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Updated: Jul 12, 2026

11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
まとめ
バイキング1号は,火星の上層大気圏で窒素酸化物 (NO) を検出した. 火星の窒素は,地球の窒素より75%重いので,時間の経過とともに大気圏の脱出が顕著であることを示しています.
科学分野:
- 惑星科学は惑星科学である.
- 大気化学 大気化学
- 天体生物学 アストロバイオロジー
背景:
- 惑星の大気の進化を理解することは,居住性を評価するために極めて重要です.
- バイキングミッションは,火星の大気に関する初期インシットデータを提供した.
研究 の 目的:
- バイキング1中性質質量スペクトロメーターのデータを用いて,火星上層大気の組成を分析する.
- 火星の大気ガスの同位体成分を決定する.
- 火星の大気逃亡の歴史と火星の揮発性物質の豊富さを推論するために.
主な方法:
- 火星の上層大気のインシット分析は,バイキング1エアロシェルに搭載された中性質スペクトロメーターを用いて行われました.
- 窒素,炭素,酸素などの主要な大気元素の同位体比を測定する.
主要な成果:
- 火星の上層大気中の酸化窒素 (NO) の検出.
- 火星の大気中の炭素と酸素の同位体組成は,地球のものと似ている.
- 火星は,地球と比較して,窒素-15 ((15) N) で著しい濃度 (約75%) を示しています.
- 少なくとも2ミリバーの部分圧力に相当する推測された初期窒素の豊富さ.
- (18) Oの濃縮を防ぐために,交換可能な大気圧の少なくとも2バーに相当する必要な初期酸素量 (CO2またはH2Oとして).
結論:
- 火星の大気からの脱出は,より重い窒素同位体の大幅な濃縮につながった.
- 大気中の窒素と酸素の初期の大量量は,火星の初期に存在していた可能性が高い.
- これらの発見は,火星の大気進化と過去の潜在的居住可能性についての洞察を提供します.
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