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Published on: February 12, 2013
证明欧罗巴的非同步旋转的证据. 利略的成像团队
P E Geissler1, R Greenberg, G Hoppa
1Lunar and Planetary Laboratory, University of Arizona, Tucson 85712, USA. geissler@pirl.lpl.arizona.edu
Nature
|February 5, 1998
概括
欧罗巴的旋转速度可能比同步旋转速度快,这表明地表下有海洋. 表面特征的分析支持这种非同步旋转,可能使表面与欧罗巴内部脱.
科学领域:
- 行星科学 行星科学
- 天体物理学 天体物理学
- 地质物理学 地质物理学
背景情况:
- 理论模型预测了欧罗巴由于木星的潮力和轨道偏心而发生非同步旋转.
- 潜在的内部质量不对称可能会抵消潮扭矩,如果观察到非同步旋转,就意味着表面脱.
研究的目的:
- 使用利略航天器数据分析欧罗巴的表面特征.
- 调查非同步旋转的证据及其对地下海洋的影响.
主要方法:
- 分析欧洲的全球线条和赤道裂纹的方向和分布.
- 利用利略航天器的初步观测结果.
主要成果:
- 有证据表明,欧罗巴的旋转速度比同步速度快,或者在历史上是这样做的.
- 观察到的表面特征与非同步旋转一致.
结论:
- 非同步旋转支持欧洲上有一个全球地下海洋的假设.
- 这些发现表明,欧罗巴的表面和内部之间存在脱.
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