A&A Supplement Ser., Vol. 124, July 1997, 153-155

Received October 23; accepted November 18, 1996

Systematic differences Astrolabe-FK5 derived from observations at zenith distance

F. Noël

  Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago, Chile
  European Southern Observatory, Alonso de Córdoba 3107, Santiago, Chile

Abstract:

After instrumental modifications, series of FK5 stars were observed at zenith distance with the astrolabe of Santiago, Chile, during the period 1990-1994. The mean residuals in zenith distance for each star were obtained with an average mean error of . Analyzing the zenith distance residuals according to the star azimuths, systematic differences Astrolabe-FK5 (J1991.9) in alpha and delta as a function of delta are derived for the zone between and in declination. The average mean errors are  s and for the systematic differences in right ascension and in declination respectively. A comparison of the astrolabe results with similar ones obtained with an automatic meridian circle, is discussed.

keywords: astrometry -- reference systems

 
• 1. Introduction
• 2. Observations and reductions
• 3. Systematic differences astrolabe-FK5
• 4. Conclusions
• References