We presented here a report of all our CCD observations taken in the last six years. These observations are part of a program started in 1982 to observe systematically the satellites of the planets with the 1.6 meter refractor of the Laboratório Nacional de Astrofísica in Brazil. In particular, for Nereid, 8 photographic positions were published in 1996. The large number and the good accuracy for our CCD observations confirms the adequacy of CCD observations to obtain the astrometric position of faint satellites far from its planet.
The good distribution of the positions on the elliptic orbit allows to a fit of the orbit, which is very similar to JRT orbit. It will can be used in a future determination of the parametrs in an analytical theory of Nereid's motion.
Acknowledgements
We want to thank A.H. Andrei, for their help in this work and the staff of Laboratório Nacional de Astrofísica for the assistance during our observations. We thanks J. Berthier and P. Bretagnon for their help in the calculation of the state vector for Nereid. We thanks also Ch. Veillet by the sugestions in the final version of this paper, manly for the accuracy study. C.H. Veiga and R. Vieira Martins thanks the CNPq-Brazil for partial support of this work.
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