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The Alaskan meridian chain of stations ‘scans’ the polar sky like an azimuth scan radar once a day between the corrected geomagnetic latitudes of 60° and 85°N. The all-sky photographs from the chain of stations have provided and clarified several important features of auroral morphology, in particular the dynamics of the night-sector auroral oval. The main results are in the summary.
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Snyder et al. (1972) studied this question.
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