HIPPARCOS DATA REDUCTION - CONSTRUCTION OF THE HIPPARCOS STAR CATALOG

The on-ground treatment of the Hipparcos satellite data is the largest and most complex data-analysis problem ever undertaken in the history of astrometry. Assembling a final and highly accurate catalogue of st ar positions, distances and motions presents a unique problem, both sc ientifically and from the data-management viewpoint, for the Consortiu m of European scientific institutes involved in the tasks. The develop ment of the data-analysis techniques guided the development of the sat ellite design itself. Self-checking procedures, implicit in the satell ite measurement and data-analysis techniques, demonstrate that the ult imate astrometric catalogue promised by the Hipparcos mission will sho rtly become a reality.