The problem of the existence, branching and stability of the steady mo
tions of a system of two elastically coupled bodies in a central gravi
tational field is considered. Each body is simulated by a weightless r
od with point masses at opposite ends. It is assumed that the rods are
elastically attached at their mass centres, and the composite body is
moving in a plane containing the attracting centre. Both trivial and
non-trivial steady motions are studied, on the assumption that none of
the principal axes of inertia of the body coincides with the radius v
ector of the centre of mass or with a tangent to the orbit; it is also
assumed that the rods are not orthogonal to one another. The stabilit
y of all steady motions is fully investigated and an atlas of bifurcat
ion diagrams presented. (C) 1998 Elsevier Science Ltd. All rights rese
rved.