THE BORDEAUX MERIDIAN OBSERVATIONS OF ASTEROIDS - FIRST DETERMINATIONOF THE MASS OF (11)-PARTHENOPE

The asteroid observations made with the automatic meridian circle at B ordeaux observatory from 1985 to 1994, and which have recently become available, are presented. The residuals of these observations obtained using the orbital elements published in the ''Ephemerides of Minor Pl anets for 1996'' are analysed. An anomaly for the asteroid (17) Thetis was found, indicating a current close encounter between this asteroid and (4) Vesta. Such an encounter will allow very interesting determin ations of the mass of Vesta to be made in the future. Lastly our deter mination of the mass of(11) Parthenope is discussed, which was based o n its perturbations on the orbit of Thetis. The result obtained, (2.58 +/- 0.10) 10(-12) M., appears significant.