太陽系科学研究系

安部 正真

アベ マサナオ  (Masanao Abe)

基本情報

所属
国立研究開発法人宇宙航空研究開発機構 宇宙科学研究所 太陽系科学研究系 准教授

研究者番号
00270439
ORCID ID
 https://orcid.org/0000-0003-4780-800X
J-GLOBAL ID
200901004756228297
researchmap会員ID
5000050882

論文

 169
  • Larry R Nittler, Jens Barosch, Katherine Burgess, Rhonda M Stroud, Jianhua Wang, Hikaru Yabuta, Yuma Enokido, Megumi Matsumoto, Tomoki Nakamura, Yoko Kebukawa, Shohei Yamashita, Yoshio Takahashi, Laure Bejach, Lydie Bonal, George D Cody, Emmanuel Dartois, Alexandre Dazzi, Bradley De Gregorio, Ariane Deniset-Besseau, Jean Duprat, Cécile Engrand, Minako Hashiguchi, A.L. David Kilcoyne, Mutsumi Komatsu, Zita Martins, Jérémie Mathurin, Gilles Montagnac, Smail Mostefaoui, Taiga Okumura, Eric Quirico, Laurent Remusat, Scott Sandford, Miho Shigenaka, Hiroki Suga, Yasuo Takeichi, Yusuke Tamenori, Maximilien Verdier-Paoletti, Daisuke Wakabayashi, Masanao Abe, Kanami Kamide, Akiko Miyazaki, Aiko Nakato, Satoru Nakazawa, Masahiro Nishimura, Tatsuaki Okada, Takanao Saiki, Satoshi Tanaka, Fuyuto Terui, Tomohiro Usui, Toru Yada, Kasumi Yogata, Makoto Yoshikawa, Hisayoshi Yurimoto, Takaaki Noguchi, Ryuji Okazaki, Hiroshi Naraoka, Kanako Sakamoto, Shogo Tachibana, Sei-ichiro Watanabe, Yuichi Tsuda
    Earth and Planetary Science Letters 637 118719-118719 2024年7月  
  • Naoya Imae, Naotaka Tomioka, Masayuki Uesugi, Makoto Kimura, Akira Yamaguchi, Motoo Ito, Richard C. Greenwood, Tatsuya Kawai, Naoki Shirai, Takuji Ohigashi, Cedric Pilorget, Jean‐Pierre Bibring, Ming‐Chang Liu, Kentaro Uesugi, Aiko Nakato, Kasumi Yogata, Hayato Yuzawa, Yu Kodama, Masahiro Yasutake, Kaori Hirahara, Akihisa Takeuchi, Ikuya Sakurai, Ikuo Okada, Yuzuru Karouji, Toru Yada, Masanao Abe, Tomohiro Usui
    Meteoritics & Planetary Science 2024年5月10日  
    Abstract Although CI chondrites are susceptible to terrestrial weathering on Earth, the specific processes are unknown. To elucidate the weathering mechanism, we conduct a laboratory experiment using pristine particles from asteroid Ryugu. Air‐exposed particles predominantly develop small‐sized euhedral Ca‐S‐rich grains (0.5–1 μm) on the particle surface and along open cracks. Both transmission electron microscopy and synchrotron‐based computed tomography combined with XRD reveal that the grains are hydrous Ca‐sulfate. Notably, this phase does not form in vacuum‐ or nitrogen‐stored particles, suggesting this result is due to laboratory weathering. We also compare the Orgueil CI chondrite with the altered Ryugu particles. Due to the weathering of pyrrhotite and dolomite, Orgueil contains a significant amount of gypsum and ferrihydrite. We suggest that mineralogical changes due to terrestrial weathering of particles returned directly from asteroid occur even after a short‐time air exposure. Consequently, conducting prompt analyses and ensuring proper storage conditions are crucial, especially to preserve the primordial features of organics and volatiles.
  • Ko Hashizume, Akizumi Ishida, Ayano Chiba, Ryuji Okazaki, Kasumi Yogata, Toru Yada, Fumio Kitajima, Hisayoshi Yurimoto, Tomoki Nakamura, Takaaki Noguchi, Hikaru Yabuta, Hiroshi Naraoka, Yoshinori Takano, Kanako Sakamoto, Shogo Tachibana, Masahiro Nishimura, Aiko Nakato, Akiko Miyazaki, Masanao Abe, Tatsuaki Okada, Tomohiro Usui, Makoto Yoshikawa, Takanao Saiki, Fuyuto Terui, Satoshi Tanaka, Satoru Nakazawa, Sei‐ichiro Watanabe, Yuichi Tsuda, Michael W. Broadley, Henner Busemann
    Meteoritics & Planetary Science 2024年4月30日  
    Abstract The nitrogen isotope compositions of two samples returned from the asteroid Ryugu were determined using a stepwise combustion method, along with Ivuna (CI) and Y‐980115, a CI‐like Antarctic meteorite, as references. The two Ryugu samples A0105‐07 and C0106‐07 showed bulk δ15N values of +1.7 ± 0.5‰ and +0.2 ± 0.6‰, respectively, significantly lower than Ivuna with +36.4 ± 0.4‰, but close to Y‐980115 with +4.0 ± 0.3‰. The Ryugu samples are further characterized by C/N and 36Ar/N ratios up to 3.4× and 4.9× the value of Ivuna, respectively. Among all Ryugu samples and CI chondrites, a positive correlation was observed between nitrogen concentrations and δ15N values, with samples with lower nitrogen concentrations exhibiting lower δ15N. This trend is explained by a two‐component mixing model. One component is present at a constant abundance among all CI‐related samples, with a δ15N value around 0‰ or lower. The other varies in abundance between different samples, and exhibits a δ15N value of +56 ± 4‰. The first 15N‐poor endmember is seemingly tightly incorporated into a carbonaceous host phase, whereas the 15N‐rich endmember can be mobilized and decoupled from carbon, potentially because it is in the form of ammonia. Asteroid materials with volatile compositions that are similar to those reported here for the Ryugu samples are attractive candidates for the volatile sources among Earth's building blocks.
  • Naoki Shirai, Motoo Ito, Akira Yamaguchi, Naotaka Tomioka, Masayuki Uesugi, Naoya Imae, Makoto Kimura, Richard Greenwood, Ming-Chang Liu, Takuji Ohigashi, Shun Sekimoto, Kentaro Uesugi, Aiko Nakato, Kasumi Yogata, Hayato Yuzawa, Yu Kodama, Kaori Hirahara, Ikuya Sakurai, Ikuo Okada, Yuzuru Karouji, Satoru Nakazawa, Tatsuaki Okada, Satoshi Tanaka, Takanao Saiki, Fuyuto Terui, Makoto Yoshikawa, Akiko Miyazaki, Masahiro Nishimura, Toru Yada, Masanao Abe, Tomohiro Usui, Sei-ichiro Watanabe, Yuichi Tsuda
    2024年4月4日  
  • Ryoji Tanaka, Dilan M. Ratnayake, Tsutomu Ota, Noah Miklusicak, Tak Kunihiro, Christian Potiszil, Chie Sakaguchi, Katsura Kobayashi, Hiroshi Kitagawa, Masahiro Yamanaka, Masanao Abe, Akiko Miyazaki, Aiko Nakato, Satoru Nakazawa, Masahiro Nishimura, Tatsuaki Okada, Takanao Saiki, Satoshi Tanaka, Fuyuto Terui, Yuichi Tsuda, Tomohiro Usui, Sei-ichiro Watanabe, Toru Yada, Kasumi Yogata, Makoto Yoshikawa, Eizo Nakamura
    The Astrophysical Journal 965(1) 52-52 2024年4月1日  
    Abstract The analysis of samples returned from the C-type asteroid Ryugu has drastically advanced our knowledge of the evolution of early solar system materials. However, no consensus has been obtained on the chronological data, which is important for understanding the evolution of the asteroid Ryugu. Here, the aqueous alteration age of Ryugu particles was determined by the Mn–Cr method using bulk samples, yielding an age of 4.13 + 0.62/−0.55 Myr after the formation of Ca–Al-rich inclusions (CAI). The age corresponds to 4563.17 + 0.60/−0.67 Myr ago. The higher 55Mn/52Cr, ε 54Cr, and initial ε 53Cr values of the Ryugu samples relative to any carbonaceous chondrite samples implies that its progenitor body formed from the least thermally processed precursors in the outermost region of the protoplanetary disk. Despite accreting at different distances from the Sun, the hydrous asteroids (Ryugu and the parent bodies of CI, CM, CR, and ungrouped C2 meteorites) underwent aqueous alteration during a period of limited duration (3.8 ± 1.8 Myr after CAI). These ages are identical to the crystallization age of the carbonaceous achondirtes NWA 6704/6693 within the error. The ε 54Cr and initial ε 53Cr values of Ryugu and NWA 6704/6693 are also identical, while they show distinct Δ'17O values. This suggests that the precursors that formed the progenitor bodies of Ryugu and NWA 6703/6693 were formed in close proximity and experienced a similar degree of thermal processing in the protosolar nebula. However, the progenitor body of Ryugu was formed by a higher ice/dust ratio, than NWA6703/6693, in the outer region of the protoplanetary disk.

MISC

 493

書籍等出版物

 3

講演・口頭発表等

 2
  • 吉川真, 柳沢俊史, 安部正真, 池永敏憲, 岩城陽大, 岡田達明, 菊地耕一, 黒崎裕久, 黒田信介, 佐伯孝尚, 嶌生有理, 津田雄一, 西山和孝, 三桝裕也, 浦川聖太郎, 奥村真一郎
    第23 回宇宙科学シンポジウム 2023年1月6日
  • 三桝裕也, 田中智, 臼井寛裕, 安部正真, 橘省吾, 佐藤広幸, 佐伯孝尚, 吉川 真, 中澤暁, 津田雄一
    第23 回宇宙科学シンポジウム 2023年1月5日

共同研究・競争的資金等の研究課題

 9