Large-scale structure of Earth's magnetosphere

地球磁场在太阳风中形成一个空腔，称为磁层;太阳风和磁层之间的相互作用最终决定了近地空间的动态，包括辐射带强度的变化和最壮观的极光（北方和南方极光）。这些相互作用的性质取决于与太阳风有关的磁场（行星际磁场，或IMF）的方向; IMF的“南”方向（与地球磁场相反）对许多磁层过程来说是优先的，但IMF方向变化很大，相比之下，人们对IMF北向条件下的磁层动态知之甚少。鉴于即将开展的欧洲/中国联合使命SMILE（太阳风磁层电离层链路探测器，预计将于2025年发射），对磁层的大尺度结构和动力学进行研究非常及时。该项目将综合利用天基观测（例如，星团、THEMIS和ARTEMIS飞行任务的现场等离子体观测）和地面观测（来自SuperDARN联合体和欧洲非相干散射雷达等电离层雷达），对磁层的大尺度结构进行调查。可能的主题包括：磁层“尖点”的空间范围及其如何取决于太阳风条件;与向北IMF条件有关的磁层结构;和（或）将太阳风与磁层耦合的时变磁重联的性质。

The Earth's magnetic field forms a cavity in the solar wind called the magnetosphere; the interaction between the solar wind and the magnetosphere is ultimately responsible for the dynamics of near-Earth space, including variations in the intensity of the radiation belts and the most spectacular displays of the aurora (the northern and southern lights). The nature of these interactions depends on the orientation of the magnetic field associated with the solar wind (the interplanetary magnetic field, or IMF); a "southward" orientation of the IMF (opposite to the Earth's magnetic field) is preferential for many magnetospheric processes, but the IMF direction is highly variable, and the dynamics of the magnetosphere under northward IMF conditions are, in comparison, poorly understood. Study of the large-scale structure and dynamics of the magnetosphere is highly timely, given the upcoming joint European/Chinese mission SMILE (Solar wind Magnetosphere Ionospheric Link Explorer, expected to launch in 2025). This project will use a combination of space-based observations (e.g. in situ plasma observations from the Cluster, THEMIS and ARTEMIS missions) and ground-based observations (from ionospheric radars such as the SuperDARN consortium and the European Incoherent Scatter radar, EISCAT) to investigate the large-scale structure of the magnetosphere. Possible topics include: the spatial extent of the magnetospheric "cusps", and how that may depend on solar wind conditions; magnetospheric structure associated with northward IMF conditions; and/or the nature of time-varying magnetic reconnection, which couples the solar wind to the magnetosphere.