アポロ12号の月面サンプル:核の微量元素分析とレゴリットの一致性
Science (New York, N.Y.)
|October 30, 1970
まとめ
アポロ12号からの月面土壌サンプルでは,アポロ11号と同じような隕石の微量元素の濃縮が示されている. これは,月の平均的な隕石流入率を確認し,一部のサンプルは極端なビスムートとカドミウム濃縮を示しています.
科学分野:
- 月面地質学 月面地質学
- 宇宙化学 (コスモケミストリー)
- 惑星科学は惑星科学である.
背景:
- アポロ11号のサンプルは,月面の組成に関する最初の洞察を提供した.
- 隕石の流入を理解することは,月の進化モデルにとって極めて重要です.
研究 の 目的:
- アポロ12号の核と土壌サンプルの微量元素の成分を分析するために.
- 月面での隕石流入の速度を測定するために.
- 特定の月面サンプルにおける異常な元素濃縮を調査するために.
主な方法:
- アポロ12ミッションから採取した4つのコアと土壌のサンプルを分析した.
- アポロ11号のデータと微量元素濃度の比較.
- 構成の類似点と違いを特定するための地化学分析.
主要な成果:
- アポロ12号のサンプルは,アポロ11号の土壌に匹敵する微量元素の濃度を示しています.
- 月の隕石の平均流入率は,約4×10−9g/cm2/年である.
- 一つのサンプルでは,ビスムートとカドミウムの非常に高い濃度 (10^4〜10^5倍) が示されました.
結論:
- 隕石の流入率は,異なる月面着陸地点にわたって一貫しています.
- 月は,地球外物質の安定した堆積を経験しています.
- 特定の地質学的プロセスは,ビスムートやカドミウムのような特定の揮発性元素の局所的で極端な濃縮につながる可能性があります.
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