“…As one can easily imagine, a large literature in engineering, optimization, and control, covers each of these streams, and all will eventually contribute to the above outlined directions for reducing space congestion with debris. Reviewing the literature, even only after Fliege et al (2012), is well beyond the objective of this paper and would take the readers along paths very remote from our paper's focus. To give a hint about some of the optimization techniques used in the literature, we give few examples mainly in system design and system management, one of the favorite topics in OR.…”