太阳和日球在太阳最大值时
E J Smith1, R G Marsden, A Balogh
1Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
Science (New York, N.Y.)
|November 15, 2003
概括
乌利塞斯号数据显示,太阳的磁场几乎垂直于它的旋转轴. 这影响着日球,在全球范围内引导太阳风和粒子,并减少所有度的宇宙射线.
科学领域:
- 空间物理 空间物理
- 太空物理学 太空物理学
- 太阳物理 太阳物理
背景情况:
- 日球的结构和动态对于理解太空天气至关重要.
- 太阳最大值为观测太阳及其扩展环境提供了独特的条件.
- 以前的日球磁场方向模型是基于有限的观测.
研究的目的:
- 描述太阳最大值期间的三维日球.
- 为了研究日球磁场的起源和方向.
- 了解太阳风,能量粒子和宇宙射线的度分布.
主要方法:
- 利用来自乌利塞斯航天器的数据.
- 分析从赤道到极点的广泛太阳度范围内的观测结果.
- 将磁场测量与太阳风特性和能量粒子数据相关联.
主要成果:
- 日球磁场双极的方向几乎垂直于太阳的旋转轴.
- 低度磁场,太阳风和能量粒子传播到所有日球度.
- 在所有度范围内观察到宇宙射线流的对称减少.
- 快速的高度太阳风和极地冠状孔同时消失和重新出现.
结论:
- 太阳的磁场几何学显著影响全球的日球状况.
- 低度现象在填充整个日球层中发挥着主导作用.
- 了解这些动态是预测太空天气事件及其影响的关键.
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