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Synthesis and Reaction Chemistry of Nanosize Monosodium Titanate
Published on: February 23, 2016
泰坦的潮是泰坦的潮
Luciano Iess1, Robert A Jacobson, Marco Ducci
1Dipartimento di Ingegneria Meccanica e Aerospaziale, Università La Sapienza, via Eudossiana 18, 00184 Rome, Italy. luciano.iess@uniroma1.it
Science (New York, N.Y.)
|June 30, 2012
概括
卡西尼号航天器的数据显示,泰坦经历了来自土星的周期性潮压力.
科学领域:
- 行星科学 行星科学
- 天文地质学 天文地质学
- 轨道动力学 轨道动力学
背景情况:
- 泰坦以16天的周期绕土星运行,其轨道偏心率为0.028.8.
- 众所周知,潮力量会影响行星体,导致变形和内部应力.
研究的目的:
- 为了检测和量化土星的卫星泰坦内周期性潮压力的签名.
- 为了研究泰坦的内部结构和组成,基于其对潮力量的反应.
主要方法:
- 分析卡西尼航天器在六次近距离飞行 (2006-2011) 中精确测量加速的分析.
- 从引力场变化中确定泰坦的-2度爱情数 (k(2)).
主要成果:
- 检测到泰坦四极重力的周期性变化,大约是静态值的4%.
- 为2度的爱情数计算了两个独立的值:k(2) = 0.589 ± 0.150和k(2) = 0.637 ± 0.224 (2σ).
结论:
- 泰坦的内部必须在轨道时间尺度上变形,以解释观察到的潮反应.
- 这些发现强烈地表明,泰坦内部存在着一个全球地下海洋.
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