COMMISSION 27 OF THE I. A. U.
          INFORMATION BULLETIN ON VARIABLE STARS
                       Number 1149

                                Konkoly Observatory
                                Budapest
                                1976 July 7



                   TY MENSAE



   The variability of TY Men (BV 457) was discovered on Bamberg
patrol plates by Strohmeier et al. (1964). Later Schoffel and
Mauder (1967), Austin et al. (1975), and more recently Naqvi and
Gronbech (1976) studied this W UMa type binary in different photometric 
systems. We also observed TY Men between 1972 and 1975 at
the Bosque Alegre Station of Cordoba Observatory with the 1.54 m
reflecting telescope. From 363 photoelectric U, B, and V observations 
we obtained 15 times of minimum; they are listed in Table I
together with three epochs of primary minima published by the 
authors quoted above. The residuals (O-C) and epochs E are from the
following improved linear ephemeris:
       JD hel.Min.I=2442054.7961d+0.46166602d E
                         +-.0008 +-.00000051
from which the phases of the observations were computed.

   The differential light curves UBV are shown in Figure 1; the
magnitude differences are in the sense variable star-minus-comparison 
star (HD 37134). The three light curves show an asymmetry at
the bottom of primary minimum and a clear difference between the
maxima; the mean values of Max II - Max I for December 1974 -
January 1975 are :

          DeltaV=0.036m     DeltaB=0.041m    DeltaU=0.028m

Naqvi and Gronbech (c/f above) observed variations in the maxima
at different epochs. The system will be observed again in the next
observing seasons in order to detect the behaviour of these 
asymmetries.




                     EMILIO LAPASSET
                  Cordoba Observatory, Argentine


                             Table I
                Times of minimum of TY Mensae

Min.  Color    JD hel.       E       (O-C)     Author

 I          2439451.459   -5639.0   -0.002    Schoffel&Mauder
 I          2441353.986   -1518.0   -0.001    Austin et al.
II      V      1587.8250  -1011.5    0.0041   Lapasset
        B      1587.8278  -1011.5    0.0069       "
        U      1587.8267  -1011.5    0.0058       "
 I      V      1589.8952  -1007.0   -0.0032       "
        B      1589.8954  -1007.0   -0.0030       "
        U      1589.8981  -1007.0   -0.0003       "
 I             2054.797       0.0    0.001    Naqvi&Gronbech
 I      V      2319.7909    574.0   -0.0015   Lapasset
        B      2319.7880    574.0   -0.0044       "
        U      2319.7903    574.0   -0.0021       "
 I      V      2403.8166    756.0    0.0010       "
        B      2403.8160    756.0    0.0004       "
        U      2403.8156    756.0    0.0000       "
 I      V      2404.7387    758.0   -0.0002       "
        B      2404.7382    758.0   -0.0007       "
        U      2404.7385    758.0   -0.0004       "



                       [FIGURE 1]


References:
Austin, R.D., De George, M., and Fleck, R. 1975 IBVS No. 1013
Naqvi, S.I.H. and Gronbech, B. 1976 Astron.and Astrophys. 47, 2 [BIBCODE 1976A&A....47..315N ]
Schoffel, E. and Mauder, H. 1967 Veroff.Remeis-Sternw.Bamberg
      VII, 60
Strohmeier, W., Knigge, R. and Ott, H. 1964 IBVS No. 66