Improvement of the Optical Reference System by Photographic Astrometry: First Results of Simulations with Global Block Adjustment Methods

Abstract

AbstractBlock adjustment (BA) simulations of an entire hemisphere show major improvements in individual as well as systematic accuracy of star positions obtained by photographic astrometry, independent of systematic errors of the reference star catalog used. Results for the accuracy estimates obtained from a patch-like plate pattern in the sky are not valid for closed plate pattern. The importance of BA methods for the realisation of a reference system is stressed.