Collaborative Research: Inner-Magnetospheric Array for Geospace Science: iMAGS

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This project will combine efforts from three previous projects involving observations of Earth's magnetic field. It will collect data from the AMBER, MEASURE and SAMBA magnetometer arrays and process the data in a uniform manner. The data will be used in several different research projects. One of the major projects will be to improve our understanding of the structure and dynamics of the plasmasphere, including the mass density within the plasmasphere and the location of the plasmapause. The other major research project is to understand how ultra-low frequency (ULF) waves propagate from high to low latitudes and how these waves affect the structure of the equatorial electrojet. Such wave activity may play an important role in the formation of plasma bubbles in the electrojet which then cause strong radio-wave scintillations. Radio-wave scintillations are an important space weather phenomenon that can affect radio communications and GPS location services. In addition to the fundamental research to be carried out by the members of the project, the data from the instruments will be made available to other scientific researchers through a simple web portal. The project will also include education and public outreach activities that involve middle and high school teachers and students. Teachers and students will use the data to enhance public understanding of Earth's space environment.There are two main scientific goals of this program. The first goal is to understand the structure and dynamics of the plasmasphere. To examine that topic the project will make use of resonant oscillations of ULF waves in the plasmasphere. The resonant waves allow one to determine the mass loading along the magnetic field lines that pass through the locations of the magnetometers. The field-line resonance data can also be used to identify the location of the plasmapause (or more accurately, the location of the plasmasphere boundary layer). The PBL can commonly be located on the dayside because ULF wave activity is a common phenomenon on the dayside. In order to locate the PBL on the nightside, the project will utilize TEC (total electron content) data from GPS measurements. The second major scientific goal of the project is to investigate the dynamics of the equatorial electrojet, including the affects of ULF waves and the formation of large plasma irregularities that lead to radio scintillation effects. Radio scintillations at low and equatorial latitudes can have significant effects on radio communications and GPS location accuracy. Indeed, when strong radio scintillation occurs, GPS receives may fail to work at all. This project will examine the longitudinal variability of density irregularities and scintillation. It will also determine how often and under what solar wind conditions ULF waves can propagate from high latitudes to low and equatorial latitudes.