doi:10.1007/s10569-015-9651-2engDena, Á.Abad, A.Barrio, R.Efficient computational approaches to obtain periodic orbits in Hamiltonian systems: application to the motion of a lunar orbiterART-2015-92254In this paper, we study the problem of computing periodic orbits of Hamiltonian systems providing large families of such orbits. Periodic orbits constitute one of the most important invariants of a system, and this paper provides a comprehensive analysis of two efficient computational approaches for Hamiltonian systems. First, a new version of the grid search method, applied to problems with three degrees of freedom, has been considered to find, systematically, symmetric periodic orbits. To obtain non-symmetric periodic orbits, we use a modification of an optimization method based on an evolutionary strategy. Both methods require a great computational effort to find a big number of periodic orbits, and we apply parallelization tools to reduce the CPU time. Finally, we present a strategy to provide initial conditions of the periodic orbits with arbitrary precision. We apply all these algorithms to the problem of the motion of the lunar orbiter referred to the rotating reference frame of the Moon. The periodic orbits of this problem are very useful from the space engineering point of view because they provide low-cost orbits.2015http://zaguan.unizar.es/record/14974110.1007/s10569-015-9651-2http://zaguan.unizar.es/record/149741oai:zaguan.unizar.es:149741info:eu-repo/grantAgreement/EC/FP7/ 228398/EU/Pan-European Research infrastructure on High Performance Computing for 21st century Science/HPC-EUROPA2info:eu-repo/grantAgreement/ES/MICINN/MTM2012-31883Celestial Mechanics and Dynamical Astronomy 124 (2015), 51-71All rights reservedhttp://www.europeana.eu/rights/rr-f/info:eu-repo/semantics/openAccess