Astrometry of five major Uranian satellites in 1995–1997

At the oppositions of 1995–1997, a total of 122 CCD frames were taken on the 1.56 m astrometric telescope at the Sheshan station, yielding 864 positions of the major Uranian satellites. The calibration of the images was carried out using a least-squares iterative program by fitting to the well-known orbits of the brighter moons of Uranus, based on the modern theory GUST86 and an ephemeris produced by numerical integration. The residuals lay between 0\farcs03 and 0\farcs05 for each of the inter-satellite positions, except for the innermost and faintest satellite Miranda, whose residuals exceeded 0\farcs08 due to the proximity of Uranus. No significant systematic errors were found when using satellites themselves for determining calibration parameters. The largest residual in the comparison between GUST86 and the numerical integration was about 0\farcs01