The GTOC was born in the Advanced Concepts Team of the European Space Agency from an idea of Dario Izzo (at the time a research fellow in the team) immediately welcomed by the Advanced Concepts Team ‘management’ (at that time Andres Galvez and Franco Ongaro). It is interesting to report the concluding remarks from the first edition:

“To organise the first international competition to find the global optimal of an interplanetary trajectory was a risky idea. We saw it, a bit romantically perhaps, as a sort of “sailing challenge”, with our galaxy as the racing waters and mathematical tools as the competing boats. In keeping with this idea, we hoped each successive winner would become the host (and referee) for the next event. The competition was opened to the widest international community including industry, academia and research groups. Still it was far from certain that any of these specialists and researchers would be willing to devote their (usually scarce) free time to such a contest. As it turned out, luck was indeed on the side of those who dare, and not only seventeen different groups participated to the first contest, but the winner also accepted to carry on and organise the next event, thereby fully supporting the original vision.

With hindsight, we may say that this contest indeed fills a need, which goes well beyond the sporting challenge: since there is no obvious “best trajectory” for many deep space missions, different global optimisation models and tools are used. Comparing them proves to be difficult, if not impossible, since there are many parameters to compare and different methods work better for different classes of trajectories, and they’re usually presented with such trajectories as examples. Therefore, by taking one specific problem and asking the scientific community to measure its tools on this single problem (maximum change to the semi-major axis of the asteroid 2001 TW229 through an impact) and under the same boundary conditions, the ACT Global Trajectory Optimisation Competition has for the first time allowed such a comparison. We are confident that after some rounds we will not only be able to see how different global optimisation techniques evolve over time but also have a nice database of standardised problems with many kind of solutions against which developers can measure their own new codes.

As initiators and scientific responsible of the competition, we had the chance to follow the event from the very beginning up to the presentation of its final results in February 2006 at ESTEC, the European Space Research and Technology Centre in the Netherlands. The different teams truly represented the international community from China to the United States to the European Community to Russia. Our Japanese colleagues were extremely busy with the exciting operations of the Hyabusa spacecraft and therefore could not participate even though they followed the event closely. We received all the solutions from the different teams within two days and each one of them made us really excited. We were certainly not expecting, nor we could guess, how diverse and creative all the trajectories would have been. When we came out with what would then become the competition problem, we actually were not even sure that it was possible to invert the orbital motion of the chosen spacecraft by pure thrusting as it instead resulted from some of the solutions returned. Once more, our gratitude goes to all those who participated in the event.”