Just in time collision avoidance - A review

The ever increasing number of orbital objects since 1957 raises numerous questions concerning future sustainability of space. Among the 34,000 objects larger than 10 cm in orbit, 20,000 only are cataloged. These cataloged objects include roughly 2000 active satellite, among which less than 1500 are maneuverable. All the rest are orbital debris, large satellites of launcher upper stages, mission related objects, inert pieces from fragmentations or collisions, with no maneuvering capabilities.