Mineralogy and petrology of carbonaceous chondrites and cometary particles: Insights to the evolution of water-bearing asteroids.

• Project/Area Number: 16K05603
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Petrology/Mineralogy/Economic geology
• Research Institution: The Graduate University for Advanced Studies
• Principal Investigator: Komatsu Mutsumi 総合研究大学院大学, 教育開発センター, 助教 (50609732)
• Project Period (FY): 2016-10-21 – 2020-03-31
• Project Status: Completed (Fiscal Year 2019)
• Budget Amount: ¥4,550,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥1,050,000); Fiscal Year 2018: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2017: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2016: ¥2,990,000 (Direct Cost: ¥2,300,000、Indirect Cost: ¥690,000)
• Keywords: 原始太陽系 / 炭素質コンドライト / 水質変成 / 難揮発性包有物 / 小惑星 / 隕石 / 太陽系 / 惑星起源・進化 / 始原隕石 / はやぶさ2

Outline of Final Research Achievements

In order to understand the evolution of primitive C-type asteroids, the detailed formation history of primitive meteorites was examined. We focused on the mineralogy of Renazzo-type carbonaceous (CR) chondrites. CR chondrites are understood as one of the most primitive meteorites; however, because of the rarity of CR chondrites, their parent body is not well understood. Our results show CR chondrites escaped from thermal metamorphism, but the degree of aqueous alteration is highly variable. We also found one amoeboid olivine aggregate (AOA) in one of our samples. It contains minerals with 16O-rich compositions consistent with the nebular setting. The AOA provides direct evidence that silica condensed from gas in a CAI/AOA-forming region in our solar system indicates that gas became Si-rich as Mg condensed and may explain the origin of silica detected from infrared spectroscopy of T Tauri and asymptotic giant branch stars.

Academic Significance and Societal Importance of the Research Achievements

本研究では、原始太陽系での凝縮過程から始原的小惑星の進化を理解するため、始原的隕石の水質変成・加熱履歴を詳細な条件を明らかにすることを目的とした。始原的小惑星は、原始太陽系星雲内の固体物質の形成過程から、始原的小惑星の集積過程と初期の母天体活動を保存する重要な物質である。また、始原的小惑星には水や有機物が多く含まれており、その進化を明らかにすることは、原始地球の海や生命の起源を理解するという意味でも大きな社会的意義を持つ。また本研究は「はやぶさ２」探査とも連携しており、今後「はやぶさ２」探査の帰還試料分析と本研究を発展させることで、原始太陽系での物質進化の詳細が解明されることが期待される。

Research Products

• [Int'l Joint Research] University of Hawaii at Manoa/NASA Johnson Space Center(米国)
• [Int'l Joint Research] University of Hawaii/Harvard University/NASA Johnson Space Center(米国)
• [Int'l Joint Research] NASA Johnson Spance Center/University of Hawaii(米国)
• [Int'l Joint Research] NASA Johnson Space Center/University of Hawaii(米国)
• [Journal Article] First evidence for silica condensation within the solar protoplanetary disk (2018)
  • Author(s): Komatsu Mutsumi、Fagan Timothy J.、Krot Alexander N.、Nagashima Kazuhide、Petaev Michail I.、Kimura Makoto、Yamaguchi Akira
  • Journal Title: Proceedings of the National Academy of Sciences Volume: 115 Issue: 29 Pages: 7497-7502
  • DOI: 10.1073/pnas.1722265115
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] NIRS3: the near infrared spectrometer on Hayabusa2 (2017)
  • Author(s): Iwata, T., Kitazato, K., Abe, M., Ohtake, M., Arai, T., Arai, T., Hirata, N., Hiroi, T., Honda, C., Imae, N., Komatsu, M., Matsunaga, T., Matsuoka, M., Matsuura, S., Nakamura, T., Nakato, A., Nakauchi, Y., Osawa, T., Senshu, H., Takagi, Y., Tsumura, K., Takato, N., Watanabe, S., Barucci, M. A., Palomba, E., Ozaki, M.
  • Journal Title: Space Science Reviews Volume: 印刷中 Issue: 1-4 Pages: 317-337
  • DOI: 10.1007/s11214-017-0341-0
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] An evaluation method of reflectance spectra to be obtained by Hayabusa2 Near-Infrared Spectrometer (NIRS3) based on laboratory measurements of carbonaceous chondrites (2017)
  • Author(s): Matsuoka Moe、Nakamura Tomoki、Osawa Takahito、Iwata Takahiro、Kitazato Kohei、Abe Masanao、Nakauchi Yusuke、Arai Takehiko、Komatsu Mutsumi、Hiroi Takahiro、Imae Naoya、Yamaguchi Akira、Kojima Hideyasu
  • Journal Title: Earth, Planets and Space Volume: 69 Issue: 1 Pages: 120-120
  • DOI: 10.1186/s40623-017-0705-4
  • NAID: 120006472642
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] エポックメイキングな隕石たち その10 Y-81020～極めて始原的な日本の南極産隕石～ (2016)
  • Author(s): 小松睦美
  • Journal Title: 日本惑星科学会誌 Volume: 25 Pages: 8-12
  • NAID: 130005313138
  • Peer Reviewed
• [Presentation] Petrology of Chondrule Rims in Yamato-791498 and Asuka-881828, The Least-altered CR Chondrites in The Japanese NIPR Collection. (2020)
  • Author(s): M. Komatsu, T. J. Fagan, A. Yamaguchi, M. Kimura, M. Yasutake, T. Mikouchi and M. E. Zolensky
  • Organizer: 51st Lunar and Planetary Science Conference
  • Int'l Joint Research
• [Presentation] ULTRA-REFRACTORY CAI IN A LOW-CA PYROXENE- AND SILICA-BEARING AMOEBOID OLIVINE AGGREGATE IN A CR CHONDRITE: FORMATION BY GAS-SOLID CONDENSATION OVER A WIDE TEMPERATURE RANGE. M. Komatsu1,2, T. J. Fagan2, A. N. Krot3, K. Nagashima3, M. I. Petaev4, M. (2019)
  • Author(s): M. Komatsu, T. J. Fagan, A. N. Krot, K. Nagashima, M. I. Petaev, M. Kimura, and A. Yamaguchi
  • Organizer: 82nd Annual Meeting of The Meteoritical Society
  • Int'l Joint Research
• [Presentation] Ryuseito: The Japanese Swords Made from Shirahagi Iron Meteorite. (2019)
  • Author(s): M. Komatsu, A. Yamaguchi, M. Ito, S. Yoneda, T. Saito, T. Ohgane, T. Hayashi, M. Sakamoto, T. Mikouchi.
  • Organizer: 82nd Annual Meeting of The Meteoritical Society
  • Int'l Joint Research
• [Presentation] Y-791498 and A-881828: The least-altered CR chondrites in the NIPR Antarctic meteorite collection. (2019)
  • Author(s): M. Komatsu, T. J. Fagan, A. Yamaguchi, M. Kimura, M. Yasutake, T. Mikouchi, and M. E. Zolensky
  • Organizer: The Tenth Symposium on Polar Science
  • Int'l Joint Research
• [Presentation] Examination of Silica Polymorphs in the CR Chondrites (2019)
  • Author(s): Mutsumi Komatsu
  • Organizer: 50th Lunar and Planetary Science Conference,
  • Int'l Joint Research
• [Presentation] Primary mineralogy and secondary alteration characteristics observed in Antarctic CR chondrites (2018)
  • Author(s): Mutsumi Komatsu
  • Organizer: The Ninth Symposium on Polar Science
  • Int'l Joint Research
• [Presentation] Ulltra-Refractory Ca-Al-rich Inclusion in an AOA in CR Chondrite Y793261. (2017)
  • Author(s): Komatsu M.
  • Organizer: The 48th Lunar and Planetary Science Conference
  • Place of Presentation: Woodlands, TX, USA
  • Year and Date: 2017-03-20
  • Int'l Joint Research
• [Presentation] Petrology of amoeboid olivine aggregates in Antarctic CR chondrites: Evidence for aqueous alteration and shock metamorphism. (2017)
  • Author(s): Mutsumi Komatsu
  • Organizer: The Eighth Symposium on Polar Science
  • Int'l Joint Research
• [Presentation] Amoeboid Olivine Aggregates in Antarctic CR Chondrites: Petrologic Variations Among CR Chondrites (2017)
  • Author(s): Mutsumi Komatsu
  • Organizer: Mutsumi Komatsu
  • Int'l Joint Research
• [Presentation] A Unique Ultra-refractory Inclusion-bearing AOA from Y-793261 (2016)
  • Author(s): Komatsu M.
  • Organizer: The Seventh Symposium for Polar Science
  • Place of Presentation: 東京・立川
  • Year and Date: 2016-11-29
  • Int'l Joint Research