硫酸盐和火星上水的历史
David T Vaniman1, David L Bish, Steve J Chipera
1Los Alamos National Laboratory (LANL), MS D462, Los Alamos, New Mexico 87545, USA. vaniman@lanl.gov
Nature
|October 8, 2004
概括
火星上的硫酸盐可以保留大量的水,这可能解释了观察到的赤道水. 它们的水分状态对温度和湿度敏感,需要在现场进行分析,以准确评估火星水史.
科学领域:
- 行星科学 行星科学
- 天体生物学 天体生物学
- 地质化学 地质化学
背景情况:
- 火星表面沉积物约含有30%的硫酸盐,可能是水合的形式.
- 化硫酸盐可能是奥德赛航天器探测到的赤道水.
研究的目的:
- 为了研究在火星表面条件下MgSO4*nH2O (硫酸水合物) 的持水能力.
- 根据温度,压力和湿度来限制这些盐的可能H2O含量.
主要方法:
- 暴露MgSO4*nH2O相在不同的温度,压力和湿度下.
- 分析晶体结构和H2O含量.
- 对无形相脱水的动力学研究.
主要成果:
- 化状态和晶体结构取决于温度-压力历史.
- 在相对湿度低于1%的情况下,形成具有缓慢脱水动力学的无形水合相.
- 硫酸盐可以保留足够的水,以解释一些奥德赛观测.
结论:
- 硫酸水合物可以保留大量的H2O,有助于理解火星水.
- 这些盐对环境条件的敏感性凸显了现场分析的重要性.
- 盐水合物的转化需要在采样时立即进行分析,以保持它们的原始状态.
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