アポロ15号からの月面サンプルにおける原始放射性元素と宇宙原発放射性核酸
まとめ
バサルトと土壌を含むアポロ15号の月面サンプルを,原始的および宇宙的放射性核素について分析した. 結果は,メアベースタルトとKREEPの混合物であり,すべての標本に対して表面サンプルを採取したことを示しています.
科学分野:
- 地質化学 地質化学
- 核科学は,核科学である.
- 月科学 月科学 月科学
背景:
- アポロ15号は月面から様々なサンプルを回収した.
- アポロ12号のベースアルトの以前の分析は,比較データを提供しています.
研究 の 目的:
- アポロ15号のベースルト,ブレキア,土壌における元素と放射性核酸の濃度を分析した.
- 月面の土壌とブレクチアの組成を決定する.
- 表面サンプリングの影響と宇宙線生成率を調査する.
主な方法:
- 非破壊的なガンマ線スペクトロメトリがサンプル分析に使用されました.
- 分析は,原始放射性元素 (K,Th,U) と宇宙原発放射性核酸に焦点を当てた.
主要な成果:
- アポロ15号の玄武岩に含まれるカリウム,トリウム,ウランの濃度は,アポロ12号の玄武岩に似ているが,K:U比が高い.
- 土壌とブレクシアは,原始放射性元素の濃度を示しており,これはメアベースタルトと最大20%のKREEPの混合物を示唆しています.
- 宇宙的放射性核酸のパターンは,すべての分析された標本の表面サンプル採取を示しています.
- バナジウム-48の生産速度が決定されました.
- コバルト-56濃度は,1971年1月25日の太陽フレアの強さの推定値を提供した.
結論:
- アポロ15号の土壌とブレクシアは,おそらくメアベースルトとKREEPの混合物である.
- 分析されたサンプルはすべて,月面から採取された可能性が高い.
- この研究では,特定の放射性核素の生産速度を定量化し,太陽フレアの強度を推定しました.
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