强大的海洋潮流和外行星卫星上的升温
1Applied Physics Laboratory and Department of Earth and Space Sciences, University of Washington, 1013 NE 40th Street, Seattle, Washington 98105, USA. tyler@apl.washington.edu
Nature
|December 17, 2008
概括
像欧罗巴这样的冰冷卫星上的液态海洋可能被共振罗斯比波加热. 由于轴向倾斜,以前没有考虑的潮力可以驱动这些波浪,提供一个重要的内部热源.
科学领域:
- 行星科学 行星科学
- 海洋学 海洋学 海洋学
- 地质物理学 地质物理学
背景情况:
- 有证据表明,外部行星的卫星上存在液态海洋,特别是欧洲.
- 维持这些地下海洋免受极端寒冷和低辐射热的机制尚未完全理解.
- 当前的理论提出了月球的潮曲和隔热冰层作为主要的热量保留方法.
研究的目的:
- 为了研究加热地下海洋的替代机制在冰冷的卫星上.
- 为了探索潮力量的作用,超越简单的轨道偏心.
- 为了确定这些海洋中的潜在共振现象.
主要方法:
- 在液态海洋中对潮消散的分析.
- 模拟由斜率 (轴倾斜) 引起的潮力.
- 对大振幅罗斯比波的共振激发的研究.
主要成果:
- 在液态海洋中发生强烈的潮消散和加热.
- 由于斜率的潮力可以在共振上激发大振幅的罗斯比波.
- 在欧罗巴,这种共振产生的动能大大大超过主导的潮力.
结论:
- 斜率驱动的潮力量是地下海洋的可信的初级热源.
- 响应罗斯比波为冰雪月球上保持液态水提供了可行的解释.
- 这种机制可能对海洋世界的可居住性评估至关重要.
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