COMMISSION 27 OF THE I. A. U.
          INFORMATION BULLETIN ON VARIABLE STARS
                     Number 3148



                                     Konkoly Observatory
                                     Budapest
                                     19 February 1988

                                     HU ISSN 0374-0676


        LIGHT CURVE OF V482 CYGNI, AN R CrB STAR

    There are some 700 plates at the Maria Mitchell Observatory
with useful images of V482 Cyg. This R Coronae Borealis variable
has recently been studied in the infrared by Gaustad et al.
(1988), who discuss its association with three close companions
and determine its absolute magnitude on the reasonable assumption
that the association is a physical one. The Maria Mitchell data
through 1970 had been reported by Esther Hu (1971). At the
suggestion of John Gaustad, we have extended her work.

    Figure 1 is the photographic light curve through January
1988. The magnitudes are estimates relative to B. S. Whitney's
(1949) photographic sequence augmented by a star of magnitude
15.4 pg, from Wachmann (1966). We made one other change in
Whitney's sequence. On our plates the star marked b on his chart
looks about 0.6 mag too faint, relative to its neighbors, for its
published magnitude, 12.05 pg. A reasonable although not a unique
explanation for the discrepancy is that the wrong star is marked
on Whitney's chart. There is a somewhat brighter star 11 arcmin
north preceding and we have calibrated our magnitude estimates on
the assumption that Whitney's magnitude 12.05 refers to this star.
A curve through his photographic mean points is superimposed on
the Maria Mitchell data in Fig. 1. The agreement is entirely
satisfactory.

    V482 Cyg is typically 12.2 in maximum and can drop below
15.4. The start of the current minimum was suspected by JD
2447030 (August 1987). The magnitude reached 13.0 by 2447115
(November), and thereafter the drop has been rapid, as reported
in IAU Circulars 4511 and 4515. The current faintness of the
variable provides a good opportunity for observers with


                        [FIGURE 1]

 Figure 1. Photographic light curve of V482 Cygni. The circles
 indicate low weight. The symbol V means that the variable was
 fainter than the indicated magnitude.


appropriate equipment not only to study conditions in minimum
but also to get data about the fainter companions. Gaustad et
al. estimate that their V magnitudes are in the range 13.6-16.8.
They are all within 7 arcsec of the variable.

  We gratefully acknowledge grants AST-8320491 and AST-8619885
from the National Science Foundation in support of variable star
research at the Maria Mitchell Observatory.


EMILIA P. BELSERENE, DAVID L. SUMMERS, ELLEN A. SCHEER
  Maria Mitchell Observatory
  Nantucket MA 02554 USA



References:

Gaustad, J.E., Stein, W.A., Forrest, W.J., and Piper, J.L.
  1988. Pub. Astr. Soc. Pacific, March 1988, in press. [BIBCODE 1988PASP..100..388G ]
Hu, E. 1971. AAVSO Abstracts, Oct. 1971, p. 16. [BIBCODE 1971aavs.book...16H ]
Wachmann, A.R. 1966. Astr. Abh. Hamburg. Stw. Vol. VI, 379.
Whitney, B.S. 1949, Astrophys. J., 109, 538. [BIBCODE 1949ApJ...109..538W ]