COMMISSION 27 OF THE I. A. U.
         INFORMATION BULLETIN ON VARIABLE STARS
                      NUMBER 112

                                   Konkoly Observatory
                                   Budapest
                                   1 November 1965

        CURRENT ELEMENTS FOR RZ CASSIOPEIAE


     Approximately 500 visual and 35 photoelectric timings of
minima were used by the writer to examine the period of RZ
Cassiopeiae between 1950 and 1965 /1/. Residuals indicated that
the star's period over this interval averaged about  88 x 10^-7
day less than that given by Parenago /2/, 1.1952519day.

The residuals defined four distinct slopes to the O - C
curve. The most recent change began in 1960, after which the
period of RZ Cassiopeiae was 1.1952472day. To represent recent
minima, these elements have been adopted,

             Min = JD 2437143.9886 + 1,1952472day E.
Residuals of recent visual normals /1/ to Parenago's elements /2/
and to the above elements follow.

JD nor. min.    Ep        O - Cp     Er      O - Cr  
+ 2400000

37171.4786    +16579     -0.0260     +23    -0.0007
37316.1062     16700     -0.0238     144    +0.0020
37540.8117     16888     -0.0257     332    +0.0010
37618.5045     16953     -0.0243     397    +0.0028
37893.4099     17183     -0.0268     627    +0.0013
38008.1540     17279     -0.0269     723    +0.0017
38285.4454     17511     -0.0339     955    -0.0043
38360.7505     17574     -0.0297    1018    +0.0003
38629.6798     17799     -0.0321    1243    -0.0011
38732.4696     17885     -0.0339    1329    -0.0025

1. L. J. Robinson, submitted for publication in Variable Stars.

2. P. P. Parenago, Variable Stars, 9, 2, 125, 1952.


     L. J. Robinson
   "Sky and telescope"
     49 Bay State Rd.
  Cambridge, Mass. USA.