The original KSZ plan of photography of selected sky fields
with galaxies involves 205 areas north of -25 degrees of declination.
The programme was proposed for several observatories of the former Soviet
Union, China, Rumania and Spain. There are some resulting individual
catalogues of absolute proper motions of stars compiled at five
observatories (Kiev, Pulkovo, Moscow, Tashkent and Shanghai) according to
the cooperative programme KSZ. The ultimate goal is to combine available
catalogues in General Proper Motion catalog (GPM). At present, the compilation
of the GPM catalog of stars referred to galaxies is under work at
Main Astronomical Observatory in Kiev. A preliminary compiled catalogue
of similar kind has been constructed at this observatory by Rybka (1990).
The GPM catalog will be an updated version based on more comprehensive data
from individual catalogues and will consist of two parts. At present, the
first part of the GPM catalogue (GPM1) has been completed for the brighter
stars common with the 
Input Catalogue (HIC). The second
part will
contain all remaining stars with limiting photographic magnitude 
.
Some information about the photographic observations used for deriving the
proper motions is given in Table 1 (click here). The observations have been
carried out by means of normal (Pulkovo, Tashkent) and long-focus (Kiev,
Moscow, Shanghai) astrographs.
Proper motions have been determined from plate measurements. To derive
them, 1 to 5 pairs of plates with epoch differences from 20 to 40 years
were used. As a rule, 40-90 faint anonymous stars in the magnitude range
were selected as reference stars to obtain relative proper
motions.
The relative proper motions were then transformed to an absolute reference
frame using galaxies in each field of sky. Practically, the zero-point
calibrations were simply equal and opposite to the mean relative proper
motions of several galaxies. The list of centre coordinates of 157 areas
with galaxies in the Northern hemisphere (Deutch et al.
1955) and 46 areas in the Southern one (Fatchichin
et al. 1959) was compiled at Pulkovo and Tashkent
observatories. It contains all available galaxies in KSZ fields. The
galaxies were checked to be suitable for precise measurements in terms
of 10 number scale.
Table 1: Information about observations
The proper motion data were extracted from nearly 30 publications issued since 1952. The complete list of initial catalogues, explanation of their abbreviations, bibliographic references and some statistics are being prepared by Rybka (1995) for publication. Finally, about 80000 stars from ten individual catalogues have been included in the database. It consists of 185 fields with 550 galaxies nearly uniformly distributed over the sky north of declination -25 degrees outside the Milky Way. The size of each field is nearly 1.5 square degrees. Complete verification of the data, both manually and by computer, has been performed.