences; University of Science & Technology of China, CAS; Natural History Museum London; Hokkaido University; Swiss Federal Institutes of Technology Domain; ETH Zurich; University of Osaka; Japan Synchrotron Radiation Research Institute; Arizona State University; Arizona State University-Tempe; University System of Maryland; University of Maryland College Park; Okayama University; University of California System; University of California Davis; National Museum of Nature and Science; Tokyo University of Science; Nanjing University; Tohoku University; Kyushu University; Hiroshima University; Kanagawa Institute Technology; University of Tokyo
• 刊物名称: NATURE
• ISSN/ISSBN: 0028-0836; 1476-4687
• DOI: 10.1038/s41586-025-09483-0
• 发表日期: 2025-10-02
• 关键词: molal thermodynamic properties; early solar-system; s-process; high-pressures; transport-properties; excess hf-176; nd; chondrites; temperatures; meteorites

摘要

Carbonaceous asteroids are the source of the most primitive meteorites1 and represent leftover planetesimals that formed from ice and dust in the outer Solar System and may have delivered volatiles to the terrestrial planets2, 3, 4-5. Understanding the aqueous activity of asteroids is key to deciphering their thermal, chemical and orbital evolution, with implications for the origin of water on the terrestrial planets. Analyses of the objects, in particular pristine samples returned from asteroid Ryugu, have provided detailed information on fluid-rock interactions within a few million years after parent-body formation6, 7, 8, 9, 10-11. However, the long-term fate of asteroidal water remains poorly understood. Here we present evidence for fluid flow in a carbonaceous asteroid more than 1 billion years after formation, based on the 176Lu-176Hf decay systematics of Ryugu samples, which reflect late lutetium mobilization. Such late fluid flow was probably triggered by an impact that generated heat for ice melting and opened rock fractures for fluid migration. This contrasts the early aqueous activity powered by short-lived radioactive decay, with limited fluid flow and little elemental fractionation12. Our results imply that carbonaceous planetesimals accreted by the terrestrial planets could have retained not only hydrous minerals but also aqueous water, leading to an upwards revision of the inventory of their water delivery by a factor of two to three.