COMMISSION 27 OF THE I. A. U.
	INFORMATION BULLETIN ON VARIABLE STARS
		    Number 1940

        			     Konkoly Observatory
	        		     Budapest
		        	     1981 March 23

			             HU ISSN 0374-0676	


			CD -30d5135


  Photographic UBV magnitudes have been measured for this peculiar 
emission-line F supergiant on plates taken by Mr. B. Pettersson with the
Uppsala Southern Station Schmidt telescope at Mount Stromlo Observatory,
Australia. The results are, with an estimated error of +- 0.1 mag.:

		 V        B        U
13 Oct, 1980 	9.0      9.75  	 10.4
29 Nov, 1980 	9.15    10.0   	 10.7
 9 Dec, 1980 	9.6     10.4   	 11.15

  When compared to earlier photometry (Turner 1977, Welin 1977 and 1978),
these values indicate that the conclusion drawn by me in 1978, viz. that
the star is redder when it is bright, is no longer tenable. Rather, the
colours of the star change erratically.
  In part this may be caused by rapid variations, that make at least
photographic determinations to relate to slightly different brightness
levels. Thus from 29 Nov two U plates, and from 9 Dec two B plates, are
available, showing small but possibly significant magnitude differences,
of the order of slightly more than 0.1 mag., on 9 Dec in less than ten
minutes. (The values given, above are weighted means.)


				  GUNNAR WELIN
			    Astronomical Observatory
			         Uppsala, Sweden


References:
Turner, D. G. 1977, Astron. Journ. 82, 805  [BIBCODE 1977AJ.....82..805T ]
Welin, G. 1977, Inf. Bull. Var. Stars No. 1313
Welin, G. 1978, Inf. Bull. Var. Stars No. 1469