火星盖尔火山口的一个古老湖泊的再氧化分层
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.
概括
美国国家航空航天局的好奇号探测器在火星的盖尔坑中发现了可居住的古湖的证据. 这个湖经历了气候变化,后来被液所改变,为火星的可居住性提供了见解.
科学领域:
- 星球科学
- 天体生物学
- 地质学
背景情况:
- 美国宇航局的好奇号火星车于2012年登陆火星, 探索盖尔火山口, 寻找过去生命的迹象.
- 这座火山口含有沉积岩, 对于了解火星古气候至关重要.
- 之前的研究表明盖尔火山口内存在可居住的古湖环境.
研究的目的:
- 调查盖尔火山口的一个古老湖泊的可居住性.
- 分析火星沉积岩中保存的古气候记录.
- 了解古代湖泊环境的地化学条件.
主要方法:
- 来自湖床泥石的地化学和矿物学数据的合成.
- 在好奇号任务的第1300个火星太阳日中收集的数据分析.
- 对氧化剂和溶液度的深度依赖变化的检查.
主要成果:
- 古代湖中的氧化还原分层的证据,用化学梯度表示.
- 古气候代理数据显示从寒冷到温暖的气候条件的过渡.
- 通过盐液识别晚期的地化学变化.
结论:
- 盖尔火山口是一个可居住的古湖,
- 沉积层保存了火星气候变化的记录.
- 盐水后的变化影响了地球化学记录.
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