火星のゲールクレーターにある古代の湖のレドックス層化
J A Hurowitz1, J P Grotzinger2, W W Fischer2
1Department of Geosciences, Stony Brook University, Stony Brook, NY 11794-2100, USA. joel.hurowitz@stonybrook.edu.
まとめ
NASAの探査機"キュリオシティ"は 火星のゲールクレーターで 居住可能な古代湖の証拠を発見しました この湖は気候の変化を体験し,その後塩素流体によって変化し,火星の居住可能性についての洞察を提供しました.
科学分野:
- 惑星科学
- 天体生物学
- 地質学
背景:
- NASAのキュリオシティローバーは 2012年に火星に着陸し ゲールクレーターで 過去の生命の兆候を探しました
- このクレーターには火星の古気候を理解するために 重要な堆積岩が含まれています
- 以前の研究では ゲールクレーターの中に 居住可能な古代の湖環境が 存在していたと示唆されていました
研究 の 目的:
- ゲイルクレーターにある 古代の湖の居住可能性を調べるためだ
- 火星の堆積岩に保存された 古代気候記録を分析するために
- 古代の湖環境の地化学的条件を理解するために
主な方法:
- 湖床の泥岩からの地化学的および鉱物学的データの合成.
- キュリオシティのミッションの 最初の1300日間で 収集されたデータを分析したものです
- 酸化物質と溶液の濃度の深さによる変動の検討
主要な成果:
- 古代の湖の酸化還元分層の証拠は 化学的梯度によって示されています
- 寒い気候から暖かい気候への移行を明らかにする古気候のプロキシデータ.
- 塩溶液による後期地質化学的変化の特定
結論:
- ゲールクレーターには 複雑な酸化再帰条件を持つ 居住可能な古代の湖があった
- 堆積層は火星の 気候変化の記録を保存しています
- 塩溶液による湖後の変化が地化学記録に影響した.
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