Kinematic constraints between stellar systems in superposition

Some kinematic consequences of a superposition of two stellar systems are studied. Chandrasekhar's axially-symmetric model has been adopted for each one of the subsystems. The solution of Chandrasekhar's equations provides us with a potential function, which must be shared by both stellar subsystems and, thus, some relationships between the kinematic parameters of both, subsystems are obtained. In the case of a stationary potential function the whole set of second-order centred moments may be explained.Gotta serve somebody... (Bob Dylan) may be U may be₂.Paper presented at the 11th European Regional Astronomical Meetings of the IAU on New Windows to the Universe, held 3–8 July, 1989, Tenerife, Canary Islands, Spain.