Dynamics of the near-Earth space environment

太空时代的到来标志着历史上最激动人心的技术变革之一。在60多年的时间里，我们已经从一个没有任何人造物体绕地球运行的世界，变成了一个空间基础设施触及我们日常生活并支撑着社会许多关键基础设施的世界。对于等离子体物理学来说，太空时代是一个范式转变。似乎在一夜之间，卫星测量解锁了地球的天然等离子体物理实验室，用一个近距离但膨胀的等离子体系统戏弄了研究人员。随着每一个新传感器的发射，近地空间被证明是一个高度动态的环境，在巨大的空间、时间和能量尺度上相互耦合。再加上空间环境的浩瀚和等离子体（上层大气、磁层、太阳风等）之间相互联系的发现，这个复杂系统的本质在很多层面上都知之甚少。

The dawn of the space age marked one of the most exciting technological transitions in history. In a little over 60 years we have gone from a world where nothing human-made had orbited the Earth to one in which space infrastructure touches our everyday lives and underpins much of society's critical infrastructure. For plasma physics, the space age has been a paradigm shift. Seemingly overnight, satellite measurements unlocked the Earth's natural plasma physics laboratory, teasing researchers with a close, yet expansive plasma system. With each new sensor launched, near-Earth space proved to be a highly dynamic environment coupled across vast spatial, temporal and energy scales. Compounded further by the sheer vastness of the space environment and the discovery of interconnections between plasma regimes (upper atmosphere, magnetosphere, solar wind, etc.), the nature of this complex system is poorly understood on many levels. Within the global space physics research community, my group focuses on the dynamics of the near-Earth high energy (>30keV) electron population with two core themes; (1) energization, transport and loss processes in geospace, and (2) impact on the Earth's ionosphere and our technological systems. High-energy electrons are important within this system since they are not contained in the solar wind and thus entirely energized by the natural plasma processes in near-Earth space. Understanding how this population is created, transported and lost within the system is thus core to understanding the space environment. Once energized they are considered "space weather active" due to their ability to impact technology (and humans) in space, making them of particular interest for space utilization. In this proposal I present my vision for developing remote sensing instrumentation and sensor fusion techniques to probe and untangle plasma processes in this severely under sampled domain. In addressing this challenge, my program will make significant progress in understanding fundamental dynamics in the coupled space environment and ionospheric systems, as well as create new data applications for the growing needs of space utilization industries. Specific goals include understanding how effective different plasma waves are in causing loss to the ionosphere, and under what conditions? and how important are the different plasma waves in terms of their impact on the global budget of high energy electrons in the magnetosphere? Members of my group are also utilizing the multitude of ground based instruments to study key parameter coupling to leading edge space weather prediction models and predicting impacts on technology. Coupled with my instrument development program, the research outlined in this proposal will position my group to leverage new data, conduct new science and provide a pivotal component for studying the high energy electron population, building interpretive models and a path toward new scientific understanding.