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1 Introduction

After prior modifications the Danjon astrolabe is a reliable instrument for solar observations (Laclare 1983). A program of astrometric observations of the Sun at $30\hbox{$^\circ$}$ and $60\hbox{$^\circ$}$ zenith distances is in progress since 1990 with the astrolabe of the National Astronomical Observatory of Cerro Calán at Santiago, Chile. This program is a contribution to the research of the orbital elements of the Earth-Moon system. However, since the results of the observations are sensible to the adopted semidiameter of the Sun, eventual variations of the apparent solar radius can be also disclosed (Noël 1997). The modifications introduced in the Danjon astrolabe of Santiago, as well as the program of solar observations and the reduction method, were described by Chollet & Noël (1993). All the individual results of the observations made since the beginning of the solar program in 1990, have been published elsewhere and are available in electronic form (Noël 1993, 1994, 1995). With this paper the data set of solar observations results of Santiago is updated with the results obtained during the period 1995-1997.


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