If humans are to colonize space, we will need large, human-rated structures to live in. It makes no sense to build an entire orbiting colony out of tin cans launched from Earth. Let's discuss some ideas for in-space construction to pave the way for human colonization of space!
Responses
Co-Founder, Space Cooperative
Kim Stanley Robinson's 2312
and James S.A. Corey's The Expanse
series both feature asteroids that are hollowed-out and spun-up to create habitats/spacecraft with artificial gravity. Seems like an efficient way to use mined-out asteroids.
I'm a fan of this style with one big caveat: all the loose material at the surface would just fly away at best, and at worst it may fracture under the stress.
Curious which will come first: asteroid mining or a lunar industrial base.
Technical Architect
The Expanse did trigger my imagination with regards to building in space. Elon is drilling tunnels under LA. Is he planning that as part of his Mars missions? If that can be pulled off, it could eliminate alot of the prefabrication that has to be done to create a livable space that will also shield inhabitants from the environment outside.
All that pulverized rock could also be reused for some type of purpose, either cement or maybe even to augment soil if it has the right mineral composition.
Software Development/Government Design
What if you could burrow under the ground in a way that didn't require a lot of support structures and then used a medium sized 3D printer to print out medium sized modular components that could be connected together to construct walls and ceilings that cover the rough tunnnel surface and ensure that the structure is airtight?
Space Architect
I'm not sure there are advantages to hollowing out asteroids to live in them! The amount of infrastructure work to be done would be huge (digging, shaping, pressure sealing, structuring, outfitting, running utilities...) why not do all that on an orbiting facility instead? The resulting station will be very functionally similar, with the added advantages of being able to move it, park it close to an asteroid, and mine it! I'm thinking of a way to use asteroid material (or regolith) compacted and packed into bags that could then be placed around the body of the station for radiation protection.
Concepts Development, Organisation, Operations Specialist
The intention is not to hollow out the asteroids in orde to live in them. Rather, it is to make use of the tunnels created from mining the asteroid. I suspect that this would be a temporary measure to provide increased habitation space for the workers conducting mining operations. Ideally, the entire asteroid will eventually be mined, making use of ALL the material resources. However, before the asteroid is completely mined, you might as well make use of the natural resource in order to make living there that much more comfortable.
Space Architect
Ok, viewing from this angle it does make a lot of sense! The challenge now is how to make an asteroid tunnel become habitable space?
Concepts Development, Organisation, Operations Specialist
This is not very difficult. All you really need to do is line the tunnel walls with a gas-impermeable layer (this could be as little as a few layers of plastic or synthetic rubber... similar to the shrink-wrap
material used to seal windows for improved isolation). Some ofthe mined material itself could be manufactured into bricks
to reinforce the tunnel walls, if necessary.
Space Architect
I agree, I think space mining will basically drive the space economy and human expansion! As happened throughout human history, the search for new, unexplored sources of riches will send pioneers as far as technologically feasible. With that, industrial colonies will be founded, establishing permanenttrade routes, which in turn incentivizes new waves of settlers in search of new opportunities. I just hope to live long enough to see that!
Technical Architect
I posted in another thread on this topic before seeing this post! Here's what I wrote on the topic.
I believe all the components are now available to create a space manufactory. The challenge becomes merging the components together to create a self-sustaining ecosystem.
Core technical components:
- Low-cost launch vehicle
- 3D-printers
- Drones and robotics
- Power to sustain operations
- Steady flow of raw materials
- Reusable, commodity building block designs
The overall theory here is to "seed" the initial platform, which builds a beachhead in space. The initial infrastructure serves to build even bigger infrastructure.
The idea here is to lower costs and risks by using off the shelf components and eventually building economies of scale. Big bang launches can be extremely expensive , risky, and time consuming.
Ideally, a fully operational space could be built before a human ever steps foot inside of the manufactory.
Overall, once the equipment is up and running, only raw materials are then being shipped up to the manufactory. Very long term, the materials will be sourced from asteroids and space, relieving the effort of having to build launch vehicles fighting against trying to escape the atmosphere.
See Von Neumann probes for an overall vision and its variants:
https://en.wikipedia.org/wiki/Self-replicating_spacecraft
As the mission description notes, garage tech can complement the existing platforms by reducing costs. Obviously there is also alot of regulatory work that needs to be done to make sure these platforms can be achieved.
Some resources for further diligence:
- Rockoon small payload launches: https://www.leoaerospace.com/
- 3D printing: https://www.carbon3d.com/
Space Architect
Yes, if we could build a first shipyard
in space it would highly increase the capabilities of manufacturing and launching larger and better spacecrafts, not limited by payload fairing dimensions and lift capacity. A great challenge is the ability to process and use these materials in the micro-G, vaccuum condition of space. How could we get past this?
Concepts Development, Organisation, Operations Specialist
A shipyard in space is a good start. However, just as important, IMOH, is the establishment of off-planet (off Earth) mining resources, and processing. Shipping materials from lunar surface to low EARTH orbit requires no more energy than shipping from Earth surface to LEO. Shipping from LS to higher orbits require far fewer resources. Our objective should be an early push to establish a permanent lunar operation... although this would be paid for by Earth orbit operations, through bootstrapping
.
Space Architect
By the way, this is wild, I love it! Great topic for a sci-fi book.
[ self-replicating machines launched by different species might actually compete with one another (in a Darwinistic fashion) for raw material, or even have conflicting missions. Given enough variety of species
they might even form a type of ecology, or – should they also have a form of artificial intelligence – a society. They may even mutate with untold thousands of generations
.]
Concepts Development, Organisation, Operations Specialist
One means of reducing launch costs is by converting the launch vehicle itself into payload. Skylab has proven that propellant pressure hulls can easily be converted into pressurised habitats. Clusters of thrusters, and associated thrust assembly structures, could either be staged (dropped when no longer necessary) for later reuse, or they (the ones appropriately rated for vacuum use) could be repurposed for space travel. The fairings could be designed for reentry, as reusable vehicles; and the intertank structures could be used as support walls to shore up mining shafts.
This is a project I have actually been developing for some time, now.
Concepts Development, Organisation, Operations Specialist
I would point out that the seeding
principal here actually makes a fairly strong argument for modular design. The modules (which can be constructed on Earth OR on the moon (or elsewhere), would be able to go into immediate service, supprting the infrastructural needs of further development. of course, there is no reason why ALL construction would have to be modular, but modular construction allows for a strong start.
Technical Architect
Elon Musk's Tweet today:
High altitude wind shear data shows a probable 2% load exceedance. Small, but better to be paranoid. Postponing launch to tomorrow, assuming winds are better then.
Seems like getting vehicles built outside of the atmosphere is a mandatory step for any large-scale buildout !
L5 The First City in Space is a Kennedy Space Center IMAX movie showcasing life aboard a gigantic rotating spacestation.
Babylon 5 was a TV series that also depicted life ,albeit action packed, existing aboard an enormous hollow space habitat.
I agree with Suzana on this.
Our next most immediate concern is to nurture hope in humanity through enthusiastic possibility.
And the best way to do that is to build momentum through audience interest.
And fewer things exist in all of creation to excite the heart through the mind's imagination than that of the thought of somehow being able to build impossibly great huge gynormous orbiting space complexes habitats cities even metropolitans environments and actually whole (including exo zeno ?) interior planetary ecosystems.
In other words: great space flying super mega structures!
Something that people can invest in. Something we can explore grow research and develop build on in.
So I propose that we first & foremost ,before anything else, create a video film like L5 The First Spacecity of what it would be like to live work research science engineer develop and especially play and work around in such a ,multisized (for different gravities) cylinders, spaceisland .
Babylon 6 anyone ?
And to develop a game ,actually really just a simple sim, of its (including giant florescent mushrooms?) interiors to go along with the video.
This way people can get some idea fore-th a feel for the total jumping awesomeness of what its like to be able to bound around in a fifth of one Earth 'G'.
WOO HA !
P.S.
Scratch the idea about making the video and the Sim as two separate experiences.
Instead, make it a ,personed, tour video of the 360°(including VR?) station Sim environment.
have it with limited functionality ,user interactiveness, for simplicity.
In other words just have it as a multimedia like video but with a bit of interactiveness thrown in for imagination stimulation possibility.
I guess what I'm trying to say is previsualize it as another (upgraded?) L5 like spacecity showcase film.
But instead of having an asteroid collision emergency as a plot instead, have merely a guest walkingtour of science engineering research development projects going on at the station. Like the kind of visitors tours that various kinds of technology centres (including NASA) provide to families to the public.
Concepts Development, Organisation, Operations Specialist
I don't know much about sims, and am not great at processing video... but I could probably put together a Babylon 6
design for you! I have a fairly good idea about how it could be constructed.
Software Development/Government Design
What if a Mars crew had a temporary inflatable structure and a burrowing machine? They could inflate the structure when they first arrive for a simple habitat and then when the ground was burrowed out they could deflate the structure and lower it into the burrow where it would act as an airtight liner. Then modules could be printed out with a medium sized 3D printer for covering the ceiling, floor, and walls. Two layer skylight style windows could be made looking out through the surface. The windows could be filled with gas that blocks cosmic rays.
Concepts Development, Organisation, Operations Specialist
The only downsides to an inflatable structure would be the radiation exposure while above ground, and the possibility of damage from sandstorm activity (even if it is not as energetic as depicted in The Martian
. Nothing unsolvable.
Space Architect
Yes, inflatables can seem a bit more prone to wear and tear, but the material they are made of is quite strong! But I was thinking up some ideas for a self healing inflatable habitat, I wonder if it is possible....
Concepts Development, Organisation, Operations Specialist
Indeed. In fact, some material available for inflatable structures are more resistant to wear than solid metals. It depends, however, on what materials are chosen (I listed the possibility in the event of going with the cheapest solution, rather than the most cost effective).
There are actually a number of possibilities for self-healing structures, whether rigid or inflatable.
One common strategy is multi-layer reactants that are normally separated, but form a strong seal when they combine (through a penetration). The down side is that the reactants can leak out penetrations on sides where there is nothing to combine with... and, once combined, the reactants are not normally resupplied; so, in both cases, there is the weakness that this method will only work for a very few number of events. Another downside is potential toxicity.
Likewise, you could have single reactants that simply react to atmospheric contact. This could be tricky, as there is no guarantee that the reaction would actually seal the rupture, instead of the flow of the compound to the rupture.
For inflatable designs, one idea I had involves a new material that was developed a few years ago... I don't know if it ever went into production. The material was a self sealing elastic. The nature of the material was such that ruptured ends only needed to be pushed together to reform a bond that was almost as strong as the original, and also nearly as elastic. For our purposes, we probably won't want to use the elastic properties, but the bonding properties would be quite useful.
Another option would be filling layers with high-viscosity gels or fluids. So long as the substance is liquid enough to flow, the viscosity should create enough surface tension to seal any small penetration. Again, a possible downside would be toxicity, so the substance would have to be carefully chosen.
Space Architect
Another option would be filling layers with high-viscosity gels or fluids. So long as the substance is liquid enough to flow, the viscosity should create enough surface tension to seal any small penetration. Again, a possible downside would be toxicity, so the substance would have to be carefully chosen.
this is exactly what I have been thinking of!
Concepts Development, Organisation, Operations Specialist
Along these lines, you would probably want a very thin layer (or perhaps sets of branching tubes) to induce a capillary action. The hard part would be finding a material that has enough viscosity that it seals the hole without bleeding
(especially against a large pressure differential), but fluid enough to flow into the hole in the first place.
Concepts Development, Organisation, Operations Specialist
Returning to the issue of strength
... factors regarding material strength are actually rather complicated, and chosing a material can be VERY important. For example, Kevlar has quite admirable properties, compared with metals. It has much stronger tensile strength than most, if not all, metals (it will not easily rupture from overinflation); and has roughly comparable compressive strength (it will not crumble or sag under a heavy weight). However, it is EXTREMELY easy to cut (it can quite literally be cut with a butter-knife). This means that you would NOT want to use kevlar as the outer shell for an inflatable shelter on Mars, as strong winds could easily cause abrasian damage by causing it to rub against a sufficiently sharp rock.
That said, you could use a woven-metal cloth as a shell. This is not strong enough to support its own weight, nor to resist high pressure differentials, but it is excellent against cuts and punctures. This would allow Kevlar to be used as a pressure resistent liner.
Space Architect
Yes, I've been looking into basalt fiber fabrics or meshes for an external layer... This site has many interesting uses for basalt which is significantly present on the moon and Mars. http://www.basaltft.com/index.htm
Space Architect
I agree Luis, there is so much available material up there! Perhaps we should design a scavaging mission?
Concepts Development, Organisation, Operations Specialist
It might not be necessary to expend the propellant necessary to relocate salvage to a Lagrange point. Instead we install a small (but expandable) orbital station that will collect and work on the scrap
directly.
This station would be composed of a centrifugal habitat space, with a central hub fitted with a kind of wet-dock
that salvage can be moored to. The habitat would be composed of the propellant tank modules, wet launched
with only engine clusters being staged. The shroud would carry all the equipment and supplies necessary for stocking the habitat, as well as any additional structural elements.
A single launch of a rocket about the size of a Saturn V derivative would be sufficient for establishing the station. Future launches would expand the operational platform.
