COMMISSION 27 OF THE I. A. U.
      INFORMATION BULLETIN ON VARIABLE STARS
                   NUMBER 743

                               Konkoly Observatory
                               Budapest
                               1972 November 29



    IDENTIFICATION OF THE CSV 6150 WITH A GALAXY



  In 1959 Becker and Purgathofer (1959) discovered a diffuse 
object in the field of the cluster NGC 1807. The estimates 
of its brightness (11.7m-16m) on the plates and prints
obtained with different instruments permited to suspect its
variability; it was entered in the Catalogue of Suspected
Variables (CSV 5150)(Kukarkin et al., 1965; Perova, 1964).
  According to Purgathofer (1951) the star cluster NGC
1807 appears a nonphysical grouping. In this region on the
Palomar prints there are many galaxies looking like CSV
6150. CSV 6150 is probably a compact elliptical galaxy. It
is included by Zwicky in his Catalogue (Field No. 459; alpha=5h07.9m;
 =+16d25', 1950) where it is mentioned as a compact galaxy
having an integral magnitude of 15.7m (obtained with a strich-
system).
   This case reminds of other doubtful discoveries of variability 
of the galaxies (NGC 404; Geyer, 1972). Evidently, such
discoveries are connected with the observations of the extended 
diffuse  objects under very different conditions and with
different instruments (Kukarkin et al, 1972). It is clear for
galaxies, but it is not so obvious for quasars. The careful
photoelectric and photographic observations of QSS 3C 273 
reveal only small fluctuations in light in the last decade (Lyutyi
et al. 1971; Kurochkin, 1969). Probably, this object is essentially 
constant.
   The variability of the compact galaxy AP Lib (other 
unreal "variable star") is also doubtful (Kurochkin, 1972).  AP Lib
looks like CSV 6150 on Palomar Charts.
   The variations of brightness of galaxies relative to stars
probably depend on their surface brightness and concentration
of the light to the centre of the galaxy. It is found by some
observers that the nearby galaxies have amplitudes up to a few
magnitudes; more distant and compact galaxies up to 0,5m-1m;
at Last, for the majority of QSS the amplitudes are smaller
(0.2m-0.7m). Large amplitudes were detected only for a few 
objects: 3 C 345., 3 C 393, 3 C 446 etc. The variations of the
light of 3 C 446 looked as an outburst of unusual slow supernovae 
(observations in ultraviolet because of red shift; 
Kurochkin, 1972b).
   The objects of BL Lac and OJ 287 type are probably not
related to QSS; they are objects of an unusual new type with
large and continuous variability (Kurochkin, 1971b).
   It appears from this that the variability of the galactic
nuclei (also diffuse objects with large concentration) may be
fictitious (Kurochkin, 1972a).
   It is necessary to make careful analysis of data on the
variability of galaxies and quasars.




                      N.E. KUROCHKIN
                  Sternberg State Astronomical
                  Institute, Moscow, 117234.



References:

Becker W., Purgathofer A. 1959, Circ. IAU No. 1685, HAC 1444.
Geyer E.H., 1972, IBVS No. 614.
Kukarkin  et al. 1965, The Second Catalogue of Suspected
      Variable Stars, Moscow.
Kukarkin B.V., Kurochkin N.E., 1972, IBVS No. 636.
Kurochkin N.E., Perem.Zv.(USSR) 16, No. 5, 568. [BIBCODE 1969PZ.....16..568K ]
Kurochkin N.E., 1971a, Astr.Circ. (USSR) No. 602. [BIBCODE 1971ATsir.602....3K ]
Kurochkin N.E., 1971b, Astr.Circ. (USSR) No. 644. [BIBCODE 1971ATsir.644....1K ]
Kurochkin N.E., 1972a. Astr.Circ. (USSR) No. 702. [BIBCODE 1972ATsir.702....6K ]
Kurochkin N.E., 1972b, Sternberg Institute Ann., (USSR) 43,107. [BIBCODE 1972TrSht..43...89K ]
Lyutyi V.M., Cherepashchuk A.M., 1971. Astr.Circ. (USSR) No. 647. [BIBCODE 1971ATsir.647....1L ]
Perova N.B., 1964, Perem.Zv. 15, No. 2, 220.
Purgathofer A., 1961, Zf AP 52,186 [BIBCODE 1961ZA.....52..186P ]
Zwicky F., et al. 1965, Catalogue of Galaxies, V. [BIBCODE 1965cgcg.book.....Z ]