There’s four things that make this more useful than it might first appear. First Ion engines can pack a lot of DeltaV when you essentially have zero payload beyond an attachment device.
Next most unguided mass is still in a small number of giant objects so we don’t need to clean everything just removing the biggest objects in the most crowded orbits prevents things from getting worse.
You don’t need to get junk into a low orbit. A highly elliptical one that just touches earth’s atmosphere will deorbit things eventually. Which then sets up for the next intercept as DeltaV as perigee magnifies where your perigee ends up. Further the goal is to intercept at a reasonably low relative velocity you don’t actually need to match each of those orbits. (You can also use earth’s atmosphere to lower your perigee essentially for free so aim for the highest orbit first and work down the list.)
Finally you don’t need to handle everything with a single device. Even just having one in a polar orbit and one in an equatorial orbit greatly reduces deltaV requirements.
* DeltaV at perigee magnifies where your apogee ends up.
Historically orbital slingshots generally make use of this effect. Technically an asteroid can passively get a boost from an orbital slingshot but probes do a burn because they get more bang from the same propelent.
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There’s four things that make this more useful than it might first appear. First Ion engines can pack a lot of DeltaV when you essentially have zero payload beyond an attachment device.
Next most unguided mass is still in a small number of giant objects so we don’t need to clean everything just removing the biggest objects in the most crowded orbits prevents things from getting worse.
You don’t need to get junk into a low orbit. A highly elliptical one that just touches earth’s atmosphere will deorbit things eventually. Which then sets up for the next intercept as DeltaV as perigee magnifies where your perigee ends up. Further the goal is to intercept at a reasonably low relative velocity you don’t actually need to match each of those orbits. (You can also use earth’s atmosphere to lower your perigee essentially for free so aim for the highest orbit first and work down the list.)
Finally you don’t need to handle everything with a single device. Even just having one in a polar orbit and one in an equatorial orbit greatly reduces deltaV requirements.
* DeltaV at perigee magnifies where your apogee ends up.
Historically orbital slingshots generally make use of this effect. Technically an asteroid can passively get a boost from an orbital slingshot but probes do a burn because they get more bang from the same propelent.