New Astrometric Reduction of the Supercosmos Plate Archive: First Results

Abstract

The arrivals of the new more accuracy reference catalogs and development of new methods and approaches for reduction astrometric data give the new life for photographic plates archives. Gaia DR2 is not only a giant step in the astrometric accuracy allowing to measure new objects it also provides plates archives observed in the past with modern accuracy. In this work we present the first results of astrometric reduction in the system of Gaia DR2 for some photographic plates that were obtained by UK Schmidt telescope (UKST) and digitized by the SuperCOSMOS scanning machine. To date the UKST has taken over 17,000 plates, the plates are stored in the Plate Library at the Royal Observatory, Edinburgh. The photographic plates are digitized to 15 bits (32768 grey levels) with a resolution of 10 microns (0.67 arcsec)/pixel). Each digitized Schmidt plate has size 32256x32256 pixels and produces about 2 Gbyte pixel data. We are making new reduction of photographic plates that allowing to provide valuable data for future researches in astrometry as well as in astrophysics. The results of our research showed some problems for further successful implement of works started to process the digitized scans with such large size in the frame of the SuperCOSMOS program. However, the internal estimation of the accuracy position of objects are better the same results of the SuperCOSMOC reduction and will be improved after the solving these problems.