Координированные наблюдения авроральных явлений 1-2 декабря и 11-12 декабря 1977 г. на Кольском полуострове и в Финляндии / С. А. Черноус, Н. И. Федорова, Г. А. Логинов и др. ; Акад. наук СССР, Кол. фил. им. С. М. Кирова, Поляр. геофиз. ин-т. – Препр. ПГИ-79-3. - Апатиты : [б. и.], 1979.

we can state that the disturbances in the morning of Dec. 1./2. are more intensive and cover larger area than in the morning of Dec. 11./12. Magnetic disturbances are stronger and their latitudi nal distributions are wider also on Dec. 1./2. than on Dec. 11./12. hence high intensity red aurora observed and increased soft precipitation are associated with more in tense disturbances in our case. As it was mentioned above the intensity of 6300 A [Oil in the morning red aurora of Dec. 1/2 amounted to 10 kR and the intensity I 6300/1 5577 ratio mean value was equal to 3 f 5. Such spectral characteristics and intensities of the red events is quite similar to that observed in the dayside polar cusp under disturbed conditions. According to Petersen and Shepherd [ll] the ratio I 6300/1 5577 obser ved on the ground was equal to 2 r 4 and the intensity of 6300 A 01 reached 1-4 kR. Very like values were regis tered in the Heiss Island ( A = 74°) observations of Dec. 12/13 1972 [12]. Yevlash^in [ 13 ] and Sandford [14] independently pointed out for the first time the prevalence of the red A-type auroras on the high latitude stations or on so called cusp latitudes in the Arctic and the Antarctic. Later in the work [l 5 ] the latitude variations of polar auroras of 6300 A emission were given and in the work [1б] the diurnal appearance of red А-type auroras on the Heiss Island was examined with one maximum near local noon. In the auroral zone as it was shown in [ 17 ] there are three maxima of the red А-type auroras appearance probabi lity and the morning and the evening maxima were attributed to phenomenon that is connected with broadening of the cusp region to the morning and evening sides of the auroral oval. Frank [18] and Frank and Gurnett [ 19 ] assumed the possi bility of plasma flow from the day side to night along the flanks of the magnetosphere and Hultqvist [20] and McDiar- mid et al. [21] argued that characteristics of the magneto sphere plasma may reveal themselves at any local time.