Material Science of the Solar System in a New Era: Formation and Evolution of Hydrous Asteroids at Different Scales

2023 Fiscal Year Final Research Report

• Project/Area Number: 20H00188
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Medium-sized Section 17:Earth and planetary science and related fields
• Research Institution: Tohoku University
• Principal Investigator: Nakamura Tomoki 東北大学, 理学研究科, 教授 (20260721)
• Co-Investigator(Kenkyū-buntansha): 牛久保 孝行 国立研究開発法人海洋研究開発機構, 超先鋭研究開発部門(高知コア研究所), 主任研究員 (10722837) ; 上椙 真之 公益財団法人高輝度光科学研究センター, 分光推進室, 主幹研究員 (20426521) ; 玄田 英典 東京工業大学, 地球生命研究所, 教授 (90456260) ; 臼井 文彦 神戸大学, 理学研究科, 特命助教 (30720669) ; 三宅 亮 京都大学, 理学研究科, 准教授 (10324609)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: 小惑星 / Ryugu / 炭素質隕石 / Hayabusa2

Outline of Final Research Achievements

Material analyses of asteroid samples recovered by the asteroid probe Hayabusa2 and similar CI carbonaceous meteorites using synchrotron radiation and electron microscopes were conducted to elucidate the formation position of hydrous asteroids, their formation environment, and chemical evolution by water quality metamorphism in the interior of the bodies after formation. The physical properties of the samples were also measured, and the impact destruction process of hydrous asteroids was successfully estimated. The results were compiled and published in many scientific journals including Science.

Free Research Field

惑星物質科学

Academic Significance and Societal Importance of the Research Achievements

小惑星からのリターンサンプルを解析し，C型小惑星の起源や形成進化のプロセスを明らかにした．リュウグウのような小惑星が地球に生命の基礎物質や水をもたらした可能性を高めた．また，日本の探査機が持ち帰った小惑星サンプルを詳細に分析し，科学的価値が高いことを示せたのは社会的意義が高いと考えられる．