We are able to track the trajectories of space junk right?
If we could have a small robotic satellite that would somehow stop the orbiting mass (I'm thinking something like a "harpoon" like device that can attach and then reel in). Load it into a capsule that can then be jettisoned to land on earth.
Obviously some analysis has to be done, including what sort of numbers we're looking at (I don't know what the velocity or how much mass these defunct satellites are, nor how dense they are in space and how often they might come past a single point).
Is there any prior work / thoughts about space junk in a "recycling" sense?