在E环冰粒中含有盐,这些冰粒来自恩塞拉多斯表面下面的海洋
F Postberg1, S Kempf, J Schmidt
1Institut für Geowissenschaften, Universität Heidelberg, 69120 Heidelberg, Germany. frank.postberg@mpi-hd.mpg.de
Nature
|June 26, 2009
概括
对土星E环颗粒的分析显示,盐含量很高,证实了环卫星的存在.
科学领域:
- 行星科学:研究来自土星卫星恩塞拉多斯的E环粒的组成和起源.
背景情况:
- 土星的卫星恩塞拉多从它的南极呈现出羽毛,表明潜在的地下海洋.
- 这些羽毛是土星E环中的冰颗粒的主要来源.
- 以前的分析表明,羽毛粒中的有机或状成分暗示着核心与水的相互作用.
研究的目的:
- 为了确定恩塞拉多的地下液态水是否今天仍然存在.
- 为了确定E环粒的化学成分,以推断羽毛原产地条件.
主要方法:
- 在现场分析E环冰粒.
- 盐成分的识别和量化,特别是盐.
- 观察到的盐的丰度和推断的pH值与恩塞拉多斯海洋模型的比较.
主要成果:
- 确定了一种富含盐 (0.5-2%质量) 的E环粒种群.
- 盐的组成和推断的基本pH值与预测对恩塞拉多的海洋与其岩石核心相互作用的预测密切匹配.
- 原子在羽毛蒸汽中是不可预期的,这解释了它在光学光谱中缺席的原因.
结论:
- 盐在E环粒中的存在提供了强有力的证据,证明了今天源自恩塞拉多斯的液态水柱的存在.
- 这些颗粒的组成支持了关于恩塞拉多的地下海洋与其岩石核心相互作用的假设.
- 这些发现与目前关于恩塞拉多内部海洋和羽毛生成的模型相一致.
相关概念视频
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