アポロ12号のサンプルの炭素,炭化物,メタンのサンプル
まとめ
アポロ12号の月面探査機には,炭化水素やメタンを含む原産の炭素が含まれています. 月石炭化物の炭素同位体組成は,隕石よりも著しく高く,月石の起源が独特であることを示唆しています.
科学分野:
- 地質化学 地質化学
- 月科学 月科学 月科学
- イソトープ分析とは
背景:
- 月面の揮発性物質の起源と組成を理解することは,月面探査にとって極めて重要です.
- 過去の研究では,月のサンプルから様々な炭素種が特定されましたが,その起源は議論の余地があります.
研究 の 目的:
- アポロ12のサンプル12023の総炭素含量と同位体組成を決定するために,罰金.
- 異なる炭素含有物種,特に炭化物と土着メタンを特定し,定量化する.
- 同位体分析を通じて月の炭化物の起源を調査する.
主な方法:
- 炭素の総含有量に関する元素分析.
- 同位体比質量スペクトロメトリによるデルタ (((13) C分析.
- 炭素種を区別するために,塩化デウテリウムを用いた化学水解.
- 1100°Cの真空ピロリシスで,放出されたガスとその同位体変化を分析する.
主要な成果:
- 総炭素含有量は110μg/gで,デルタ13Cは+12‰でした.
- 炭化物と原産メタンが確認され,それぞれ721μg/gと2μg/gで存在していた.
- Pyrolysisは,炭素一酸化物,二酸化炭素,およびメタンを放出し,同位体多様性は複数の炭素源を示しています.
- 月石炭化物は,気象石炭化物とは異なる14‰の高いデルタ13C値を示した.
結論:
- アポロ12号の罰金には,炭化水素やメタンを含む本土の炭素が含まれています.
- 月の炭化物の高デルタ13Cは,それが月原産か,または非常に分断された隕石成分であることを示唆しています.
- 月面の炭素種の起源を完全に解明するには,さらなる研究が必要である.
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