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根据太阳风的速度调节土星的无线电时钟
Philippe Zarka1, Laurent Lamy, Baptiste Cecconi
1Laboratoire d'Etudes Spatiales et d'Instrumentation en Astrophysique, Observatoire de Paris, Centre National de la Recherche Scientifique, Université Pierre et Marie Curie, Université Paris Diderot, 92190 Meudon, France. philippe.zarka@obspm.fr
Nature
|November 13, 2007
概括
土星的无线电旋转周期不是恒定的. 波动与太阳风的速度有关,这表明外界对地球磁层及其无线电时钟的控制. 这影响了我们对行星旋转的理解.
科学领域:
- 行星科学 行星科学
- 空间物理 空间物理
- 无线电天文学 无线电天文学
背景情况:
- 巨行星的内部旋转速度很难准确地测量.
- 与行星磁场相关的无线电辐射被用作旋转的代理.
- 土星的千米辐射 (SKR) 周期,最初被认为是恒定的,显示了长期的变化.
研究的目的:
- 为了研究土星SKR周期的短期变化.
- 确定影响这些观察到的周期波动的因素.
- 了解土星旋转代理和太阳风条件之间的关系.
主要方法:
- 对土星千米辐射 (SKR) 数据的分析.
- 在SKR周期波动和太阳风参数 (速度,密度,压力,磁场) 之间的相关性分析.
- 在SKR时期的短期和长期变化的比较.
主要成果:
- 土星的SKR周期在20-30天的时间尺度上表现出+/-1%的系统变化.
- 这些短期波动与土星的太阳风速度密切相关.
- 没有发现与太阳风密度,动态压力或磁场强度的相关性.
结论:
- 土星的无线电时钟受到外部条件,特别是太阳风速度的重大影响.
- 这个星球的磁层和相关的无线电辐射是由太阳风调节的.
- 土星旋转周期的长期变化很可能是这些太阳风驱动的短期波动的平均值.
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