Active debris removal

Active debris removal sends a spacecraft to capture an inert object already in orbit, an abandoned launcher stage or a dead satellite, and deorbit it or move it aside. End-of-life disposal, by contrast, is an obligation on the operator of a satellite still under control. Active removal goes after objects nobody commands any more, many of them predating any disposal rule at all. Since the 2000s, orbital environment models have concluded that full compliance with disposal rules no longer stabilizes the low-Earth-orbit debris population. A few large objects would have to come down every year. That makes the technique a condition of future insurability rather than a technical curiosity. The difficulties are as legal as they are technical. The 1967 Outer Space Treaty keeps jurisdiction with the state of registry: a piece of debris cannot be captured without the consent of the state that launched it, even after thirty years of abandonment. For insurance, a removal mission combines the two profiles hardest to price, a demonstration flight and a rendezvous with an uncooperative target.