NEW REDUCTIONS OF THE ASTROGRAPHIC-CATALOG - PLATE ADJUSTMENTS OF THEALGIERS, OXFORD-I AND OXFORD-II, AND VATICAN ZONES

The U. S. Naval Observatory is in the process of making new reductions of the Astrographic Catalogue using a modern reference catalog, the A CRS, and new data analysis and reduction software. Currently ten AC: z ones have been reduced. This papers discusses the reduction models and results from the Algiers, Oxford I and II, and Vatican zones (those o f the Cape zone are discussed elsewhere). The resulting star positions will be combined with those of the U.S. Naval Observatory's Twin Astr ograph Catalog to produce a catalog of positions and proper motions in support of the Sloan Digital Sky Survey.