An analytical method for calculating the passive motion of a spacecraft in the vicinity of the collinear libration point of the Earth-Moon system has been developed. A general statement of the problem is given, taking into account various potential perturbations. Estimates of "disturbing accelerations". In the case of the elliptic problem of three bodies (Earth-Moon - KA), all the necessary formulas were obtained for the analytical method for calculating the kinematic parameters of the spacecraft motion according to their initial values. The method is based on Birkhoff's normalizing transformations. Keywords: limited task of three bodies, libration point normal form conditional periodic motion.