CAREER: Upper Atmospheric Density from Precision Orbit Determination

利用精密的卫星轨道星历数据和卫星激光测距，在小至两小时的时间尺度上测量了热层的绝对总密度和密度波动。高精度数据是从两颗卫星上获取的，这些卫星上有非常精确的加速度计信息，并通过适用于数百颗卫星的最佳轨道确定技术进行的现代卡尔曼滤波分析。准确确定200公里至1400公里之间的大气密度及其时间变化对于验证大气密度模型和准确量化卫星阻力是有用的。利用导出的密度涨落与太阳通量指标和磁指数的相关性，研究了时间和全球密度变化对太阳和地磁强迫的敏感性。这项研究是通过为研究生开设轨道力学和高层大气物理课程而引入课堂的。该课程提供参与远程学习的选项。工程设计项目是为本科生参与研究而开发的，与海龟岩社区学院的正式合作通过研究生助理参与和在该学院的讲座将美洲原住民直接纳入研究计划。

Absolute total density and density fluctuations in the thermosphere, on time scales as small as two hours, are measured using precision satellite orbit ephemeris data and satellite laser ranging. High precision data are retrieved from two satellites with very precise accelerometer information on board, and from modern Kalman filtering analyses within the optimal orbit determination technique applicable to hundreds of satellites. The precise determination of atmospheric density between 200 km and 1400 km and its temporal variation is useful for validation of atmospheric density models and for accurate quantification of satellite drag. Correlation of derived density fluctuations with solar flux proxies and magnetic indices are used to investigate the sensitivity of temporal and global density changes to solar and geomagnetic forcing. The research is brought into the classroom by creation of an orbital mechanics and upper atmospheric physics class for graduate students. That course is offered with the option of distance learning participation. Engineering design projects are developed for undergraduate research participation, and a formal collaboration with the Turtle Rock Community College brings Native Americans directly into the research program through graduate assistant participation and lectures at the College.