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在太阳极小时,太阳风很少或根本没有进入金星的大气层
T L Zhang1, M Delva, W Baumjohann
1Space Research Institute, Austrian Academy of Sciences, A-8042 Graz, Austria. tielong.zhang@oeaw.ac.at
Nature
|November 30, 2007
概括
维纳斯 维纳斯 维纳斯 维纳斯 维纳斯
科学领域:
- 行星科学 行星科学
- 空间物理 空间物理
- 航空学是航空学的.
背景情况:
- 金星缺乏全球磁场,导致太阳风与其大气直接相互作用.
- 诱导磁场提供了部分大气屏蔽,但其在太阳最小值的有效性是未知的.
- 目前对太阳风与金星相互作用的理解是基于太阳最大条件.
研究的目的:
- 为了研究金星在太阳最小值期间诱导磁盾的有效性.
- 为了确定太阳风在太阳活动较低的情况下透到金星大气层的程度.
- 评估太阳风对金星大气演化的贡献.
主要方法:
- 磁场测量数据由金星快递号航天器收集.
- 分析的重点是等离子环境和金星周围的弓冲击位置.
- 数据是在低太阳活动条件下收集的.
主要成果:
- 弓冲击被观察到的位置与磁化离子层的完全偏移相一致.
- 微小的太阳风似乎进入金星的电离层,即使在太阳最小值.
- 诱导的磁场有效地保护大气免受太阳风直接影响.
结论:
- 金星的大气层受到太阳风的保护,即使在太阳最小值期间也是如此.
- 诱导的磁场在保护地球方面发挥着至关重要的作用.
- 直接吸收太阳风对大气演变的贡献是最小的.
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