Unveiling life-building materials on the early-Earth by analyzing organic materials in Antarctic micrometeorites

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K03830
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 17050:Biogeosciences-related
• Research Institution: Japan Aerospace EXploration Agency
• Principal Investigator: Yada Toru 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, 主任研究開発員 (00294877)
• Co-Investigator(Kenkyū-buntansha): 奈良岡 浩 九州大学, 理学研究院, 教授 (20198386)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 生命材料物質 / 原始地球 / 微隕石 / 氷昇華システム / DESI-Orbitrap MS / 顕微FT-IR / レーザーラマン分光

Outline of Final Research Achievements

We established a new method to extract micrometeorites (MMs), which are estimated to be possible sources of life-building materials in the ancient Earth, without exposing to liquid water and analyze their soluble organic matters. Using this method, we found four MMs candidates from 3kg of Antarctic ice and snow and analyze their soluble and insoluble organic matters. As a result, they should have experienced relatively high temperature compared to carbonaceous chondrites like Murchison, indicating heating during their atmospheric entry. However, we could not identify any indigenous soluble organic matter from them, probably due to eluviation of soluble organic matters caused by deliquescence of attached aerosols during residence in snow and/or ice, or laboratory environment.

Free Research Field

惑星物質科学

Academic Significance and Societal Importance of the Research Achievements

本研究により、原始地球の生命材料物質の供給源と目される微隕石から可溶性有機物を損なわずに分離し、その分析を行う事で、原始地球の前駆生命環境を明らかにする為の研究手法を確立した。残念ながら、今回の研究ではその解明までは到らなかったが、今回確立した手法を用い、更に問題となったエアロゾルの潮解による可溶性有機物の溶脱への対処手法を開発し、更に多くの南極雪氷からの微粒子の分離・微隕石候補粒子の分析を継続する事により、今後、原始地球の前駆生命環境を明らかにされる事が期待される。