This edition was organised by Anastassios Petropoulos of the Jet Propulsion Laboratory Outer Planets Mission Analysis Group. The problem statement was released to the community on the 7th November 2006.
In a nutshell
7075 asteroids were divided into 4 groups and a low-thrust propelled spacecraft had to visit one asteroid belonging to each group for a period of at least 30 days. The objective function was the ratio between the final spacecraft mass and the total mission time.
Led by Lorenzo Casalino and Guido Colasurdo, the team from Turin Polytechnic won this edition with a trajectory designed ‘by hand’ (i.e. the asteroid sequence was not the result of an algorithm) starting from the arrival asteroid aphelium. The single legs were optimized using an indirect method.
The second and third ranked trajectories were quite far off the winning solution in terms of objective function.
The problem was inspired also by the spacecraft Dawn designed by JPL to randezvous with two asteroids, Vesta and Ceres