Investigation of stability of long-period   
planar satellite motions in a circular orbit        

V.V.Sidorenko, A.I.Neishtadt

The aim of this paper is to investigate under the linear 
approximation the stability 
of planar motions -- one-parameter family of special solutions  of 
satellites attitude motion equations in case of  circular  orbit. 
Asymptotic  formulae  characterizing  properties  of 
planar motions with a period substantially  greater  the  orbital 
period are derived. Using these formulae it is possible to reveal the 
alternation of stability and unstability  regions  in 
the case of family parameter change.