概括
来自当地的星际云的中性在太阳系中减速.
科学领域:
- 天文学和天体物理学
- 星际介质 星际介质
- 球物理 球物理
背景情况:
- 高分辨率的恒星光谱显示了当地的星际云的吸收线.
- 这个云与太阳相比以26公里/秒的速度移动,与星际风保持一致.
- 以前的测量表明,在太阳系内,中性和的速度不同.
研究的目的:
- 为了研究太阳系内部的局部星际云中中性和的速度.
- 为了确定星际物质与日球界面的相互作用.
- 为了限制星际等离子体的密度和日球冲击的位置.
主要方法:
- 来自附近恒星的高分辨率光谱的分析,以研究星际云物质.
- 利用乌利塞斯航天器的数据进行中性漂移测量.
- 使用哈勃太空望远镜的高分辨率光谱仪进行新的排放线测量.
主要成果:
- 来自当地的星际云的中性以26公里/秒的速度漂移,与星际风相一致.
- 来自同一云的中性气减速到20公里/秒.
- 这种减速归因于在日球界面与星际质子之间的电荷交换.
结论:
- 中性原子最好通过与日球等离子体的相互作用来减速.
- 中性不受等离子体的影响,表明有选择性的相互作用.
- 观察到的减速意味着星际等离子体密度为0.060.10厘米-3,将日球冲击置于距离太阳100AU之内.
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