Space Junk Has Already Hit the Tipping Point
…long-term models tell us there are really only two ways to reduce the threat of collisions in orbit. One is to actively remove debris from densely populated regions of space, drawing the large object population back down below the tipping point.
The other is to perfect just-in-time collision avoidance for objects that can’t change direction under their own power, executing maneuvers (for example, by puffing gas into the path of a piece of debris) that could prevent collisions between two derelict objects.
At the moment, we don’t have the technology needed to pursue either of these options, and it’s still unclear what national or international agencies should be responsible for pursuing them.
Alarmingly, it may take hundreds of billions of dollars or more to clean up the debris environment over the next century in order to ensure reliable space operations. There isn’t even a clear legal statute that precisely defines ownership and liability issues for derelict object removal operations, and any international effort will likely struggle against trade and export restrictions that can limit technology development and sharing.
(via We’ve Already Passed the Tipping Point for Orbital Debris - IEEE Spectrum)