Conjugacies of pulsating auroras by all-sky TV observations

Simultaneous observations of pulsating auroras were carried out in September, 1984, using all‐sky TV cameras at a geomagnetically conjugate pair of stations: Syowa Station in Antarctica and Husafell in Iceland. From the data obtained at the two places on 26 September, the following characteristics are found: Spatial configuration of pulsating auroras is very similar in the conjugate regions. In this particular event each pulsating aurora has its counterpart with topologically the same shape in the other hemisphere. However, the timing of the appearance or fade‐out of the pulsating auroras depends on the type of aurora. That is, the patchy type of aurora appears nearly simultaneously in both hemispheres, but the expansion type of pulsating aurora, extending from an aurora with much slower variations, is not synchronously observed and often appears almost out of phase between the conjugate regions.