The way the magnetic field of the earth connects with the interplanetary magnetic field is an interesting and important problem for understanding the near-earth space environment. Field lines from the polar cap do not close at the opposite pole of the earth when they emanate from higher magnetic latitudes than a boundary called the separatrix, but rather connect with the interplanetary field. Flow of mass and energy across this boundary gives mass and energy flow between open and closed field lines, and drives the majority of magnetospheric processes. The energy involved comes almost entirely from the solar wind. This project seeks to initiate a large-scale study of an important related phenomenon called the magnetospheric reconnection rate under a variety of geophysical conditions using ionospheric observations from the Sonderstrom incoherent scatter radar. The investigators have developed a technique that shows great promise of allowing the measurement of plasma flow across the separatrix, and from this flow to determine the reconnection rate.
