AUTOMATIC GENERATION OF LISSAJOUS–TYPE LIBRATION POINT TRAJECTORIES AND ITS MANIFOLDS FOR LARGE ENERGIES Josep M. Mondelo (1) , Esther Barrab´ es (2) , Gerard G´ omez (3) , Merc` e Oll´ e (4) (1) IEEC & Departament de Matem` atiques, Universitat Aut` onoma de Barcelona 08193 Bellaterra (Cerdanyola del Vall` es) Barcelona, Spain e–mail: jmm@mat.uab.es (2) Departament d’Inform` atica i Matem` atica Aplicada, Universitat de Girona Campus Montilivi, edifici P-IV, c/Llu´ ıs Santal´ o s/n, 17071 Girona, Spain e–mail: barrabes@ima.udg.es (3) IEEC & Departament de Matem` atica Aplicada i An` alisi, Universitat de Barcelona Gran Via 585, 08007 Barcelona, Spain e–mail: gerard@maia.ub.es (4) Departament de Matem` atica Aplicada I, Universitat Universitat Polit` ecnica de Catalunya, E.T.S.E.I.B., Diagonal 647, 08028 Barcelona, Spain e–mail: merce.olle@upc.edu ABSTRACT In this paper we present a methodology for the automatic generation of trajectories within the Lis- sajous family of 2D invariant tori around L 1 of the Spatial, Circular Restricted Three–Body Problem for the Earth–Moon mass ratio. This methodology is based on the computation of a mesh of orbits which, using interpolation strategies, gives an accurate quantitative representation of the full set of li- bration point orbits. This representation, when combined with the one obtained using Poincar´ e maps, provides a useful tool for the design of missions to the libration points fulfilling specific requirements. The same methodology applies to stable and unstable manifolds as well. As an application, a repre- sentative set of the interpolated orbits is refined to a full Solar System model based on the JPL DE403 ephemeris file. 1. INTRODUCTION The last 30 years have produced an explosion in the capabilities of designing and managing libra- tion point missions [2]. The starting point was the third International Sun-Earth Explorer spacecraft (ISEE–3) which was launched in 1978, to the vicinity of the Sun–Earth L 1 Lagrange point, to pur- sue studies of the Earth-Sun interactions in a first step of what now is known as Space Weather [3]. Since 1978, interest in the scientific advantages of the Lagrange libration points for space missions has continued to increase and to inspire even more challenging objectives that are reflected, in part, in missions such as SOHO, MAP and Genesis [8]. Also, increasing understanding of the available mis- sion options has emerged due to the theoretical, analytical and numerical advances in many aspects of libration mission design. In fact, the design strategies used for some spacecraft launched in the last years have been very successful, but much more challenging trajectories goals are already being suggested for the next few decades [7]. Within the last twenty years new analytical tools have been developed that provide approximations for many different solutions around the libration points in a number of dynamical models, and that include various types of periodic and quasi-periodic motions in their vicinity. The structure of the phase space in the vicinity of the collinear points has been studied and the fundamental motions determined, including the periodic halo orbits, as well as Lissajous trajectories and quasi-halos. The 1