Tracing geomagnetic conjugate points using exceptionally similar synchronous auroras

Abstract

We report on highly similar auroras that were simultaneously acquired with all-sky TV cameras situated at two geomagnetically conjugate points, at Tjornes in Iceland and at Syowa Station in Antarctica. During this event, meso-scale discrete auroras, including both east-west and north-south directed auroral forms, showed excellent similarity in terms of shapes, movements and luminosity variations at both observatories. Using these data we were able to trace the temporal movements and displacement of auroras in the Northern and Southern Hemispheres with a high spatial-temporal resolution. Our results indicate that the geomagnetic conjugate point of one station moved ∼200 km in longitude and ∼50 km in latitude in one hour due to changes in topology of the geomagnetic field. Similar and dissimilar auroras appeared simultaneously in adjoining areas of sky in both hemispheres. Copyright 2005 by the American Geophysical Union.