I was really impressed with this, while it is only a test it shows you can build a tungsten penetrator type harpoon and latch a line on to space debris. Once attached adding a small delta V even with something like an ion thruster could accelerate the deorbiting of space junk.
I dont think the delta-v for deorbiting is even necessary. You just need to agglomerate all the debris into one big mass. This will make it easier to track.
In the future, when we need some in-orbit resources, etc, we can use these. (much of the debris is spent booster stages)
That's what is being assessed with this mission. If creating a few debris with he harpoon allows you to de-orbit the whole debris, which would have generated a certain amount of small debris over time, then it can be a win if the former is smaller than the potential latter.
Also, depending on the orbit considered, the debris generated by the harpoon may be less harmful: they have typically a high surface area/weight ratio so they will deorbit fast if the altitude is low enough, like for this mission.
Yes. It,s nearly impossible to avoid, really. Space debris doesn't really look like a problem that can be solved. It can only be managed.
Other than removed selected really large pieces, such as entire derelict spacecraft, in crowded orbits like GEO where the likelihood of hitting something else is high.
Depends on what you're concerned about and where it is.
Smaller things are more likely to burn up on reentry, whereas bigger things can partially survive.
Atmospheric drag can also vary based on size and density of debris. IIRC smaller things will reenter more quickly. Which is nice, except smaller debris is harder to track (imagine looking for a fleck of paint that's 500 miles away).
However things are a little different in GEO. The good news is that orbital velocities are lower, so if you hit something it'll be less catastrophic than if you hit it at the same angle in LEO. But tracking things is much harder. In LEO you can follow the wrench that some astronaut dropped 10 years ago. But in GEO there's almost no chance. And there's much less atmospheric drag, so junk can stay up there for hundreds of years.
They won't have much of an impact, as at the altitude that they operate and for various regulatory reasons, virtually every cubesat will deorbit and burn up in the atmosphere within 25 years of the launch date, with typical times being more on the order of 5-7 years. Should we reach a point where we decide there are too many cubesats and it is becoming problematic, we slow down or stop launches entirely for a few years and the problem resolves itself.
I don't think there is any one solution to "all" space debris (perhaps there is but it seems intractable with a single solution to me). However there is always benefit in removing space debris. If this technique was only successful on pieces 5" (10 cm) in size or greater it could still get a lot of stuff out of the way. Especially things that are prone to creating Kessler cascades.
