在火星磁力异常上方的等离子加速
R Lundin1, D Winningham, S Barabash
1Swedish Institute of Space Physics, Box 812, S-98 128, Kiruna, Sweden.
概括
火星上明亮的极光是由能量粒子在行星夜侧大气中加速引起的. 这些条件类似于地球上的极光,与火星地的磁场有关.
科学领域:
- 行星科学 行星科学
- 空间物理 空间物理
- 大气科学 大气科学
背景情况:
- 极光是由带电粒子撞击行星大气层造成的.
- 极光的亮度与沉粒子的能量流相对应.
- 火星拥有影响其太空环境的地磁场.
研究的目的:
- 为了研究火星夜侧的带电粒子加速过程.
- 为了确定火星极光中沉粒子的能量流.
- 了解火星极光和地磁性之间的关系.
主要方法:
- 在Mars Express航天器上利用了空间等离子体和能量原子分析器实验.
- 分析了火星高海拔夜边区域的加速电子和离子.
- 将粒子加速区域映射到火星地磁化区域.
主要成果:
- 在火星深夜高海拔地区观察到加速的电子和离子.
- 从地理上绘制这些区域的地图,以与地磁化相关的接口/裂区域.
- 测量的能量流量在每平方米每秒1到50毫瓦之间.
结论:
- 火星的离散极光与地磁化区域上方分离的磁流管中的等离子加速有关.
- 火星极光的复杂模式是由多极磁场线形成的.
- 观察到的条件与地球上产生明亮的离散极光的条件相似.
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