Field-aligned currents between 400 and 3000 km in auroral and polar latitudes

The polar orbiting magnetically stabilized satellite AZUR measured transverse magnetic variations in auroral and polar latitudes by means of a two component flux-gate magnetometer. Simultaneous measurements of $\text{λ2972}\text{A}\text{?}$ and $\text{λ3914}\text{A}\text{?}$ auroral emissions are related to low-energy zero-pitch-angle electron fluxes, which cause the transverse magnetic disturbances. Power spectra of the magnetic field variations are consistent with those of geomagnetic micropulsations.The sources of the field-aligned currents can be located in the Alfvén layer and in the magnetotail.