火星の表面で結合された酸化鉄と硫酸塩
J-P Bibring1, R E Arvidson, A Gendrin
1Institut d'Astrophysique Spatiale, Batiment 121, 91405 Orsay Campus, France. bibring@ias.fr
Science (New York, N.Y.)
|August 4, 2007
まとめ
火星 火星 火星 火星
科学分野:
- 惑星科学は惑星科学である.
- 天体生物学 アストロバイオロジー
- 地質学 地質学 地質学
背景:
- 火星探査ローバー (MER) オポチュニティ (Opportunity) は,メリディアン・プランウム (Meridiani Planum) で層状の硫酸塩鉱床を特定しました.
- これらの堆積物は,酸性地下水の上昇期間中に形成されたことを示唆しています.
研究 の 目的:
- 火星の水晶性ヘマタイト堆積物の広範な発生を調査するために.
- メリディアニ・プランウムの水系が,より広範な火星の条件を代表しているかどうかを判断する.
主な方法:
- マース・エクスプレス・オブザーバトリー・フォー・ラ・ミネラロジー・ル・ウォーター・ル・アイスズ・エット・アクティビティ (OMEGA) の軌道データ分析.
- 結晶性ヘマタイトの発生と層状の硫酸塩堆積物の相関.
主要な成果:
- 結晶性ヘマタイトの堆積物は,地理的に火星の複数の場所の硫酸塩の層と関連しています.
- この関連は,広範囲にわたる水性変異過程を示しています.
結論:
- メリディアニ・プランウムに似た酸性地下水系は,火星全体に広範囲に存在していた可能性が高い.
- これらの発見は,火星の過去において,硫酸酸塩酸水系が広く存在していたという仮説を裏付けている.
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