Journal article
IMF By-Related Cusp Currents Observed from the Ørsted Satellite and from Ground
Orsted is the first satellite to conduct high-precision magnetometer observations from low-altitude noonmidnight orbits passing through the polar cusp regions. Field-aligned currents (FAC) derived from Orsted magnetic field measurements have been combined with ionospheric current patterns inferred from ground-based magnetic observations to define the structure and location of cusp currents and their dependencies on interplanetary magnetic field (IMF) conditions.
Example cases illustrate the close relation between IMF B-gamma-related FAC and horizontal ionospheric currents in the cusp region. Our statistical analysis defines for the noon region the variations in FAC latitude with IMF B-Z. Comparisons with the statistical cusp location indicate that the more equatorward region of IMF B-gamma-while the more B related FAC is located on field lines closing at the dayside poleward FAC are on "open" field lines.
High-energy electron measurements from the satellite confirm this result.
Language: | English |
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Year: | 2001 |
Pages: | 99-102 |
ISSN: | 19448007 and 00948276 |
Types: | Journal article |
DOI: | 10.1029/2000GL012010 |