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Economics could solve it, if orbital manufacturing finds it cheaper to collect space junk for raw material than to boost it to orbit or mine it from asteroids.

Economics could solve it, if orbital manufacturing finds it cheaper to collect space junk for raw material than to boost it to orbit or mine it from asteroids. If we can defer it long enough to get to that stage an incipient orbital buzz saw may have a silver lining.

exe34 2y ago
collecting objects at orbital speed from any direction is a tricky engineering challenge.
- bell-cot 2y ago
  Understated. A Falcon 9 can put ~20,000kg into LEO for ~$40M - so $2/g. The cost of deorbiting little space junk is many orders of magnitude higher than that. And deorbiting is far cheaper than capturing and recycling.
  - sebzim4500 2y ago
    Not sure where you are getting the $40M. That's much less than the sticker price, and probably much more than the actual marginal cost of a launch.
    - bell-cot 2y ago
      You are correct (as far as I know), but: https://en.wikipedia.org/wiki/Fermi_problem https://en.wikipedia.org/wiki/Fermi_problem No point to looking up the current exact price, nor payload, when removing orbital junk is multi-million-dollar ante game, and state-of-the-art is "a few engineering prototypes exist". The bottom line (that we're many orders of magnitude away from economically recovering small space junk as raw material) would be true whether the cost of launch was $20/g or $0.20/g.
  - asadotzler 2y ago
    Falcon 9 can put 17.4 t to LEO (demonstrated with a 2023 Starlink launch) for ~$20 million (estimated SpaceX cost, not retail price) which is closer to $1.15/g. Again, that's cost not price. That's what the state of the art can do in a best case, but probably highly repeatable and reliable scenario, today.
simiones 2y ago
I'm pretty sure that collecting objects from a field of debris where every object is moving at speeds of up to 30,000 km/h relative to other objects, in random directions, is much more of a scientific challenge before even looking at economic incentives for it.
- Me1000 2y ago
  Exactly. People forget (or simply don't know) that orbital plane changes are incredibly expensive from an energy perspective. It's not like you're walking down the road picking up trash in a row, you have to adjust your orbit, canceling out movement in one direction while adding movement in another. And it takes an incredible amount of energy even for minor plane changes.
- lazide 2y ago
  Especially since most of the debris is widely spread, and often as small as a pea.
- ooterness 2y ago
  Exactly. It's like mining lead from the bullets flying through an active battlefield. There's material there, but it's moving in different directions.
- bsder 2y ago
  I thought that the only effective way to clean this is ground-based focused energy. And even that has absolutely absurd energy requirements. Everything else is in the realm of science fiction.
deleted 2y ago
[deleted]
schiffern 2y ago
People are focusing on the technical challenge, but there's a deeper issue with this idea: using mining is solving the problem "by side-effect." The way economics is supposed to solve this sort of problem is via liability (and probably insurance). This doesn't require solving the space mining problem, just an actuarial problem. But of course, the problem is that certain international actors wouldn't accept any sort of rules-based accountability for damage when it's caused by their space junk.
- adolph 2y ago
  > The way economics is supposed to solve this sort of problem “The curious task of economics is to demonstrate to men how little they really know about what they imagine they can design.” ― Hayek
- KennyBlanken 2y ago
  Yup, just like the problem with plastics is "solved" by recycling, which only manages to handle a fraction of the plastic generated, doesn't address microplastic pollution, and the economic viability of recycling is incredibly poor, in part because the polymers break down quite a bit with use/age/reprocessing.
  - trashtensor 2y ago
    Plastics, climate change, we have a number of these problems that get worse over a long enough time scales that there is no incentive for the people in charge of our economy to fundamentally change their behavior. I find "economics will solve this" arguments really dubious.
    - exe34 2y ago
      the market only really works when the perpetrators pay the cost.
  - bryanlarsen 2y ago
    Recycling works great for lots of resources: lead-acid batteries, steel, aluminum, etc. Just because it doesn't work well for one resource doesn't make it non-viable.
raincole 2y ago
> if orbital manufacturing finds it cheaper to collect space junk This is a giant "if" that generates enough gravity to pull all the space junk into a ball.
- deleted 2y ago
  [deleted]
PaulHoule 2y ago
It is not always cheap to change orbit around Earth, the old Heinlein quote: "If you can get your ship into orbit, you're halfway to anywhere." is mostly wrong. If you wanted to send up a satellite to pick up little bits of trash and bring them to one place for processing you would have to use fuel to maneuver from one to another: it is cheap to change the https://en.wikipedia.org/wiki/True_anomaly https://en.wikipedia.org/wiki/True_anomaly but other orbit changes in LEO can be about as expensive as launching a rocket up from Earth. There is no point, for instance, in sending a cargo to the space station and then launching it in a polar orbit. The space station we have has no potential as a staging area to go to the Moon or Mars because it is in the wrong orbit. The cost of moving things around is one reason why Terra is the low-cost source of resources throughout the solar system still. Now you can move space junk around without using fuel, instead you can hit the space junk with a laser which will evaporate off a bit of the surface and push it: https://arxiv.org/abs/1110.3835 https://arxiv.org/abs/1110.3835 the usual idea is that you use this to deorbit space junk but you could also use this to change the orbit of a piece so maybe you could gather a bunch of them in one place or maybe somebody could use such a laser to engineer collisions. The laser they describe in that paper is almost like a tractor or pressor beam from science fiction.
- aftbit 2y ago
  I would like to see a website/app/program that can generate Delta-V charts like this one, but with different bodies and transfer orbits for scale. https://space.stackexchange.com/questions/2046/delta-v-chart-mathematics https://space.stackexchange.com/questions/2046/delta-v-chart... IMO Orbital mechanics is very unintuitive, and one of the results in people asking things like "why not shoot all of our trash into the Sun?"

exe34 2y ago

collecting objects at orbital speed from any direction is a tricky engineering challenge.

bell-cot 2y ago
Understated. A Falcon 9 can put ~20,000kg into LEO for ~$40M - so $2/g. The cost of deorbiting little space junk is many orders of magnitude higher than that. And deorbiting is far cheaper than capturing and recycling.
- sebzim4500 2y ago
  Not sure where you are getting the $40M. That's much less than the sticker price, and probably much more than the actual marginal cost of a launch.
  - bell-cot 2y ago
    You are correct (as far as I know), but: https://en.wikipedia.org/wiki/Fermi_problem https://en.wikipedia.org/wiki/Fermi_problem No point to looking up the current exact price, nor payload, when removing orbital junk is multi-million-dollar ante game, and state-of-the-art is "a few engineering prototypes exist". The bottom line (that we're many orders of magnitude away from economically recovering small space junk as raw material) would be true whether the cost of launch was $20/g or $0.20/g.
- asadotzler 2y ago
  Falcon 9 can put 17.4 t to LEO (demonstrated with a 2023 Starlink launch) for ~$20 million (estimated SpaceX cost, not retail price) which is closer to $1.15/g. Again, that's cost not price. That's what the state of the art can do in a best case, but probably highly repeatable and reliable scenario, today.

simiones 2y ago

I'm pretty sure that collecting objects from a field of debris where every object is moving at speeds of up to 30,000 km/h relative to other objects, in random directions, is much more of a scientific challenge before even looking at economic incentives for it.

Me1000 2y ago
Exactly. People forget (or simply don't know) that orbital plane changes are incredibly expensive from an energy perspective. It's not like you're walking down the road picking up trash in a row, you have to adjust your orbit, canceling out movement in one direction while adding movement in another. And it takes an incredible amount of energy even for minor plane changes.
lazide 2y ago
Especially since most of the debris is widely spread, and often as small as a pea.
ooterness 2y ago
Exactly. It's like mining lead from the bullets flying through an active battlefield. There's material there, but it's moving in different directions.
bsder 2y ago
I thought that the only effective way to clean this is ground-based focused energy. And even that has absolutely absurd energy requirements. Everything else is in the realm of science fiction.

deleted 2y ago

[deleted]

schiffern 2y ago

People are focusing on the technical challenge, but there's a deeper issue with this idea: using mining is solving the problem "by side-effect." The way economics is supposed to solve this sort of problem is via liability (and probably insurance). This doesn't require solving the space mining problem, just an actuarial problem. But of course, the problem is that certain international actors wouldn't accept any sort of rules-based accountability for damage when it's caused by their space junk.

adolph 2y ago
> The way economics is supposed to solve this sort of problem “The curious task of economics is to demonstrate to men how little they really know about what they imagine they can design.” ― Hayek
KennyBlanken 2y ago
Yup, just like the problem with plastics is "solved" by recycling, which only manages to handle a fraction of the plastic generated, doesn't address microplastic pollution, and the economic viability of recycling is incredibly poor, in part because the polymers break down quite a bit with use/age/reprocessing.
- trashtensor 2y ago
  Plastics, climate change, we have a number of these problems that get worse over a long enough time scales that there is no incentive for the people in charge of our economy to fundamentally change their behavior. I find "economics will solve this" arguments really dubious.
  - exe34 2y ago
    the market only really works when the perpetrators pay the cost.
- bryanlarsen 2y ago
  Recycling works great for lots of resources: lead-acid batteries, steel, aluminum, etc. Just because it doesn't work well for one resource doesn't make it non-viable.

raincole 2y ago

> if orbital manufacturing finds it cheaper to collect space junk This is a giant "if" that generates enough gravity to pull all the space junk into a ball.

deleted 2y ago
[deleted]

PaulHoule 2y ago

It is not always cheap to change orbit around Earth, the old Heinlein quote: "If you can get your ship into orbit, you're halfway to anywhere." is mostly wrong. If you wanted to send up a satellite to pick up little bits of trash and bring them to one place for processing you would have to use fuel to maneuver from one to another: it is cheap to change the https://en.wikipedia.org/wiki/True_anomaly https://en.wikipedia.org/wiki/True_anomaly but other orbit changes in LEO can be about as expensive as launching a rocket up from Earth. There is no point, for instance, in sending a cargo to the space station and then launching it in a polar orbit. The space station we have has no potential as a staging area to go to the Moon or Mars because it is in the wrong orbit. The cost of moving things around is one reason why Terra is the low-cost source of resources throughout the solar system still. Now you can move space junk around without using fuel, instead you can hit the space junk with a laser which will evaporate off a bit of the surface and push it: https://arxiv.org/abs/1110.3835 https://arxiv.org/abs/1110.3835 the usual idea is that you use this to deorbit space junk but you could also use this to change the orbit of a piece so maybe you could gather a bunch of them in one place or maybe somebody could use such a laser to engineer collisions. The laser they describe in that paper is almost like a tractor or pressor beam from science fiction.

aftbit 2y ago
I would like to see a website/app/program that can generate Delta-V charts like this one, but with different bodies and transfer orbits for scale. https://space.stackexchange.com/questions/2046/delta-v-chart-mathematics https://space.stackexchange.com/questions/2046/delta-v-chart... IMO Orbital mechanics is very unintuitive, and one of the results in people asking things like "why not shoot all of our trash into the Sun?"