We consider a (1+N)\documentclass[12pt]{minimal}
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\begin{document}$$(1+N)$$\end{document}-body problem in which one particle has mass m0≫1\documentclass[12pt]{minimal}
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\begin{document}$$m_0 \gg 1$$\end{document} and the remaining N have unitary mass. We can assume that the body with larger mass (central body) is at rest at the origin, coinciding with the center of mass of the N bodies with smaller masses (satellites). The interaction force between two particles is defined through a potential of the form U∼1rα,\documentclass[12pt]{minimal}
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\begin{document}$$\begin{aligned} U \sim \frac{1}{r^\alpha }, \end{aligned}$$\end{document}where α∈[1,2)\documentclass[12pt]{minimal}
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\begin{document}$$\alpha \in [1,2)$$\end{document} and r is the distance between the particles. Imposing symmetry and topological constraints, we search for periodic orbits of this system by variational methods. Moreover, we use Γ\documentclass[12pt]{minimal}
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\begin{document}$$\Gamma $$\end{document}-convergence theory to study the asymptotic behaviour of these orbits, as the mass of the central body increases. It turns out that the Lagrangian action functional Γ\documentclass[12pt]{minimal}
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\begin{document}$$\Gamma $$\end{document}-converges to the action functional of a Kepler problem, defined on a suitable set of loops. In some cases, minimizers of the Γ\documentclass[12pt]{minimal}
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\begin{document}$$\Gamma $$\end{document}-limit problem can be easily found, and they are useful to understand the motion of the satellites for large values of m0\documentclass[12pt]{minimal}
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\begin{document}$$m_0$$\end{document}. We discuss some examples, where the symmetry is defined by an action of the groups Z4\documentclass[12pt]{minimal}
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\begin{document}$${\mathbb {Z}}_4$$\end{document} , Z2×Z2\documentclass[12pt]{minimal}
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\begin{document}$${\mathbb {Z}}_2 \times {\mathbb {Z}}_2$$\end{document} and the rotation groups of Platonic polyhedra on the set of loops.
