I'm no rocket scientist, but could there be a service which knocks satellites out of orbit for people? I wonder how cost effective such a service could get. Could one mission knock 10 satellites out of orbit?
Clearing out several satellites with one vehicle is not practical though, would need too much fuel. At best one might launch several such vehicles on one launch, or if orbital fuel depots really take off soon, it may be possible to have depots in convenient locations such that deorbiting vehicles can always make a relatively cheap visit to a depot to refuel and wait for another deorbiting target. In such a setup the deorbiter would just lower one end of the orbit to speed up decay rather than dragging it all the way down to Earth.
Among other things, they're promoting a standardized docking adapter (https://astroscale.com/docking-plate/) to give satellite operators a path to either life extension (refueling and/or orbit raising) or de-orbit.
But maybe there'd be some other way to do it? There have been proposals for de-orbiting little pieces of debris from the ground with lasers, and I suppose it's possible that those approaches would scale to bigger objects (or maybe you could do it with lasers from other satellites whose orbits were fixed, or something).
Avoiding splash-over or collateral damage to other sats in or near the line-of-sight would be an issue, especially if any of those other sats might have capabilities that their nation/owner might want to keep secret. Perhaps an arrangement of vetos over particular ablation shots would suffice. Countries wanting to hide their interests in some sats could veto N times as many shots as needed, making uncovering which sats are special more difficult.
In any case, laser ablation would need much less delta-V than the usual imagery of plucky space-cowboys chasing errant sats with a net, or some such. Who knew that _Planetes_ would have such a strong effect on our collective imagination.
Some companies approaching this problem are hoping to utilize refueling depots. It adds another expensive rendezvous but it does help.
https://www.cnn.com/2022/03/01/tech/space-junk-steve-wozniak...