Accession Number:

ADA139277

Title:

Satellite Measurements of Auroral Coupling Processes,

Descriptive Note:

Corporate Author:

AIR FORCE GEOPHYSICS LAB HANSCOM AFB MA

Personal Author(s):

Report Date:

1982-11-01

Pagination or Media Count:

2.0

Abstract:

The high spatial-temporal resolution of instrumentation on the polar orbiting S3-2 satellite has allowed a wide variety of measurements of the electrodynamic characteristics of both large- and small-scale structures at high latitudes. Analyses of large scale features observed by S3-2 have shown that i The IMF B sub y dependence of polar cap convection, first observed in June 1969 by OGO-6 persists in other seasons. During periods of northward IMF B sub z extensive regions of sunward convection may be found in the sunlit polar cap. ii In the dawn and dusk MLT sectors 90 of the Region 1 currents lie equatorward of the convection reversal line. Potentials across the ionospheric projection of the low-latitude boundary layer are typically a few kV. iii The location of extra field-aligned currents, near the dayside cusp and poleward of the Region 1 current sheet is dependent on the IMF B sub y component. iv Simultaneous observations by TRIAD and S3-3 show that sheets of field-aligned current extend uniformly for several hours in MLT, but may have an altitude dependence in the 1000-8000 km range. v During magnetic storms ionospheric irregularities generated by scintillations occur in regions of poleward density gradient and downward field aligned current near the equatorward boundary of diffuse auroral precipitation.

Subject Categories:

  • Atmospheric Physics
  • Spacecraft Trajectories and Reentry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE