COMMISSION 27 OF THE I. A. U.
        INFORMATION BULLETIN ON VARIABLE STARS
                     Number 1127

                               Konkoly Observatory
                               Budapest
                               1976 April 20


          TIMES OF MINIMA OF RZ OPHIUCHI





      The eclipsing binary RZ Oph shows spectroscopic
evidence of mass transfer, and yet it is unlikely that either
star in the system fills its Roche lobe (Baldwin, unpublished).
Two recent primary eclipses were observed photoelectrically
(with B and V filters) with the 12-inch telescope of the
University of Victoria, Victoria, British Columbia. Although
not enough observations were obtained to warrant an orbital
solution, times of minima and times between contact points
were determined.


        T_min (JD) = 2,441,942.3 +- 0.2d
                     2,442,204.1 +- 0.2d

     Duration of totality           = 9.3d +- 0.2d
     Duration of each partial phase = 1.5d +- 0.2d



The uncertainties were estimated visually from the light curve.
The values for the duration of totality and the duration of
each partial phase are significantly different from those
listed in the current literature (e.g., Rocznik Astronomiczny
Observatorium Krakowskiego, 1975).

      A linear ephemeris was derived from these and an
additional 32 times of minima uncovered during a literature
search:


        T_min (JD) = (2,442,204.4 +- 0.2d) + (261.928d +- 0.003d)E,
         


where E is the cycle number. There is no evidence for a period
variation within the uncertainties of the observations.

      The next primary eclipse occurs in late July 1976, and
additional photometric observations at that time are desirable.





                           B.W. BALDWIN
                      University of Toronto
                      David Dunlap Observatory
                      Richmond Hill, Ont.
                          Canada