COMMISSION 27 OF THE I. A. U.
         INFORMATION BULLETIN ON VARIABLE STARS
                     Number 1646

                                   Konkoly Observatory
                                   Budapest
                                   1979 July 26



    TWO VARIABLE STARS IN THE SOUTHERN COALSACK REGION




    While obtaining photographic photometry of objects showing
H-alpha emission found by Gomez and Mendoza (1976) in the Coalsack
region, we found rather large differences among the magnitudes
obtained from different plates for their star 137.
    Since the star was not listed by Kukarkin et al. (1972),
even though it lies very near to V Mus, we decided to check its
variability measuring with the iris photometer several B and V
plates obtained by J.C. Muzzio and A. Feinstein at Cerro Tololo
Inter-American Observatory (CTIO) between 1969 and 1975. On ultraviolet 
plates obtained at the same epochs the star is too faint
to be measured, and its ultraviolet magnitude was estimated as
fainter than 16.2 mag. We also used plates obtained with the
"thin" prism and the Curtis-Schmidt camera at CTIO to derive an
approximate spectral type K6-M5.
    The chart (size about 15'x 21') shows both V Mus and the
new variable together with the stars used to calibrate the photometric 
data. The western one is the new variable.
    The adopted magnitudes for the comparison stars are:
       
             Star     V     B-V
              1      16.17  1.57
              2      15.95  1.43
              3      15.59  1.08
              4      13.95  2.48
              5      15.46  1.26
              6      15.95  0.94
              7      14.60  1.65
    
    These values were derived photographically extrapolating a
photoelectric sequence which reached only V=14.50 and B=15.40.
They may thus be affected by systematic errors but, nevertheless,
they are useful to derive the light changes of the variable stars.
The observed magnitudes of the variable stars are:

             V values
Heliocentric J.D.   New Var.   V Mus

2441537.4786        14.68      17.01
2442191.6168        14.66      16.54
2442507.8232        15.05      16.10
2442509.6584        15.06      16.18
2442509.6994        15.17      16.05
               
            B values
Heliocentric J.D.   New Var.   V Mus

2440419.4155        17.30      17.23
2440694.6592        17.17      15.65
2442191.5723        16.87      18.27
2442507.8523        17.40      17.94
2442508.8076        17.23      17.92
2442509.6883        17.22      17.87


                        [FIGURE 1]


     We are grateful to Drs. J.C. Muzzio and A. Feinstein for
the use of their plates and, to the former, also for guiding this
investigation.



                  SILVIA WALDHAUSEN and RUBEN E. MARTINEZ
               Observatorio Astronomico, Universidad Nacional
                  de La Plata, 1900 La Plata, Argentina


References:
Gomez, T. and Mendoza, E.E.: 1976, Rev.Mex.Astron.Astrof., 1,
     4, 381 [BIBCODE 1976RMxAA...1..381G ]
Kukarkin, B.V. et al.,: 1972, Special Supplement to the Third
     Edition of the General Catalogue of Variable Stars,Moscow
		[BIBCODE 1972sstt.book.....K ]