Electric fields in Earth orbital space
Abstract
We had developed a model of the ground state magnetosphere prior to this report and have suggested that the basic magnetosphere is formed and maintained simply by the interaction of the solar wind with the geomagnetic field. It is known, however, that the magnetosphere responds dynamically to changes in the interplanetary magnetic field (IPMF). Instead of the qualitative reconnection theory (which we believe is basically incorrect), we have examined this response in terms of electromagnetic wave propagation in the interplanetary region. We suggest that the interplanetary plasma (solar wind) is magnetized by the solar magnetic sector structure. Electromagnetic waves of higher frequency can propagate through the solar wind without appreciable attenuation. It is the interaction of these disturbance waves with the magnetosphere that causes the observed magnetospheric response to the IPMF. We have examined quantitatively the propagation of electromagnetic disturbances in the interplanetary region and their interaction with the magnetosphere. Only certain modes propagate and there are further restrictions on the waves at the magnetopause. We show that a southward IPMF produces the most dramatic magnetospheric response in the tail region and a northward IPMF in the polar cusp region. Further work on propagation of these fields within the magnetosphere and on a quantitative examination of their oblique incidence on the magnetopause is suggested. We believe this work will help us to quantitatively understand the magnetosphere's dynamic response to the IPMF and should lead to a quantitative predictive capability for many magnetospheric features.
- Publication:
-
Annual Report
- Pub Date:
- September 1984
- Bibcode:
- 1984mdss.rept.....O
- Keywords:
-
- Earth Magnetosphere;
- Earth Orbits;
- Electric Fields;
- Interplanetary Space;
- Electromagnetic Radiation;
- Geomagnetism;
- Incident Radiation;
- Mapping;
- Plasma Waves;
- Solar Wind;
- Variations;
- Wave Propagation;
- Geophysics