COMMISSION 27 OF THE I. A. U.
       INFORMATION BULLETIN ON VARIABLE STARS
                   NUMBER 458


                              Konkoly Observatory
                              Budapest
                              1970 August 1



               NOTE ON KM Cas



     As pointed out by L. Wackerling in Information Bulletin
No. 436, the spectral type of KM Cas is given as M6e alpha in the General
Catalogue of Variable Stars although in several other publications it is
classified as an OB star. On this account Wackerling suggested that
the star might be of the VV Cephei type.
     I have examined several infrared objective prism plates,
taken in the early 1950's, that cover the position of this star. In no
case does the star, identified from Kholopov' s identification chart
(Kholopov 1949), appear to be an M star, although its recognition as
such would be quite unambiguous if the type were as late as M2. The
small amplitude of the light variation precludes the possibility of
spectral variation from M6 to M1, and the fact of the case appears to
be that the GCVS simply erred in assigning the M6 type. This error
evidently came about through assuming the variable to be identical with
the M star Dearborn 25762 (Lee et al 1947), an identification made by
Kukarkin et al (1949). The latter reference was suggested to me by
W. P. Bidelman. The M star has also been classified and published by
Nassau and Blanco (1954). My plates show both the variable and the
M star.
     The coordinates of both stars have been measured on a Burell
Schmidt direct plate, using four nearby Smithsonian Astrophysical Observatory 
Catalogue stars as reference stars. The results are:
                          Rect. (1900)       Decl.
                KM Cas   2h21m58s7      +61  2'54"
        Dearborn M 25762 221  42.4      +60 59 01
          = Case M 140

The position for KM Cas is in excellent agreement with that given in the
GCVS; that for the M star differs by about 3' in each coordinate from
the Dearborn position (which is also different from the GCVS position),
but agrees well with the published Case position.
         
      Since KM Cas is a B star, its variable classification as SRa
is also in error. My plate material is insufficient to establish the correct 
classification.


      July 22, 1970

                          C. B. STEPHENSON
                       Warner and Swasey Observatory
                          East Cleveland, Ohio

References:
        Kholopov, P.N. 1949, Peremenn. Zvezdy, 7, 101.
        Kukarkin, B.W., Parenago, P. P., Efremov, J. I., and
Kholopov, P.N. 1949, 45th Name-List  of Variable Stars (Akademia
Nauk, Moscow).
        Lee, O.J., Gore, T., and Bartlett, T.J. 1947, Ann. Dearborn 
Obs., V. Part 1C.
        Nassau, J. J., and Blanco, V.M. 1954, Astrophys. J., 120.118.[BIBCODE 1954ApJ...120..118N ]