Effect of weak perturbations on the relative motion of two satellites

The preprint studies the influence of the weak perturbations on the relative motion of two small satellites. We consider weak eccentricity of the orbit of main satellite, sun pressure that affects a daughter satellite, and aerodynamic resistance. In order to illustrate the latter a motion of the technology nanosatellite TNS-0 with respect to the International Space Station is considered and, also, a comparison of the motion calculated using the approximate formulas and by processing the NORAD two-line element sets, respectively, is carried out.