Geospace systems

点击翻译按钮获取中文摘要

Energy flow around and through the Earth's magnetosphere is mediated by a wide range of processes. Most of the basic relationships are broadly understood, but solar terrestrial space science is still a relatively young field with many open questions. Space physics research will increase our understanding of complex sun-Earth interactions that can have significant effects on space- and ground-based technology. Future progress will involve thousands of scientists and engineers around the world bringing together observations, theory, and modeling to study the solar terrestrial system over a wide range of spatial and temporal scales.******My research focuses on two areas: magnetospheric response to solar wind forcing and proton auroral remote sensing of magnetospheric structure and dynamics.******Coupling between the solar wind and the Earth's magnetosphere is extremely complicated. In general, magnetospheric response depends not only on solar wind plasma parameters, but also on the present state and recent time history of the magnetosphere. My research takes advantage of a relatively simple relationship between solar wind dynamic pressure and magnetic field at geostationary orbit. This connection is well-known and has been examined in numerous event studies. However, I have recently developed new analysis methods to demonstrate that this effect can be detected in many thousands of intervals. The time delay between solar wind forcing and magnetospheric response will depend on satellite location, solar wind parameters, and magnetospheric conditions. Arrival time dispersion minima correspond to optimal model parameters, and using a very large data set allows me to determine dependence on other quantities such as magnetic field configuration. This provides an innovative approach to study many different processes including solar wind orientation, propagation, and magnetospheric asymmetry.******Energization and scattering processes in the magnetosphere produce several different types of particle precipitation into the upper atmosphere. The proton aurora (or hydrogen aurora) is a well-known signature of energetic proton precipitation at the equatorward edge of the auroral oval. The luminous intensity is relatively low, so more sensitive instruments are required than for bright electron aurora. As part of my research in this area I operate a network of meridian scanning photometers in northern Canada. Data from this system are used to determine proton auroral location and brightness. This will provide a unique source of information about magnetospheric structure and dynamics.**