日本地球惑星科学連合2015年大会

講演情報

インターナショナルセッション(ポスター発表)

セッション記号 B (地球生命科学) » B-AO 宇宙生物学・生命起源

[B-AO01] Astrobiology: Origins, Evolution, Distribution of Life

2015年5月27日(水) 18:15 〜 19:30 コンベンションホール (2F)

コンビーナ:*小林 憲正(横浜国立大学大学院工学研究院)、山岸 明彦(東京薬科大学生命科学部)、大石 雅寿(国立天文台天文データセンター)、田近 英一(東京大学大学院新領域創成科学研究科複雑理工学専攻)、掛川 武(東北大学大学院理学研究科地学専攻)、井田 茂(東京工業大学大学院理工学研究科地球惑星科学専攻)

18:15 〜 19:30

[BAO01-P03] Exposure experiments of amino acids and their precursors at the exposure facility on ISS

*癸生川 陽子1三田 肇2小林 憲正1橋本 博文3今井 栄一4伊藤 隆哉1金子 竹男1中川 和道5矢野 創3山岸 明彦6Working Group Tanpopo3 (1.横浜国立大学、2.福岡工業大学、3.宇宙航空研究開発機構・宇宙科学研究所、4.長岡技術科学大学、5.神戸大学、6.東京薬科大学)

Since a diverse suite of amino acids is found in carbonaceous chondrites, exogenous delivery of organic matter could have played an important role for the prebiotic chemical evolution on the early Earth. The interplanetary dust particles (IDPs) are considered to be the major carbon source [1]. However, the organic matter in IDPs is susceptible to the cosmic and solar radiation due to their small nature.
The Tanpopo mission consists of capture experiments and exposure experiments of organic matter and microbes at the Exposure Facility of Japan Experimental Module (JEM) "Kibo" on the International Space Station (ISS), which aims to investigate possible interplanetary migrations of organics and microbes. Here we report the exposure experiments of amino acids and their precursor molecules to the space environment to explore their alteration and survivability.
Selected organic compounds are amino acids (glycine and isovaline), their possible precursors (hydantoin and 5-ethyl-5-methyl hydantoin), and a complex amino acid precursor material synthesized from a mixture of carbon monoxide, ammonia and water by proton irradiation (here after called "CAW"). The amino acid water solutions, hydantoin ethanol solutions, and CAW were put into 3 μL pits on the exposure panels, and dried under a clean booth. The solid samples were left on the pits ca. 75 nmol each for amino acids and hydantoins, and 15 nmol equivalent to glycine for CAW. Then the samples were covered with hexatriacontane (C36H74) in order to prevent the sample lost during the experiments and transportations. The exposure panels will be launched in this year, and will be recovered after one year, two years and three years of exposure.

[1] Chyba C. and Sagan C. (1992) Nature, 355, 125-132.