Thoughts on the Form of Presentation of Star Catalogue Data

Abstract

The reductions of the direct measurements necessary for obtaining the published positions and proper motions of stars are rather involved. The transformation from equatorial coordinates to galactic coordinates — and proper motion components — is rather simple, and due to the exact definition of the galactic system, galactic coordinates and proper motion components can be given with the same accuracy as equatorial ones. Since it is data in the galactic system which are primarily of interest for the galactic astronomer, it is proposed that much data be henceforth published in catalogues of star positions and proper motions. One may assume that the minority of astronomers who need the data in the equatorial system will be least likely to make mistakes in transforming them back to the more direct form in which they were observed.It is further suggested that the SAOC could be used as a base for continuous improvement and updating of a comprehensive catalogue of star positions, to be updated by the incorporation of newly available material every other year or so. Procedures by which this would be accomplished are indicated.