Fundamental astrometry - Its Present State and Future Prospects

G. Teleki

The present status of the results and accuracy of fundamental astrometry is analyzed, confining ourselves, however, to the results obtained with the azimuthal, with the meridian instruments in the first place. Special attention is given to the origins of the observational errors, characteristics of the stellar catalogs of various types, astronomical constants and questions of proper motions. A survey is given of new tendencies in this field: in classical optical astrometry as well as in radio and space astrometry. Works concerning the elaboration of the new FK5 catalogue are reviewed. The conclusion is drawn that fundamental astrometry has found its way out of stagnation and conditions are created for more intensive advance. Notwithstanding the introduction of qualitatively new methods of observation, the importance and role of the classical optical, ground-based astrometry will not be diminished in the near future - provided, however, that the accuracy of its results increases considerably. It is to be hoped that two-dimensional fundamental astrometry in the sky will develop into three-dimensional astrometry in space.