2003年北部の夏,火星でメタンが大量に放出されました
Michael J Mumma1, Geronimo L Villanueva, Robert E Novak
1NASA Goddard Space Flight Center, Mailstop 690.3, Greenbelt, MD 20771, USA. michael.j.mumma@nasa.gov
まとめ
火星で検出されたメタンの羽根は,地質的または生物学的可能性のある潜在的な源を示唆しています. 推定される放出率は,大規模な地上の炭化水素の浸出に匹敵し,火星でのメタンの有意な活動を示しています.
科学分野:
- 惑星科学 惑星科学
- 天体生物学 アストロバイオロジー
- 大気科学 大気科学
背景:
- 生物は地球上のメタンの大部分を生産し,残りは地化学的プロセスによって生成されます.
- 火星のメタンは,生物学的または地質学的活動を示す可能性があります.
研究 の 目的:
- 火星の大気中のメタンの存在と起源を調査する.
- 火星でメタンと水蒸気を同時に測定する.
主な方法:
- 3つの地上望遠鏡で高分散赤外線スペクトロメーターを使用した.
- 北部の夏の初め/後半 (2003年) と春の赤道 (2006年) の近くで観測を行った.
- 様々な火星の経度間隔で同時にメタンと水蒸気を測定した.
主要な成果:
- メタンは,離散的な地域から発生した延長された羽根で検出されました.
- 北部の真夏には,主要な羽根が約19,000トンのメタンを含んでいた.
- 推定されたメタン源の強度は,大型の陸上の炭化水素の浸出 (>/=0.6 kg/s) と比較可能であった.
結論:
- この発見は,局所的な源から火星に活性メタンが放出されていることを示唆している.
- 観測されたメタンの羽根と源の強さは,火星のメタンの起源のさらなる調査を保証します.
- 火星でのメタンの検出は,天体生物学と惑星のプロセスを理解するための意味を持っています.
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