Petites planetes Hipparcos:
Conditions de determination des masses. 

J-F. Bange, A. Bec-Borsenberger

Service de Mecanique Celeste du Bureau des Longitudes, URA CNRS
707, 77 avenue Denfert-Rochereau 75014 Paris, France.

ABSTRACT

The observations of minor planets are of particular interest for determining the
equinox and a possible rotation between the Hipparcos and the dynamical
reference frames. In order to evaluate these unknowns, Hipparcos data are
compared to the values calculated from the equations of motion. The associated 
equations of condition involve in addition orbital elements and masses of 
minor planets. 
In this paper, we present the favourable conditions of the masses determinations(close approaches) and the selection of particular cases that is being done. 
We show with examples which precision it is possible to expect from these data.