COMMISSION 27 OF THE I. A. U.
         INFORMATION BULLETIN ON VARIABLE STARS
                      Number 1303

                                 Konkoly Observatory
                                 Budapest
                                 1977 July 11



            ON THE PERIOD OF BS HERCULIS



    BS Her was discovered by von Reinmuth (1930) on Heidelberg
plates, its light variation ranging from 14.0m to 16.5m ph. In the
General Catalogue of Variable Stars (Kukarkin et al., 1970) this
star is classified as a possible Mira variable of M6e-type with
light variation from 13.2m to 16.5m ph.
    In the phases close to maximum (when the star is brighter
than 14m ph) the light of BS Her was estimated from 228 
photographic and 25 photovisual sky photographs of the Plate 
Depository of Odessa Astronomical Observatory. The comparison stars
used are shown in the chart of BS Her (Fig. 1). Their photographic 
magnitudes a=11.84m, b=12.27m, c=12.56m, d=12.83m, f=13.26m, k=13.50m,
l=13.84m, m=14.04m were determined with reference to the magnitudes
of stars of area III in the "Catalogue of photographic, photovisual 
and photored magnitudes of 22 000 stars" (Voroshilov et al.,
1962). Measurements were made with the MF-2 photometer. As the
variable star and the standards are considerably spaced apart,
the zero-point of magnitudes of comparison stars may be shifted.

     Observations of 12 observational seasons are shown in
Figure 2.

The moments of maxima have been observed as well:
Max J.D.       m       E    O-C
               ph
2436108      13.00    -1   +18.3
  36444      12.00     0   - 7.2
  36804      13.02    +1   - 8.6
  37168      12.92    +2   - 6.1
  37530      12.39    +3   - 5.8
  37892      12.70    +4   - 5.4
  38266      12.72    +5   + 7.2
  38628      13.05    +6   + 7.5
  38986      12.72    +7   + 4.0
  39702*       -      +9   - 3.2


Photovisual maximum is marked by an asterisk. A certain  part
of the light curve is plotted to the photovisual degree scale:
y=0.0st, z=5.9st, t=10.7st, b=17.6st, c=24.6st, f=31.6st.
The elements are found:
Max.J.D. 2436451.2 + 361.6*E.
E and O-C are calculated with respect to these elements.
                   

                 [FIGURE 1]

                 [FIGURE 2a]
                 [FIGURE 2b]


                                  E.N. MAKARENKO
                               Odessa Astronomical
                                   Observatory

References:

Kukarkin, B.V. et al., 1970, The General Catalogue of Variable
      Stars, Moscow [BIBCODE 1970gcvs.book.....K ]
Reinmuth von, 1930, AN 238, 333 [BIBCODE 1930AN....238..333R ]
Voroshilov, V.I. et al., 1962, "Catalogue of photographic, 
      photovisual and photored magnitudes of 22 000 stars"
      "Naukova dumka", Kiev