在恩塞拉多斯内部正在进行的热水活动
Hsiang-Wen Hsu1, Frank Postberg2, Yasuhito Sekine3
1Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA.
Nature
|March 13, 2015
概括
对恩塞拉多斯的分析
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:
- 土星的一个卫星恩塞拉多斯 (Enceladus) 呈现出含有冰粒的羽毛.
- 探测到地下海洋,表明潜在的热水活动.
- 以前检测到富含盐的颗粒表明岩石与水的相互作用.
研究的目的:
- 分析来自恩塞拉多星的羽毛中的富含的纳米尘埃粒子 (流粒子).
- 研究这些独特粒子的起源和影响.
- 确定恩塞拉多的地下海洋的条件.
主要方法:
- 对纳米尺寸SiO2 () 颗粒的分析.
- 对粒子组成和大小分布的解释.
- 与太空飞船测量羽毛组成的相关性.
主要成果:
- 识别的流粒子是纳米尺寸的二氧化 (SiO2).
- 确定粒子大小范围 (2-8纳米半径).
- 表示高温 (>90°C) 水热反应.
结论:
- 在恩塞拉多的海底,热水活动正在进行中.
- 全球地热活动将热水产品运送到羽毛.
- 这些发现支持恩塞拉多的地下海洋的潜在可居住性.
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