Organic compounds in asteorid Ryugu and chemical evolution in the solar system

2023 Fiscal Year Final Research Report

• Project/Area Number: 20H00202
• 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: Kyushu University
• Principal Investigator: Naraoka HIroshi 九州大学, 理学研究院, 教授 (20198386)
• Co-Investigator(Kenkyū-buntansha): 濱瀬 健司 九州大学, 薬学研究院, 教授 (10284522)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: 小惑星リュウグウ / サンプルリターン / 炭素質隕石 / 有機化合物 / 化学進化 / アミノ酸

Outline of Final Research Achievements

Asteroid Ryuguu materials and carbonaceous chondrite meteorites were extracted with water and organic solvents. The extracted organic molecules were analyzed using high-sensitivity, high-resolution chromatography and mass spectrometry. As a result, about 20,000 molecular compositions consisting of carbon, hydrogen, nitrogen, oxygen and sulfur were detected. Low-molecular-weight amines, carboxylic acids, amino acids, polycyclic aromatic hydrocarbons, and nitrogen-containing cyclic compounds were identified, and enantiomeric amino acids were present as nearly 1:1 racemic mixtures. These organic compounds are thought to be ejected from the surface of the asteroid by perturbation or impact, and to be transported through the solar system.

Free Research Field

有機宇宙地球化学

Academic Significance and Societal Importance of the Research Achievements

炭素質小惑星の表面上に非常に多くの有機分子が存在することを証明した。地球生命が利用しているアミノ酸や核酸塩基、およびカルボン酸などが存在することは生命誕生に至る化学進化への理解につながる。また、太陽系外惑星における生命存在の可能性についても議論できる。さらに将来、人類が地球外で活動する場合に利用できる有機物資源の分布情報も提供した。