From Earth’s Magnetospheres to the Outer Heliosphere & Beyond
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摘要:在太阳系中,地球、水星、木星、土星、天王星和海王星以及多颗行星的卫星,拥有由太阳风与这些天体的内在磁场相互作用形成的磁层结构。主要根据现有的探测器得到的数据,介绍了太阳风与星际介质的相互作用、能量中性原子分布和拾起粒子相对空间密度变情况、异常宇宙线的形成机制、日球层可能的形状变化。给出了中国太阳系边际探测计划,设计两个相反方向的探测器,一个向日球层鼻尖方向飞行,对太阳系边际及其邻近空间开展全面的探测;另一个探测器向相反方向飞行,填补日球层尾部边界探测的空白。对日球层的空间环境的认识可为探测器的设计提供参考。Abstract:In the Solar system, there are many astronomical objects owning the magnetosphere structure generated by the interaction between their intrinsic magnetic field and Solar wind, including Mercury, Earth, Jupiter, Saturn, Uranus, Neptune and some of their satellites. Heliosphere is the Sun’s magnetosphere, which is filled with Solar wind and surrounded by the interstellar medium. According to the data obtained by the existing detectors, the interaction between the Solar wind and the interstellar medium, the distribution of energy neutral atoms and the relative spatial density changes of picked-up particles, the formation mechanism of abnormal cosmic rays, and possible changes in the shape of the heliosphere are introduced. The marginal exploration plan of China’s Solar system exploration mission is given. Two detectors in opposite directions are designed. One will fly towards the nose tip of the heliosphere to conduct comprehensive exploration of the marginal Solar system and its adjacent space; and the other will fly in the opposite direction to fill the gap at the tail boundary of the spherical layer. The knowledge of the space environment of the heliosphere can provide reference for the design of the probe.Highlights
● The physical processes and spacecraft missions related to heliosphere are reviewed. ● The recent progresses and major questions in the heliophysics are illustrated in terms of energetic neutral ions,pickup ions and anomalous cosmic rays. ● The Interstellar Heliospheric Probes and its main scientific objectives are outlined. -
图 5Voyager 1经过终止激波时观测到异常宇宙线氦离子能谱变化情况
注:在上游[Δ(2004/313-350)]和下游[○(2004/352-2005/052)、x(2005/053-104)、●(2005/105-156)]观测到的异常宇宙线氦离子能谱。在终止激波处,异常宇宙线氦离子通量没有出现峰值,反而在日球层鞘中低能部分通量迅速增加[6]。
Fig. 5Helium spectra of ACR around termination shock observed by Voyager 1
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