New Periodic Orbits for the n-Body Problem
  Since the discovery of the figure-8 orbit for the three-body problem [Moore 1993] a large number of periodic orbits of the n-body problem with equal masses and beautiful symmetries have been discovered. However, most of those that have appeared in the literature are either planar or are obtained from perturbations of planar orbits. Here we exhibit a number of new three-dimensional periodic n-body orbits with equal masses and cubic symmetry. We found these orbits numerically by minimizing the action as a function of the trajectories' Fourier coefficients. We also give numerical evidence that a planar 3-body orbit first found in [H\'enon, 1976], rediscovered by [Moore 1993], and found to exist for different masses by [Nauenberg 2001], is dynamically stable.   It is a pleasure to dedicate this paper to Philip Holmes. 
Cristopher Moore and Michael Nauenberg