火星エクスプレス高解像度ステレオカメラからの証拠は,火星の赤道付近の凍った海の証拠です
John B Murray1, Jan-Peter Muller, Gerhard Neukum
1Department of Earth Sciences, The Open University, Milton Keynes MK7 6AA, UK. J.B.Murray@open.ac.uk
Nature
|March 18, 2005
まとめ
証拠によると,火星のエリシウムには,凍った大きな湖があり,おそらくパック氷があることが示唆されています. この500万年前の水域は,古代火星の生命の痕跡を保持している可能性がある.
科学分野:
- 惑星科学は惑星科学である.
- 地質学 地質学 地質学
- 天体生物学 アストロバイオロジー
背景:
- 火星のセルベラス・フォッサエの裂け目が,過去の溶岩と水の洪水源であると推測されている.
- エリシウムの東部には溶岩平原の証拠があるが,関連する水体は蒸発したと考えられていた.
研究 の 目的:
- 火星に存在する水体の可能性を調査するために,Cerberus Fossaeと関連している.
- 高解像度ステレオカメラの画像を分析して,過去の水活動を示す証拠を探します.
主な方法:
- 火星エクスプレス宇宙船からの高解像度ステレオカメラ (HRSC) 画像の分析.
- 地質学的特徴の年齢を決定するためにクレーターカウント.
主要な成果:
- エリシウム南部の約800×900kmの凍った湖の可能性を特定した.
- この特徴は,凍った水体の特徴と一致する特徴を示しており,表面パック氷がある可能性があります.
- クレーター数によると,その特徴の年齢は500万年+/-200万年である.
結論:
- この発見は,火星で大きな水体が凍った状態でまだ存在している可能性を示唆しています.
- この場所は,潜在的原始的な火星生命の証拠を保存するための主要な候補を表しています.
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