COMMISSION 27 OF THE I. A. U.
        INFORMATION BULLETIN ON VARIABLE STARS
                     NUMBER 450

                                Konkoly Observatory
                                Budapest
                                1970 July 17

             FLARE ACTIVITY OF UV CETI

      Photoelectric monitoring of UV Ceti was carried
out at the Auckland Observatory during the International
period Oct. 3-18, 1969. The 50 cm Zeiss reflector was used
together with an E.M.I. type 9502 photomultiplier tube and
a standard B filter. Details of the eleven flares observed
are given in the table below. A further fifteen very
doubtful flares were recorded but these are not listed,
because operating equipment troubles, makes it probable
that they are spurious events.

                     [FIGURE 1] 
                     [FIGURE 2] 

 

Date    Coverage                Total  Flare  Flare max  Duration
U.T.      U.T.                  hours   No.     U.T.              delta m
                                                           mins.    B
1969
Oct.3   1338-1350;              1h20m
        1353-1410; 1419-1536;  
        1441-1454; 1456-1506;
        1508-1513; 1548-1554;
    5   1337-1350; 1353-1411;   0 52
        1414-1435.
    6   0835-0843; 0844-0854    5 59
        0856-0910; 1000-1020;           1     10h18m56s     0.93   0.35
        1023-1045; 1051-1123;           2     11 11 08      0.95   0.30
        1126-1146; 1156-1238;
        1241-1306; 1314-1411;           3     12 59 39      2.68   1.15
        1429-1458; 1505-1548;           4     13 33 31     12.65   1.85
        1554-1610; 1612-1631;
   10   0945-1001; 1004-1021;   4 39
        1031-1034; 1204-1242;
        1245-1308; 1312-1417;           5     13 16 32      3.06   0.55
                                        6     13 45 23      8.0    0.59
        1431-1526; 1532-1620            7     14 35 19      1.26   0.60
                                        8     15 13 28       ?     0.30
        1628-1635; 1638-1645;
   11   0921-0935; 0936-0940;   3 56
        0941-0942; 0957-1011;
        1012-1019; 1021-1051;
        1134-1143; 1146-1226;
        1231-1237; 1244-1321;
        1324-1329; 1337-1358;
        1500-1523; 1525-1532;
        1556-1612; 1630-1635;
   12   1033-1036; 1154-1158;   0  7
   16   0859-0917; 0920-0928;   2 18
        0933-0944; 0946-0952;           9     09 35 36     >7.5    3.80
        0953-1004; 1008-1016;
        1017-1035; 1038-1056;
        1117-1135; 1144-1156;
        1232-1242;
   18   0855-0904; 1134-1200;   1 57
        1246-1311; 1319-1328;          10     12 53 54    >13.5    3.40
        1334-1404; 1410-1414;          11     13 39 24      2.10   0.40
        1428-1442;

           Total               21h08m








                              FRANK M. BATESON
                              B.F. MARINO and
                              W. S. G. WALKER

V.S.S. RASNZ.,
18 Pooles Road
Greerton
Tauranga
New Zealand



      Visual monitoring of UV Ceti was carried out by
members of the V.S.S.,RASNZ., during the 1969 International
observing period. Times of monitoring are listed below. No
major flares were recorded. Such minor brightenings as
were observed were not beyond the inherent errors of visual
observing and do not appear to have been flares.

1969. U.T.              Monitoring times
                             U.T.

Oct.  4                 09h00m    to    09h31m
                        10 16           10 20
                        10 21.5         11 45
      6                 09 27.5         09 30
                        09 31.5         09 36.5
                        09 42           09 59.5
                        10 04           10 52.5
      8                 10 00           10 59.5
                        11 43.5         12 53
     11                 08 40           10 23
                        10 46           11 06.5
                        11 19           11 39.5
                        11 55           12 35.5
     13                 09 41.5         10 59.5
                        10 00           11 40

                        Total           11h23m


Observers: R.W. Evans; D. Cameron; C.S. Lauder;
           R. Greiner; H. Keen.


                              FRANK M. BATESON

18 Pooles Road
Greerton
Tauranga
New Zealand