Optimization of an occulter-based extrasolar-planet-imaging mission

Anovel approach to extrasolar-planet imaging uses a pair of satellites: a telescope and an occulter, where the latter is placed in the line of sight between the telescope and the star system to be imaged in order to enhance the telescope's imaging capability. The optimal configuration of this satellite formation around sun-Earth L2 halo orbits is studied. Trajectory optimization of the occulter motion between imaging sessions of different stars is performed using a range of different criteria and methods. Thus, the global optimization problem is transformed into a time-dependent traveling salesman problem. The time-dependent traveling salesman problem is augmented with various constraints that arrive from the mission, and this problem is solved by employing simulated annealing and branching algorithms. For a concrete understanding of the feasibility of the mission, the performance of an example spacecraft, the Small Missions for Advanced Research in Technology (SMART-1), is analyzed.