General characteristics of dayside auroras for quiet and disturbed conditions are examined on the basis of Greenland and Spitzbergen TV data. It is our new finding that characteristics of dayside auroras are quite different between the pre- and post-noon sectors. Namely, corona auroras are seen in the pre-noon sector and band auroras are seen in the post-noon sector. During the quiet period, corona auroras are observed at magnetic latitudes higher than 75° in the pre-noon sector. In the post-noon sector, no remarkable auroras are seen around 75° MLAT. On the other hand, during the disturbed period, corona auroras are observed at latitudes lower than 80° MLAT in the pre-noon sector. Periodic bright band auroras appear in the post-noon sector. The comparison between these auroras and particle precipitation is also examined and the source region of dayside auroras is discussed.
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