Did the Formation of Jupiter Break Up the Primordial Solar Nebula? -An Approach from a Differentiated Meteorite

2023 Fiscal Year Final Research Report

• Project/Area Number: 19H01959
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 17010:Space and planetary sciences-related
• Research Institution: National Institute of Polar Research
• Principal Investigator: Yamaguchi Akira 国立極地研究所, 先端研究推進系, 准教授 (70321560)
• Co-Investigator(Kenkyū-buntansha): 白井 直樹 神奈川大学, 理学部, 准教授 (00599805) ; 岡崎 隆司 九州大学, 理学研究院, 准教授 (40372750) ; 飯塚 毅 東京大学, 大学院理学系研究科(理学部), 准教授 (70614569)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Keywords: 隕石 / エコンドライト / 原始惑星 / 熱履歴

Outline of Final Research Achievements

We studied petrology, geochemistry, and chronology of differentiated achondrites to elucidate the evolutionary process of differentiated proto-planets. Achondrites such as basaltic and andesitic meteorites derived from the inner Solar System and the NWA 011 meteorite, known as the outer solar system origin, were analyzed. We found that these meteorites experienced similar secondary processes, such as shock metamorphism, after their formation. EC 002 is an andesitic meteorite formed by partially melting the chondritic source. Severa angrites have heterogeneity of oxygen isotopes, indicating large-scale collisions of differentiated protoplanets shortly after the formation of the Solar System.

Free Research Field

隕石学、鉱物学

Academic Significance and Societal Importance of the Research Achievements

これまで、エコンドライトの元素組成、年代情報、同位体組成、熱史などの情報がばらばらに議論されてきた。特に、熱的イベントの強度や頻度の比較に関する議論は見落とされてきた。本研究では、これらを統合的に議論しようとした。年代、形成位置や形成条件を検討する品質の良いデータを提供することで、理論や数値シミュレーション精度の向上に貢献する。