火星の土壌の反応性は,超酸化物イオンによるものであるという証拠
1Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA. Albert.Yen@jpl.nasa.gov
Science (New York, N.Y.)
|September 16, 2000
まとめ
火星の土壌は,紫外線で鉱物表面に形成されるスーパーオキシードラジカルイオンによる化学反応性があります. これは,バイキングの着陸機によって検出された有機物質の欠如を説明します.
科学分野:
- 天体生物学 アストロバイオロジー
- 惑星科学は惑星科学である.
- 地質化学 地質化学
背景:
- バイキングの着陸機は,生命ではなく,有機分子を分解する,反応性のある火星の土壌を検出しました.
- 反応性は,未知の無機超酸化物または過酸化物から生じるという仮説が立てられた.
- 表面有機物質の欠如は未だに説明がつかない.
研究 の 目的:
- 火星の土壌の反応性の源を調査する.
- スーパーオキシドラジカルイオンが火星の鉱物で形成されるかどうかを判断するために.
- バイキングが観察した有機分子分解を説明するために.
主な方法:
- 電子パラ磁気共振スペクトロスコーピーを利用しました.
- 火星のアナログの鉱物表面を,火星の大気条件のシミュレーションに晒した.
- 紫外線で放射された鉱物表面.
主要な成果:
- スーパーオキシードラジカルイオン (O2-) が鉱物表面で形成されるのが直接観察されました.
- 形成は,シミュレートされた火星の大気条件と紫外線被曝下で発生しました.
- これらのラジカルは,土壌の反応性のメカニズムを示しています.
結論:
- スーパーオキシードラジカルイオンは,火星の土壌の反応性の原因である可能性が高い.
- これらのラジカルの存在は,有機分子の分解を説明する.
- この発見は,バイキングランダーの結果に対する化学的な説明を提供する.
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