仔细观察火星上与水有关的地质活动
A S McEwen1, C J Hansen, W A Delamere
1Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA. mcewen@lpl.arizona.edu
概括
有证据表明,水改变了火星.
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:
- 火星表面呈现出暗示过去水活动的地形.
- 解释这些特征对于理解火星历史至关重要.
研究的目的:
- 以高空间分辨率调查火星上存在水的证据.
- 重新评估火星表面特征的解释,例如海洋沉积物和活跃的峡谷.
主要方法:
- 在火星侦察轨道器上利用了高分辨率成像科学实验 (HiRISE).
- 分析图像的空间尺度为每像素25至32厘米.
- 在中高度和赤道地区检查了巨石分布和峡谷沉积物.
主要成果:
- 在中高度观察到无处不在的巨石 (高达2米),挑战了以前对细粒度沉积物或雪的解释.
- 在的山坡上 (20-35度) 确定了最近的明亮的峡谷沉积物,与干质浪费相一致.
- 在最近的地质中度峡谷和赤道撞击坑中发现了河流修饰的证据.
结论:
- 古代火星海洋的存在仍然没有得到证实.
- 当前峡谷中的活水并没有得到确定的证据.
- 地质上最近的河流过程改变了火星的峡谷和火山口.
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