来自Mars Express高分辨率立体声摄像机的证据显示,火星赤道附近的一片冰的海洋
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
概括
有证据表明,在火星的Elysium存在一个大而冰的湖泊,可能含有冰块. 这种潜在的500万年历史的水体可能含有古代火星生命的线索.
科学领域:
- 行星科学 行星科学
- 地质地质地质地质地质地
- 天体生物学 天体生物学
背景情况:
- 火星上的Cerberus Fossae裂是过去岩和水洪水的假设来源.
- 在Elysium东部存在岩平原的证据,但相关的水体被认为已经蒸发了.
研究的目的:
- 为了调查火星上与Cerberus Fossae相关的现存水体的潜力.
- 分析高分辨率立体声摄像头图像,寻找过去水活动的证据.
主要方法:
- 分析来自火星快递航天器的高分辨率立体相机 (HRSC) 图像.
- 计数火山口以确定地质特征的年龄.
主要成果:
- 在伊利西乌斯南部,确定了一个大约800 x 900公里的潜在冰湖.
- 该特征表现出与结水体相一致的特征,可能有表面积冰.
- 石坑的数量表明该特征的年龄为500万年或200万年.
结论:
- 这些发现表明,火星上可能仍然存在大量的水体,处于结状态.
- 这个位置代表了保存潜在的原始火星生命证据的首选候选人.
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