COMMISSION 27 OF THE I.A.U.
                 INFORMATION BULLETIN ON VARIABLE STARS
                              Number 2933

                                                         Konkoly Observatory
                                                         Budapest
                                                         15 September 1986

                                                         HU ISSN 0374 - 0676


                      A POSSIBLE NOVA IN CYGNUS

A possible Nova was discovered by Wakuda in Cygnus on Aug. 4 on the
patrol film taken with a camera of focal length 40cm. The brightness was
then 9.1. The star was in the field of photos taken by Huruhata for CI
Cyg, and some brightnesses around the outburst were-measured. All the
photos were taken with Kodak Tri-X films with the yellow-green filter which
gives brightness very close to visual magnitude. The results are shown in
Table I and Figure 1. In the table, observer F is S. Fujino (Hamamatsu).

                            Table I.

1986(U.T.)    mv    Obs.   1986(U.T.)    mv   Obs.  1986(U.T.)     mv    Obs.

July 18.47   [13.5   H      Aug. 6.55    9.6   H     Aug. 9.71      9.0   H
     28.59    13.0:  H            .72    9.7   W         10.40     10.0   F
     29.69   [11.1   W           7.71    8.8   W           .60     10.2   W
     31.47    10.6   H           8.48    8.6   F           .70     10.7   H
       .75    11.0   W            .63    8.5   W         11.68     10.9   H
 Aug. 4.72     9.1   W            .73    9.6   H         13.64     10.5   H
      5.45     9.7   H           9.49    8.7   W           .74      9.9   W
       .47     9.7   W            .50    8.9   H
      6.48     9.4   F            .62    8.5   F

   It is noticeable that very rapid fluctuations were observed sometimes,
amounting to more than one magnitude in a few hours.
   Three spectra with objective prisms were taken by Wakuda on Aug. 5.6,
8.6, and 9.6, using the cameras of focal lengths 20 and 47.5cm. They all
showed continuous spectra without any emission lines. Approximate blue 
magnitude measured photographically by Huruhata on Aug. 8.7 was 9.5.
   The star was examined on some seven hundred photos taken by Huruhata
since July, 1979 around CI Cyg, and no image brighter than 13.0m could not be
found. This suggests that the star would not be an common UG type.
   Preliminary visual magnitudes of comparison stars determined by Huruhata
are shown in Table II.



                      [FIGURE 1]


                      [FIGURE 2]

                Fig. 2. Finding chart.



                        Table II

                    a  8.7m    g 11.1
                    b  9.4     h 11.8
                    c  9.6     k 11.8
                    d  9.7     l 12.2
                    e  9.8     m 12.3
                    f 10.8     n 13.5


              MINORU WAKUDA                MASAAKI HURUHATA

             Kawabukuro 345                  Hodozawa 88
           Ryuyo-cho, Shiuzoka               Gotenba-shi
              438-02 Japan                    412 Japan