在Callisto的一个内部液态水海洋的抗稳定性
1Departamento de Geodinámica, Facultad de Ciencias Geológicas, and Seminar on Planetary Sciences, Universidad Complutense de Madrid, Spain. jaruiz@eucmax.sim.ucm.es
Nature
|July 27, 2001
概括
卡利斯托·卡利斯托 (Callisto) 是一个
科学领域:
- 行星科学 行星科学
- 地质物理学 地质物理学
- 天体生物学 天体生物学
背景情况:
- 木星的卫星卡利斯托的诱导磁场表明有一个地下海洋.
- 现有的模型很难解释由于潮加热不足而导致的海洋生存.
- 以前的研究表明,冰的不稳定性导致海洋结.
研究的目的:
- 重新评估卡利斯托冰的稳定性.
- 调查潜在的地下海洋的长期生存情况.
- 结合现实的冰粘度模型.
主要方法:
- 应用了压力依赖的非牛顿式冰粘度模型.
- 分析了外层冰对固态对流的稳定性.
- 将结果与使用牛顿粘度的先前模型进行比较.
主要成果:
- 外部冰是稳定的对抗对流与现实的粘度.
- 这种稳定性允许地下海洋的长期生存.
- 消除了对抗或不寻常条件的需求,以解释海洋.
结论:
- 鉴于稳定的冰动态,卡利斯托的地下海洋是合理的.
- 现实的冰物理学解决了以前的理论冲突.
- 支持冰雪月球上存在现存液态水的可能性.
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