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.

One example of red corona recorded at Muonio is shown in Pig. 2a. For technical reason the figure is a black-and- white reproduction of colour film. Diffuse arcs sometimes with weak ray structure, appeared between the coronas. These arcs can often be seen during morning hours, though more ra rely than patches and weak diffuse airglow. Fig. 2b gives all-sky data from Loparskaya during red coronas and between them. On Dec. 11/12. the only cloudless Finnish station was Kevo. The recording started at 15*30 UT, and before 18.00 only ra ther faint westward moving bands were in the whole sky. Bet ween 18.00 and 18.30 bright active bands travelled from east and formed a loop over the station.The loop travelled to west and the activity calmed down leaving only faint bands over the whole sky. After 19.40 the active rayed bands became brighter and at 20.10 they developed a huge loop that circulated around the horizons of the all-sky picture in the north, east and south. The loop moved toward west and before reaching the zenith of Kevo it faded away while the rest of the auroral forms con tinued their westward movement. At 20.40 the northern sky and zenith were clear without aurora. Before the auroral breakup, which took place at 20.48 UT, auroral forms were weak and located close to the southern ho rizon of Kevo. The auroral arcs had multiple structures and a clear fading was seen around 20.45. After breakup the southern most arc stayed quiet even if the expanding forms had spread over the zenith of Kevo. The main activity travelled from east as in the Dec. 1./2. event. The recover phase was observed after 21.08 with diffuse and pulsating forms. This activity decreased until 23.00 when only a quiet arc remained in the south. Active rayed bands started to move in south after 00.00 UT. Between 00.20 - 00.25 an unusual event was observed. An ac tive band moved from east to west over the zenith of Kevo while in the southern sky, 30 °over horizon, a band moved from west to east. Same happened a few minutes later: between 00.29 - 00.45 wavelike bands in north moved westwards and in