[Space] What’s the minimum resources required for Asteroid or Comet habitats?
 

While the setting is TL9 in general but TL10 in Computing (except AI), Biotech and Fusion, I’m more interested in what’s required given our current tech and likely advancements in the next few decades. Assume that human health issues in low-gravity environments is not an issue.

What kind of raw resources are required to build and maintain beehive colonies?

What kind of industrial ores are needed? Can you get by with just Iron/Nickel, or perhaps just Carbon?
What about electronics? Will Platinum suffice?

What’s needed for lifesupport? Obviously Water Ice takes care of water and air requirements (using 1/3 pressure pure oxygen mix + a bit of water vapor). But what’s needed for food, assuming hydroponics? Nitrate and carbon I imagine, but what else? What minerals are vital for human health? And what compounds found in asteroids or comets are likely to contain these minerals, and how abundant are they?

Basically, what’s the shopping list for asteroid/comet miners that are supporting a colony, and in what quantities. What likely compounds will be looked for an exploited?

Thanks in advance,
Trachmyr

Re: [Space] What’s the minimum resources required for Asteroid or Comet habitats?
 

You're going to be needing both, and other stuff too.

For ex, you'll almost surely need a metallic electrical conductor, silver, gold, copper, or aluminum are all candidates (other possibilities exist), and all are likely to be available in the asteroids. KBOs and comets are iffier.

For another example, if you want solid-state electronics, you need silicon, which probably isn't a problem on the asteroids, but might be on a comet. Other substrate options exist, but silicon is convenient, we know a lot about how to deal with it and use it, and it's pretty common in the universe. It also makes photovoltaic panels easier if you've got silicon.

Also, most of the current lithography techniques involve some pretty sophisticated chemistry. I don't know everything required, but IIANM manufactuing PV panels, for ex, often involves fluorine.

Often there are many ways a product can be made, though. The point is that you're going to need a lot of things that won't be obvious and might be necessary only in small amounts, but will be absolutely necessary even so.

You're going to need an energy source, which is a more complicated issue that it looks. The further from the Sun you are, obviously, the less useful solar panels are, and it falls off fast once you get past the orbit of Jupiter. So the further out you're planning to be, the more appealing nuclear power looks. Are we assuming fusion power? If so, can we burn protium or do we need deuterium or tritium?

Absent fusion, fission can certainly work, but fissionables might be hard to get in those parts of the Solar System where they would be most needed, out past the snowline. Note that you can use solar power in the outer Solar System, it's just harder and more expensive. With a decent sized KBO or asteroid, enormous solar panels would be possible...if you can afford them in terms of money or resources.

The thing is that there are a lot of question marks about cometary composition. A lot of them may have metal/stony cores, but then again, metals may well be at a premium on comets, either because the core is mostly frozen volatiles, or because the metals are buried deep under a layer of thick ice.

Not alone. You're going to need insulators, semiconductors, etc. Plus the supporting technological infrastructure to make and maintain them.

Also, regarding metals, you're going to need concentrated energy sources to mine and refine the metals, even on an asteroid. Separating aluminum from its common oxides, for ex, is a bitch, it takes a lot of energy. You'll likely have to grind up large amounts of rock, which takes more energy, you'll have to heat rock, expose it to chemicals, etc.

Just how self-sufficient is this habitat supposed to be?

What are you using for the buffer? Nitrogen is probably, or at least plausibly, available on KBOs, but it might be at a premium on stony-iron asteroids. I suspect there would be major problems with using hydrox long-term, medical and safety-wise, and hydrogen is the only other gas water will give you.

Iron, phosphorus, calcium, copper, magnesium, sodium, and zinc at least, off the top of my head.

You'll also need plenty of carbon, nitrogen, oxygen, and hydrogen, in the appropriate forms, to provide the bulk material for your internal food supply as it cycles back and forth. So here again, even if you don't use nitrogen as your air buffer, you'll need nitrogen to survive.

Note too that hydroponics can dispense with soil, but the plants still have to have light. If you're close enough, you can use direct sunlight through some kind of transparent material, just like on Earth (but keep in mind the radiation shielding effects of Earth's atmosphere). If you're further out, mirrors can concentrate sunlight, or you can use artificial light...but be warned that this last option is power-intensive.

You're going to have to recycle the air and water, of course. In theory this can be done with a proper balance of plants and people...but see Biosphere II for the actual state of the art on that.

Re: [Space] What’s the minimum resources required for Asteroid or Comet habitats?
 

Thanks for your response... it is much appreciated.

BTW, as to why I need a shopping list... my PC's are considering going into the surveying/mining trade, and I need to know what's valuable and what's garbage in this kind of environment.


As to some of your questions:

Energy will be produced by Deuterium Fusion (with tritium secondary reactions). Fusion based tech is one of the advanced areas for this setting. The fuel is proccessed from water ice, while not as abundant as seawater, it should still have similar abundancy as found in jupiter... about 22 atoms per million. The reactor core is the heart of each colony.

Each colony is not self-sufficent in and of itself, though through recycling, they can maintain themselves for decent spans of time. There are however hundreds of colonies, each with specific imports/exports. The setting takes place around Alpha Centauri, both stars have substantial asteroid belts in their outer orbits. Those around Alpha Centauri A lie within the snow-line, those around B lie beyond the snow line. Colonies begin as mining colonies, extracting ores, minerals or volatiles to support the larger permanent colonies. Eventually a mining colony is either abandoned, or settled on a permanent basis, where it begins to focus on manufacturing/biotech (including food production)/R&D. The colonies form a large interdependant web, where sel-suficiency occurs at the Macro-level of the totality of the colonies. This breeds a setting where the PC can be mobile, and elements such as private tramps, pirates and a civilian patrol are possible.

As for the air mix, I'm using what space-suits use: Total pressure of 32.4 kPa, equal to the 20.7 kPa partial pressure of oxygen in the Earth's atmosphere at sea level, plus 5.3 kPa CO2 (exhaled) and 6.3 kPa water vapor..
Thus no Nitrogen.


Hydroponics will be using artifical light... while power-intensive, Fusion power rather than solar power should meet the requirements.

While recycling is important, I actually think that as for O2, high efficiency is not too critical. The reason is that a lot of Water Ice is mined, used primarily as reaction mass. While many "short-run" vessels use water as reaction mass, there are many that use Hydrogen.... that leaves a lot of O2 leftover (millions of tons a year), although it is also used as reaction mass (4x thrust and 1/4th Delta-V).

------------

Thanks again,
Trachmyr

Re: [Space] What’s the minimum resources required for Asteroid or Comet habitats?
 

My primary concern with that method would be that you're constantly increasing the atmospheric mass inside the habitats and tying up a lot of carbon in the air.

You are also going to find the CO2 content of the atmospheres in the habitats quickly exceeding tolerable levels. Unless you just vent all that CO2 into space (or use it for fuel) in which case you're wasting that carbon.

Since you mentioned bio-tech TL10 I'd just go with large mirrors focusing solar light onto gengineered plants for the CO2->O2 process.

I honestly don't know how rare carbon is in asteroids or comets but if you're giving them bio-tech at TL+1 then they really shouldn't be wasting it.

Re: [Space] What’s the minimum resources required for Asteroid or Comet habitats?
 

Ah!

I figure that chalcophile elements are going to be scarce in space. Siderophiles ought to be found in the nickel-iron material, lithophiles in the stony asteroids, and atmophiles in the ices. But I don't know of any material in space that is enriched with chalcophiles to anything like the richness of a commercial ore. The material simply isn't differentiated enough.

Sulphur itself probably isn't terribly scarce, but silver, arsenic, bismuth, cadmium, copper, gallium, germanium, mercury, indium, lead, polonium, antimony, selenium, tin, tellurium, tantalum, and zinc probably only exist in ores about as rich as concrete.

Also, don't be too blasé about, for instance, the platinums. Iron-type asteroids are platinum-rich compared with the Earth's crust average, but not as rich as a good commercial ore.

Re: [Space] What’s the minimum resources required for Asteroid or Comet habitats?
 

I think Trachmyr is thinking of using the O2 excess to replace loss through leaks.

Not if you fix the carbon using plant growth and just vent the oxygen. But I'm a little puzzled as to why you figure that CO2 content in the air is going to rise.
Not terribly rare. There is bulk carbon monoxide, carbon dioxide, methane methanol, formaldeyde, ethanol, ethane, and hydrogen cyanide in comets, and the surface of a comet's nucleus seems to be covered with an organic layer like tar or crude oil. Besides that about 5% of meteoritic material is carbonaceous chondrite, so presumably a significant proportion of asteroids are too (including, probably, a significant amount of the surfaces of Phobos and Ceres). Carbonaceous chondrites range from about 0.3% to 2% carbon by mass. Not a great source. But at least it is plentiful.

Re: [Space] What’s the minimum resources required for Asteroid or Comet habitats?
 

I'm amazed that that is viable ... I thought CO2 was that which triggered the exhale reflex, and did so at a fairly low percentage content, although it's been a while since I did any physiology.

TL is probably going to be important as well - nanotech assemblers or replicators are going to make self sufficiency a lot easier than TL8-9 tech, and superscience power generation like zero point energy or a singularity core will make the energy problem go away as well.

Apart from that, why am I getting sudden visions of Dwarf Fortress ... In Space!

Re: [Space] What’s the minimum resources required for Asteroid or Comet habitats?
 

That is indeed true. In fact, we tolerate a decrease in oxygen by, say, 50% better than we tolerate 50% more CO2 in the air.

Re: [Space] What’s the minimum resources required for Asteroid or Comet habitats?
 

Again, I really appreciate your feedback.

-------------------

As to the breathing gas... I pulled the composition off wiki, and verified it on some of NASA's pages. But your right, the CO2 content seems very high. But the CO2 is not added to the mix, instead, the mix takes into account the partial pressure of exhaled CO2 to make sure the partial pressure of O2 remains similar to sea-level partial pressures on Earth.

But with that said... I do believe I made a mistake. The space suit mix assumes very tight quarters, and for short durations. Within a colony, the CO2 level should be significantly lower... thus the air mix will be at even lower overall pressure, as the CO2 level is reduced.

Something more akin to: Total pressure of 25.0 kPa, equal to the 20.7 kPa partial pressure of oxygen in the Earth's atmosphere at sea level, plus 0.2 kPa CO2 (exhaled) and 4.1 kPa water vapor.

And yes, I did mean to use surplus O2 to make up for leaks in the system (especially for mining colonies where loss will occur in shafts through bare rock). High CO2 concentrations could also be flushed and replaced on colonies that lack hydroponics, but you're right... that does seem like a big waste of Carbon (if carbon is at all scarce).

--------------------------

As for the TL... while more prosperous colonies can surely make use of high tech improvements, my concern is the cost-conscious frontier colonies that effectively run on TL8/9 local facilities... while they can import more advanced and expensive facilities, it cuts strongly into profits. The idea is that a small group of moderately wealthy individuals (with a few loans) can start up a mining colony on their own... perhaps with successful planning and a bit of luck, turn that mining colony into a settled colony in a few decades time. A bit of the "Firefly" mentality, but without the overt western trappings.

----------------

@ Brett: As always, I appreciate your response and details given. You deffinately pointed me in the right direction.

A couple of follow-ups:

1) I've already stated that water and methane ices are common (methane is used for extraction and production of organics), but how common would Ammonia Ice be? If helpful the star is K1V, Luminosity 0.50, and the belt extends to 3.83 AU, 0.4AU past the snowline. If present, would it be possible to extract the Nitrogen from Ammonia Ice?

2) How plausible is it to streamline industry to use only more abundant elements, at least for most mass production. The products of the colonies have already been described as boxy, bulky and heavier than normal but also more rugged. It's function over form to the extreme (well kinda, most items have dozens of VR skin that can be downloaded to them).

3) How will focusing on industry and lifesupport to the absence of commerical and recreational facilities/products affect the need for certain resources. Obviously, in a non-consumer market, quantity is heavily reduced, but what resources (if any) become less important. The reason is heavily intergrated AR/VR; stores, malls, resturants, clubs, parks, rollercoasters, door-knobs, your TV, posters/pictures, knick-knacks/collectibiles, non-protective clothing, etc. all exist as VR objects only... interacted with in either AR or VR.

Re: [Space] What’s the minimum resources required for Asteroid or Comet habitats?
 

Ok. Yes, it's partial pressures that's really important.