SECONDARY POLAR ZONE OF PROMINENCE ACTIVITY REVEALED FROM LOMNICKY STIT OBSERVATIONS

The time-latitude distribution of the number and area of prominences o bserved at Lomnicky Stit Coronal Station during the period 1967-1991 h as been studied in order to check if multiple structure of the promine nce polar zones can be traced. The results obtained show that a second ary polar zone appears in the northern hemisphere during the maximum p hase of solar cycle 20, which confirms the result obtained by Waldmeie r (1973). During the ascending phase of solar cycle 22 a triple struct ure developed in the southern hemisphere. No multiple structure is obs erved during solar cycle 21.