One solution that I’ve seen mentioned for helping combat climate change is offloading most of our industry to orbitals. Indeed, I have considered this concept myself.
The benefits of this idea would be that it would allow us to continue producing while harming the planet less as we’d be in a fully enclosed environment. Emissions wouldn’t go into the atmosphere and chemical waste wouldn’t pollute the waters. There is the issue of raw materials but minerals could be acquired from asteroids and meteors, for example, while organics (such as food) could be grown on the orbitals themselves.
The orbitals could be geostationary or even an orbital ring that a space elevator services. To help lessen the human impact at the loading bay, we could potentially use robotic swarms to handle the gathering and things. We could combine it with a system of tubes (such as pneumatic tubes or even maglev) to move stuff to the loading bay in a less destructive manner. We could also go another route: low tech and use draft animals to pull stuff around. That would lessen the impact even more but comes with its own set of challenges. For instance, the donkey could decide not to show up for work one day and the zebra may become lion food.
There is the issue of what to do with the waste, however. For carbon-based emissions, not replenishing the carbon we used from Earth would greatly disrupt the carbon cycle and could lead to a “carbon death” of the ecosystem if we need to keep importing carbon for food without replenishing it. Another option would be to import the carbon across multiple astronomical bodies, lessening our impact on any single unit.
As for waste, we could export the carbon to other bodies as well. This would provide a surprising benefit: it would allow us to start getting the body ready for colonization. This does contain ethical concerns such as in the case if the body already has life and doing so could disrupt its environment, however. In such a case, it would be best to probably keep it to bodies that would only be “improved”, such as large asteroids without any life. The gasses could also be exported once a magnetic field is generated to keep them from being expelled to the vast reaches of space.
Another option would be to construct bodies akin to artificial planets. These could be constructed of rock, metal, or some other very durable substance. These could be handled similar to the orbitals but, due to their size, they give us the option of potentially setting up the ecological systems to be naturally occurring. Constructing such a thing would be a large undertaking though, even larger than rings or simple orbitals, and would be a ways off.
Would it be better to fix Earth and our handling of it before we attempted to move to another body? Not necessarily. If we spread the population out across multiple bodies, it would provide less stress on a single body and allow us to fix them individually more quickly than if we tried to fix one with a lot more stress on it. Let’s say we were on two planets and split the population across them evenly. That means half the carbon dioxide is being generated on each one than if we were on a single planet. Carbon dioxide is a greenhouse gas and cutting the production in half provides a lot more time to fix any issues. Moving to orbitals would help with that as well but only if we can work out the carbon imports and exports
Ensuring an orbital stays in its initial position is challenge enough, so adding/reducing mass to it may add further complications. Then there are other factors to consider like solar storms, meteors, interstellar radiation, and our very own space debris. To produce anything organic on it, temperature control is required, and is a challenge even on a “primitive” model such as the space station.
The depressing news on the space elevator is from Wikipedia:
Available materials are not strong and light enough to make an Earth space elevator practical. Some sources expect that future advances in carbon nanotubes (CNTs) could lead to a practical design. Other sources believe that CNTs will never be strong enough. Possible future alternatives include boron nitride nanotubes, diamond nanothreads and macro-scale single crystal graphene.
Having everything hydrogen fuelled for energy and heat would reduce waste a bit, the problem of waste disposal/exchange is, and will ever be costly and involved. Surely the garbots of tomorrow can come to the party as well! 🙂