一个强大的,高度倾斜的星际磁场,靠近太阳系
M Opher1, F Alouani Bibi, G Toth
1George Mason University, 4400 University Drive, Fairfax, Virginia 22030, USA. mopher@gmu.edu
Nature
|December 25, 2009
概括
新的测量显示,当地的星际磁场比以前认为的更强 (3.7-5.5微G),更倾斜. 这一发现影响了我们对日球和银河系磁场的理解.
科学领域:
- 天体物理学 天体物理学
- 等离子体物理学的物理学
- 太空物理学 太空物理学
背景情况:
- 在日球附近的局部星际介质 (ISM) 中磁场的强度和方向对于理解银河系进化至关重要,但受到很少的约束.
- 以前对ISM磁场强度 (1.8-2.5微G) 和方向的估计是基于间接方法,并没有完全考虑星际中性.
研究的目的:
- 为了确定靠近日球的星际介质中磁场的强度和方向.
- 改进日球与当地的ISM相互作用的模型.
主要方法:
- 测量太阳风等离子体流在日光的偏移.
- 利用太空飞船在日球内的观测数据.
主要成果:
- 据估计,当地的ISM磁场强度在3.7至5.5微G之间.
- 磁场与星际介质流动方向倾斜大约20-30度.
- 该场面与银河系平面相比,面向大约30度.
结论:
- 太阳附近的星际磁场明显比以前估计的要强.
- 该场的方向表明它可能在日球附近乱或扭曲.
- 这些发现需要对日球模型及其与当地银河系环境的相互作用进行修订.
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