COMMISSION 27 OF THE I. A. U.
         INFORMATION BULLETIN ON VARIABLE STARS
                     Number 1883

                                    Konkoly Observatory
                                    Budapest
                                    1980 December 11

                                    HU ISSN 0374-0676



    PHOTOGRAPHIC OBSERVATIONS OF THE POSSIBLE COUNTERPART
           OF THE X RAY SOURCE 1E 0643.0-1648




In IAU Circ. 3529 Chlebowski et al. communicated that this X-ray
source is identified with a star 9' south of Sirius. According
to that reference the star is optically variable and shows two
states (V = 11m and 13.5m). The object could be observed on about
60 Sonneberg astrographic plates scattered over the years 1941
to 1979. A fairly close series of 1962 October to 1963 February
shows on blue sensitive plates, variations up and down between
11.7m and 14.2m, the characteristic time-scale being roughly 25
days. Difficulties arose because of the near-by image of Sirius,
especially when linking the comparison stars to the magnitudes
in NGC 2287 of Hoag et al.







                       B. FUHRMANN
                   Sternwarte Sonneberg
                 Zentralinstitut fur Astrophysik
                  Akademie der Wissenschaften
                         der DDR