The harang discontinuity in auroral belt ionospheric currents

Observations are compared to the Harang discontinuity to illustrate the reality and form of the discontinuity near midnight. High latitude magnetic disturbances and auroral displays were not found to be completely identical on any two days. The typical diurnal behavior during the night hours between 60 and 70 deg magnetic latitude was illustrated, using two patterns. Convection, time variablity, and current continuity of the Harang discontinuity are considered.