COMMISSION 27 OF THE I. A. U.
            INFORMATION BULLETIN ON VARIABLE STARS
                          Number 966

                                     Konkoly Observatory
                                     Budapest
                                     1975 February 25


                           CSV 7917

    A possible Nova Scuti 1958 was reported by the late S. 
Apriamishvili (1962) (the coordinates in that report are for 1950, not
1900), and on this account it is No. 7917 in the Catalogue of Stars
Suspected of Variability. I shall refer to this catalogue as the
CSV.
    I have noted that an S star found here some years ago, No. 12
in Table 2 of the paper by Nassau, Blanco, and Morgan (1954), is
variable and quite close to the position of CSV 7917. Kharadze and
Dolidze of Abastumani Observatory have very kindly made available
to me photographic prints from Apriamishvili's discovery plate, and
comparison of these with the Case material leaves no doubt that
S-WS 12 and CSV 7917 are the same star. It is missing from the blue
Palomar Sky Survey print, as Apriamishvili had noted, and which 
supported his suspicion that the star was a nova. However, it appears
to be present on the red print; I was assisted in reaching this 
conclusion by our fortunate possession of a transparency of the red
Palomar print, made to the scale of our Burrell Schmidt plates.
    The accompanying chart, from the red Palomar print, shows the
star in a field approximately 6' in radius.
    Apriamishvili discovered the star from its H-alpha emission, and
this plus my previous remarks suggest that it is a long-period 
variable. However, the situation may not be that simple; the Abastumani
people do not think their spectrum is type S, and mv plates (chiefly
infrared) do not establish the form of the light curve. I can only
say the following: The star was bright on May 27 and June 19, 1947;
July 20, 1952; July 12, Aug. 12, and Sept. 8, 1955. It was faint (at
least two mags. fainter, and usually invisible) Aug. 2, 1951; July 4,
1959; and July 30, 1962. As this summary suggests, my material is 
inadequate for meaningful determinations of magnitude values.
    Kharadze feels that the Abastumani discovery spectrogram is
like a Wolf-Rayet star. This circumstance, and Apriamishvili's failure 
to find the star on a number of other plates, suggests possible
membership in, or relationship to, the Z Andromedae group; if this
is the case, it is the first one in which the cool component is S-
type. Somewhat against this, and perhaps favoring the long-period
variable status, is the fact that my material shows the S-type 
spectrum to be distinctly variable in flux in the photographic infrared.
    My only spectral plates that give useful information about the
spectrum are infrared (there is one unwidened red-region spectrum,
of uncertain character), and appear mostly to show a red continuum
with the {lambda} 7909 La0 band characteristic of S-type stars.


                            [FIGURE 1]



                                    C. B. STEPHENSON
                               Warner and Swasey Observatory


References:

Apriamishvili, S. 1962, Astron.Circ. No. 229, 1 [BIBCODE 1962ATsir.229....1A ]
Nassau, J.J., Blanco, V.M., and Morgan, W.W. 1954, Astrophys.J.,
              120, 478 [BIBCODE 1954ApJ...120..478N ]