COMMISSIONS 27 AND 42 OF THE IAU 
              INFORMATION BULLETIN ON VARIABLE STARS 
                           Number 3788 
 
                                       Konkoly Observatory 
                                       Budapest 
                                       14 October 1992 
 
                                       HU ISSN 0374 - 0676 
 
            PHOTOELECTRIC LIGHT CURVES OF TY PUPPIS 
 
 
  The variability of TY Pup was discovered by Hertzsprung (1928). 
Campbell (1928) made the first photometric measurements, and proved that 
TY Pup is a W UMa-type eclipsing binary, with a period of about 0.58 
days. Spectrographic observations were made by Struve (1950), but only 
one component spectrum, classified as around A9n, was detected. In 
1957, Huruhata et al. carried out photoelectric observations in three 
colours. Later, Van Houten (1971) gave out a correct period of about 
0.82 days. 
 
  The present BV-band observations of TY Pup were made one nine nights 
during January to February, 1985 at Yunnan Observatory with a 35cm 
reflecting telescope and single-channel photoelectric photometer. The 
comparison and check star were BD-20d2015 and BD-21d1986, respectively. 
612 observations were obtained at each effective wavelength. 
 
  We determined three minima from the observations. They are given in 
Table 1. These three minima along with another minimum time (Van 
Houten, 1971) were introduced into a least squares solution to obtain 
the following improved ephemeris. This ephemeris was used in 
calculating the O-C values in Table 1. 
 
           JD Hel Min. I = 2446087.1142 + 0.81929882d x E 
                                  +/-10        +/-14 


                             [FIGURE 1]

                 Fig. 1  Light curves of TY Pup

 
               Table 1 
 
JD Hel          Minimum   Cycles   O-C 
2446000+ 
     86.2934      I        -1.0  -0.0015 
     87.1161      I         0.0   0.0019 
    107.1867      II       24.5  -0.0003 
 
 
 
  The B, V light curves are shown in Figure 1. The new light are 
different from Huruhata et al.'s light curves. The analysis of the 
observations will be published in a Chinese or foreign astronomy 
journal. 
 
 
                          GU SHENGHONG 
                          LIU QUINGYAO 
                          Yunnan Observatory 
                          Academia Sinica 
                          Kunming, China 
 
 
References: 
 
Campbell, L., 1928, Harvard Bull. No. 858 
Hertzsprung, E., 1928, Bull. Astron. Inst. Neth., 4, 153  [BIBCODE 1928BAN.....4..153H ]
Huruhata, M., Kitamura, M., Nakamura, T., Tanabe, H., 1957, Ann. Tokyo 
  Astron. Obs. Second Series, 5, 31 
Van Houten, C. J., 1971, Astron. Astrophys., 14, 487  [BIBCODE 1971A&A....14..487V ]