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.