A simultaneous observation of an auroral spiral and its generator region inthe near-Earth plasma sheet is rather unlikely. Here we present such observationsusing the THEMIS spacecraft as well as the THEMIS groundnetwork of all-sky imagers and magnetometers. Two consecutive auroralspirals separated by approximately 14 min occurred during a substorm on 19February 2008. The spirals formed during the expansion phase and asubsequent intensification, and were among the brightest features in theaurora with diameters of 200–300 km. The duration for the formation anddecay of each spiral was less than 60 s. Both spirals occurred shortly afterthe formation of two oppositely rotating plasma flow vortices in space,which were also accompanied by dipolarizations and ion injections, at ~11 geocentric distance. Observations and model calculationsalso give evidence for a magnetic-field-aligned current generation of approximately 0.1 MA via theflow vortices, connecting the generator region of the spirals with theionosphere, during the formation of both spirals. In the ionosphere, a pairof equivalent ionospheric current (EIC) vortices with opposite rotations(corresponding to upward and downward currents) was present duringboth auroral spirals with enhanced EICs and ionospheric flows at thelocations of the auroral spirals and along the auroral arcs. The combinedground and space observations suggest that each auroralspiral was powered by two oppositely rotating plasma flow vortices that caused a current enhancement in the substormcurrent wedge.
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