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alexxerth t1_j5v9cbx wrote

I'm a little confused.

>Therefore, sending extremely compact, lightweight materials — like algae starts, mushroom spores, and thin plastic molds — that will then “grow” into significantly larger structures has tremendous appeal.

So where's the mass of the structure coming from then?

It's gotta come from somewhere. On earth there's an atmosphere that it can draw most of that from, but on the moon they'd have to bring that with them. It's compact, but the weight would be relatively similar to just bringing pre-grown mushroom bricks, no?

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LitLitten t1_j5vc1ix wrote

They do require C and N as macronutrients like plants, but this mainly comes from feeding on tree roots or directly off of organic matter. Plants are mostly an outlier in that their carbon is acquired through respiration.

Either way, you probably need a bit of mass as either soil or some other form of organic matter to feed fungus, which is probably heavy. There’s also the issue of providing them o2 and dealing with the co2 they emit.

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Cutecumber_Roll t1_j5ve9ma wrote

O2 is the easy part. Moon bases will have so much O2 they will be venting it into space as soon as they start making Aluminium.

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LitLitten t1_j5w9gk1 wrote

You sent me into an aluminum smelting rabbit hole — I had no idea one of the byproducts was oxygen. Super cool.

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[deleted] t1_j5wnkdb wrote

[deleted]

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TheHancock t1_j5xfy9h wrote

So what you’re saying is a moon base is going to tank the price of semiconductors? The RTX 6000 will be affordable!

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mrbibs350 t1_j5x7vkn wrote

Solar farm with a gravity battery? Would that be the best bet?

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MyWALife t1_j5xkmca wrote

Your gravity battery would have to be 6x the size of its equivalent on Earth. Think it would work?

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mrbibs350 t1_j62ii2t wrote

I think so....

Locate at one of the craters with permanent shadow where ice forms. Use excess energy to melt the ice and pump water to the top of the crater. Let it flow during lunar night to cover the lapse in solar power.

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The_Solar_Oracle t1_j5wznpu wrote

Separating aluminum from oxygen on the Moon in the first place is a little tricky

Unlike Earth, where most aluminum is recovered from bauxite using the Bayer process (producing alumina, or aluminum oxide) and then the Hall–Héroult process, aluminum on the Moon is overwhelmingly anorthite that cannot be processed in the same way.

Instead, more energy intensive methods must be used. Perhaps the most favored alternative is using the FFS Cambridge Process (typically used on titanium oxides), as detailed in Ellery et al.'s FFC Cambridge Process and Metallic 3d Printing for Deep In-Situ Resource Utilization - A Match Made on the Moon. Energy production may be an issue, especially if all the refining has to take place on the Moon, where nuclear power would have to employ enormous or very high output radiators to shed their waste heat and where Lunar nights can reduce Solar power input.

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CyberneticPanda t1_j5x135t wrote

With it's low gravity and lack of atmosphere, the moon screams for orbital solar.

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codesnik t1_j5yrj74 wrote

usable stable orbit with sufficient focusing would be, um, tricky.
I see nothing wrong with a factory which operates only for 2 weeks any month

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CyberneticPanda t1_j5zjimm wrote

The first ones will probably be set up at the south pole with solar panels on the rims of craters that get sunlight all year except during a lunar eclipse, but there are stable orbits at Lagrange points. Since the moon has no atmosphere microwave power transmission would be pretty effective.

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The_Solar_Oracle t1_j5zn0um wrote

While Solar Power Satellites for Earth are normally depicted as being used from a geostationary orbit, you can conceivably use them in other orbits provided you have at least two or three or so to provide continual coverage. Molniya orbits, for example, are a popular suggestion for Earth SPS to provide energy directly to higher latitudes.

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LitLitten t1_j60kx56 wrote

I wonder if inevitably the best approach will end up being taking advantage to some of the darkest craters and outfitting them as nuclear reactor heat sinks.

Could feasibly (?) bore a surface-subsurface tunnel for management from within the crater for necessary lab and maintenance habitation. Connect to other craters in this manner for production and so forth.

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codesnik t1_j643y7o wrote

I see zero reason to use darkest anything for heatsinks. You don't have (external) convection on the Moon, so you have a) radiation, b) direct heat transfer. Radiation doesn't care, just protect radiators from the incoming radiation. Just rotating radiators 90 to the sunlight direction into the sky is enough. Direct transfer would satiate stone around it pretty quickly even if it was in the dark for million of years. If you go under the surface with some kind of pipes, it again doesn't matter, if it's in a crater or on a moon plain on a moon noon.

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LitLitten t1_j647756 wrote

Ah my apologies.

I falsely assumed that the regolith of impact areas would be pliable enough to serve as a heat sink, but you’re right—sand, gravel et al. are awful conductors.

Are there feasible methods for keeping lunar dust from magnetically clumping to radiators? I recall it was a concern for grounded solar arrays.

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codesnik t1_j656mfa wrote

electrostatically, you probably mean? I have no idea, but I'd think that charging their surface with the same sign would work.

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HearTheRaven t1_j619trv wrote

> I see nothing wrong with a factory which operates only for 2 weeks any month

Do all the energy-intensive processing during the day

Do all the manpower intensive maintenance at night

Just a scheduling problem

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KenethSargatanas t1_j5w232a wrote

My guess is that they will extract it from lunar regolith. The Moon has all of the major elements of life just lying around. It true that it's not in the same proportions as Earth, and it will take time and effort to develop the processes to obtain and process them, but they are there.

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CyberneticPanda t1_j5x1f5l wrote

It doesn't have much hydrogen which you need to make water and hydrocarbons.

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KenethSargatanas t1_j5x2bc2 wrote

There is plenty locked up in the water ice we've detected in the polar craters. Simple electrolysis would produce more then enough hydrogen.

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