The Moon Society Forum

Well, let's start with the obvious. Early bases will rely on upported food, mostly freeze dried and dehydrated, and probably recycled water. Oxygen will be recycled with chemical systems that decompose CO2. Rocket fuel and oxidizer for return to Earth will be upported rather than risking the failure of propellant production systems on the Moon and becoming stranded. At least this is the impression I am getting in connection with NASA's RTM program.

How do we get beyond this? I would suggest using robots to pave the way for a permanent human presence on the Moon. Job one would be regolith mining and oxygen production. I favor the use of molten silicate electrolysis for oxygen production, although ilmenite reduction with hydrogen or vapor pyrolysis might be used instead. Down here at the Moon Society St. Louis chapter most of us have focused on molten silicate electrolysis, also called magma electrolysis, partly because some of us met the late Dr. Larry Haskin from Washington University and he did lots of research on this. Oxygen would be used for return to Earth as well as replacing leakage losses in LSS and for fuel cell reactant. We would also need O2 liquiefying, storage and pumping equipment.

The next job, that could also be done concurrently with robotic regolith mining and LOX production would be solar wind implanted volatiles harvesting with a device like Kulcinski's ten ton Mark 3 miner that could produce about 200 tons of H2/yr., 16.5 tons N2, 80 tons carbon in the form of CH4, CO2 and CO, and some helium. Naturally, we'd need liquefying, storage and pumping gear for these too. That 200 tons of H2 could make 1800 tons of water if combined with O2 in fuel cells and if we run a 6:1 O2/H2 ratio as in the Shuttle we could make a total of 1400 tons of rocket propellant. That's nothing to sneeze at!

None of this could be done without energy, so if we want to get more nitty gritty the really first thing we'd have to do is deploy solar panels, fuel cell systems for nightspan, and possibly a small nuclear powerplant.

Just getting this basic set up for producing oxygen, hydrogen, water, nitrogen, carbon, and helium along with storage and pumping systems would involve landing some respectable tonnages of equipment probably in modular form all ready to go without doing to many complex tasks with the teleoperated robots. I'll let others make guesstimates on the mass, cost and number of people we could support.

It costs about $10,000/lb. to orbit a payload with the Shuttle. The Apollo system cost about $30,000/lb. to the Moon. I don't think we should use either of these as benchmarks. The Delta rockets can place payloads in LEO for about $3,000/lb. and the Russians can do it cheaper than that. Space X Falcon rockets should be able to do this for about $1,500/lb. Correct me if I am wrong. That's one reason we have discussions. We all make mistakes. So let's just guess that in the near future we could put cargo on the Moon for $10,000/lb. At that price, 200 tons of hydrogen would be worth $4 billion!

So we operate this robotic equipment for some time to test it out, make sure it is reliable, work out the bugs, store up some gases and liquids and make sure nothing leaks. We could send up some unmanned probes, roll out some rovers and do some prospecting, then fuel up the return vehicle and send several hundred pounds of samples back to Earth to prove out the system.

All this equipment must work for years and endure thermal cycling and we must have back-ups. Once we feel secure with the system we start sending up humans and inflating habitat with LUNOX and N2, fueling up fuel cells with lunar derived H2 and O2, producing water for humans and gardens, storing up rocket propellants for return flight, and starting up gardens in inflated habitat. We will use some of that CO2 that forms due to the reaction of solar wind carbon atoms with oxygen in regolith when we roast it out at about 700 C. for our garden modules. Hopefully we will be able to grow meat in petri dishes. We will get in some harvests before our dried food stocks run out and store up the food by canning and freezing it. Perhaps simple holes dug in the ground will allow us to take advantage of the sub surface minus 20 C or minus 4 F to keep food containers cold.

We will probably need to fertilize the regolith before we start planting in it. We might steam it to form vermiculites and we will innoculate it with microbes that break down minerals and make nutrients bioavailable to the crops roots. We will need waste recycling systems to return nutrients to the gardens. And we will need fuel cell systems and red and blue LEDs to illuminate the crops during nightspan.

How much garden space will we need? It depends on how many people we want to support. What will be the mass of the inflatables and hard modules we put down on the surface?

Before I close, let me add these ideas. Perhaps we will want expand in anticipation of large crews. Could we make glass fiber cloth on the Moon and seal it with silicones made on the Moon to make inflatable hab and garden modules on the Moon? Will be able to establish a closed ecological life support system that only requires minor additions of water and CO2 to replace leakage? Let's hope so.

What about cannibalizing landers? Most of the robotic cargos are going to make a one way trip to the Moon. We could cut up the fuel tanks with lasers or electric arcs to get metals and lightweight composite tanks could be cut up with saws to get those epoxies, Kevlar, carbon-carbon, etc. they are made of and grind them up and roast them in solar furnaces to break them down into carbon, hydrogen and nitrogen. Also, some lander tanks could be used for storage of gases and liquids produced on the Moon or even be coverted to habitat or vehicle cabins.

So these are our first tasks on the way to cutting the umbilical cord to Earth. While we might not get 100% self sufficiency we will be able to minimize the amount of payload needed from Earth and save billions of dollars.

Most of these concepts are familiar to space enthusiasts. Like i said, let's start with the obvious. In the future of this discussion lets try to come up with new and novel ideas. I haven't said anything yet about materials production and manufacturing on the Moon. Once we are producing materials and making all our storage tanks, piping systems, radiators, pumps, compressors, electric motors, habitat modules and garden modules, vehicles, mining robots, etc. we can really reduce the amount of cargo we need to send to the Moon to expand the base and eventuallly reach a time when we are building mass drivers and launching metals and finished parts into space for powersat construction!

So, we want a Moon base with minimal resupply from Earth; hence the reliance on ISRU and bootstrapping. Eventually we will tap the resources of NEOs and Mars along with its moonlets and our reliance on Earth for anything besides dollars will be about zero. At first we will upport complex, lightwt and electronic items but eventually we will make our electronics on the Moon.

In the previous post I discussed oxygen and volatiles-H, He, N and C.

We can produce cast basalt, glass and GGCs, cement, plaster, iron, magnesium and sulfur on the Moon w/o upported chemical reagents. For more info see: http://www.moonminer.com/Moondust_index.html

http://www.moonminer.com/Recent-Documents.html

http://www.moonminer.com/Lunar-Manufacturing-Index.html

Titanium and aluminum will require chloride fluxes. CaCl2 for Ti refining FFC cells and LiCl and NaCl for Al production by the ALCOA process. see: http://www.nas.nasa.gov/About/Education ... s/V-5.html

quote: Two typical compositions of the electrolyte (in weight percent) are: AlCl3(5), NaCl(53), LiCl(40), MgCl2(0.5), KCl(O.5), and CaCl2(1); and AlCl3(5 ± 2), NaCl(53), and LiCl(42 ± 2). The aluminum chloride concentration must be carefully controlled to ensure trouble-free operation.
An operating life of nearly 3 years is claimed for the electrodes when the oxide content of the electrolyte remains below 0.03 weight percent. The energy consumption of the cell is 9 kWhr/kg of aluminum produced.

We will also need graphite electrodes for both FFC cells and Al electrolysis. Since graphite electrodes are made of carbon powder bonded with pitch, we will have to upport at first and eventually produce pitch on the Moon with some organic chemist's magic from C, H and N. So we will have to mine plenty of solar wind implanted carbon.

Chlorine is not abundant on the Moon, niether is lithium. We will have to upport LiCl in salt form. We could extract sodium from regolith and combine it with Cl upported in the form of copper or zinc chloride salts that we decompose on the Moon to get Cl and some Zn and Cu too. Plastic bags of salts might amass less than heavy insulated tanks of liquid chlorine.

While I don't know of a lunar lithium source, we could someday tap Cl from volcanic glass. From19.5 million tons of volcanic glass, that's in the range of regolith mining shemes proposed for mining volatiles, iron fines, etc. We'd get 1.1 million tons of oxygen; 8,800 tons of sulfur; 5,800 tons of zinc; 1,900 tons of chlorine; 1,900 tons of iron; 1,500 tons of nickel, 510 tons of copper, 310 tons of gallium.

http://www.moonminer.com/Lunar_Volcanic_Glass.html

Chlorine is also used to synthesize silicones and produce silane and in some silicon purification processes. It's pretty useful stuff. We need to make table salt too. So we will be upporting Cl salts at first and eventually mine volcanic glass to cut this particular cord with Earth.

Since titanium has excellent chloride corrosion resistance we should make Cl handling equipment (piping, pumps, valves, etc.) out of titanium.

About Carbon

Solar wind implanted carbon reacts with oxygen in the reg to form CO and CO2. It reacts with some of the H2 to form CH4. We could separate these with various methods like membranes, pressure swing absorption or cryonics. The CO2 is just fine as is for biospherics. CO+ CO ==> CO2 + C So we can convert CO to CO2 and carbon. Carbon will be useful for water filters perhaps, silicone synthesis and steel making. Some people think there is no carbon on the Moon for steel. Actually there is, just not a lot of it. Fortunately we don't need lots of carbon to make steel and we can use other metals on the Moon like iron, magnesium and titanium. One ton of C can make 100 tons of 1% high carbon steel. We'd combine the Fe and C by the now outdated blister or cementation process. That 100 tons of steel would make plenty of hi strength nuts and bolts, and we will want strong fasteners.

CO2 is a very stable molecule and it is hard to decompose with heat. Electrolysis just yields CO and Ox. So the std. procedure is to combine it with H2 to form CH4 and H2O. CH4 is decomposed to C and the H2 recovered at 900 C. The H2O is electrolyzed to recover H2 and gain Ox. Dr. R. Zubrin's book The Case for Mars gives a very detailed expanation of this chemistry.

About Machine Tools

At first, precision machine tools for work done by humans and robots will be upported. This could involve some large masses. What we will want to do is use machine tools to make machine tools from on site metals. As one engineer said at a recent Moon Society St. Louis chapter meeting, we could upport the precision motors and make the heavy base for a lathe, for instance, from lunar iron mined, refined and cast on the Moon. We will make use of the MUS/cle strategy to be sure. To really build a base with minimal support from Earth we must make our machines on the Moon and make spare parts for them too. Some parts like cutting blades and drill bits are going to wear out regularly. We will need cobalt steel for some of those drill bits. Fortunately, although cobalt is really rare, it isn't to tough to get. We mine iron fines with low intensity magnetic separaters and these fines contain 5% Ni and 0.2% Co that can be separated by treating the fines with hi press hot CO gas to form carbonyls that are distilled to sep them then decomposed with heat. At a recent meeting a veteran machinist said vanadium was just as good as cobalt, but this element is present only at about 100 ppm and there's no neat trick for getting it as there is with cobalt. However, bioleaching of trace elements on the Moon is always a possibility.

Anyhow, we want to get to the point where we are not just upporting the precision motors for machine tools on the Moon but making them on the Moon. Another veteran engineer at the MSSL chapter once said you can make a crude tool and use it to make a finer tool and after about four generations you have a high precision tool. So I wouldn't be surprised if we find ourselves making some machines that look like they came from the 19th century or a blacksmith's shop at first, but those crude machines can evolve into ultra fine machines.

some links to pages about materials extraction on the Moon:

http://www.nas.nasa.gov/About/Education ... s/V-5.html

http://www.nss.org/settlement/nasa/spac ... 3/toc.html

http://ads.harvard.edu/books/lbsa/

http://www.lpi.usra.edu/lunar_resources ... ofmoon.pdf

http://www.highfrontier.org/Archive/Jt/ ... 202015.pdf

http://fti.neep.wisc.edu/neep533/FALL2001/neep533.html


some of these processes are early proposals and are quite complex compared to later work

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I haven't really been participating, mostly because I've just been feeling lazy. But this is good stuff. It's an interesting question; if you are able to land 6 40-ton cargo pods on the moon to begin your lunar settlement [round figures; assuming a Saturn V-class booster, a one-way trip, and just enough fuel fraction for powered descent], what essentials would you pack in those six pods to allow you to bootstrap a functional and open-ended colony?

First priorities: Minimize consumables wastage. Water/waste/air recycling equipment. If you can produce some of your own food, even better.

Second: Low-hanging fruit. Equipment to process and recover lunar oxygen and, hopefully, in so doing to refine useable metals. Solar mirrors. Equipment for sintering regolith into usable "lunarcrete" structures.

Third: Shaping and extending your environment. Machine tools. Casting and rolling mills. Welding equipment. Wire-drawing, insulating, and motor-winding equipment.

I know I'm leaving out a lot of stuff. What can you think of?

This is an area wide open for brainstorming. If we can come up with lists of equipment and masses of those devices then work on lightening them with special materials, making them with on site materials all or in part, getting rid of anything unecessary and using miniturization we can reduce the mass and cost. The devices will have to be "replicatable" and "Moon makeable" and miniture devices could be "grown" into larger devices.

We will have to work out a process order. Going all the way back to step zero we need low cost launchers and I am hoping Space X and its Falcon launcers and descendants solve that problem. And hopefully Bigelow Aerospace and its inflatable space stations will create LEO tourism and industry to help things on their way. We will also need ion drives to move loads from LEO to LLO. What would really help is a beanstalk from L1 to the lunar surface.

After step zero, step one will be landing some low mass stretched array solar panels because nothing is going to happen without electricity! Next, I don't know...we must brainstorm. We might want to make cement first and that means mining tractors and furnaces as well as volatiles mining to get some water. Then we might print up some cement modules and bury them.

I did some thinking about this at http://www.moonminer.com/Lunar_Industrial_Seed.html But I want to modify that article because i think it would be better to get SiO2 by roasting regolith rather than H2SO4 leaching and I want to add some about contour crafting.

I think we will make use of CVD-chemical vapor deposition- using carbonyls of iron and maybe vaporized magnesium or aluminum. We could use stereolithography also called 3D sintering to make all sorts of parts and then assemble them with robots or humans. The average industrial robot has like 2000 parts! The Ford Model T had like 5000 parts! The challenges of making anything on the Moon are great indeed. While 3D printing is great technology, i think we are still going to have to do some standard casting and machining as per your post.

This is a challenge that will be surmounted in reality by teams of well paid engineers in the future. Man, I'd love to see the lists of machines they plan to use and how they plan to use them to replicate and grow a mininmal industrial seed mass on the Moon into major industry! But we can use our imaginations and brainstorm away in the meantime.

The other thing we need to do is convince the powers-that-be that we must return to the Moon for the purpose of SPS, possibly he3, asteroid deflection, pure science, tourism, and eventually terraforming Mars and beyond; but that's all politics and organization and I have no talent in those arenas. If we can just put together a picture of the "HOW" then maybe "they" will beleive the "WHYs" we propose are not just pie in the sky.

Hmmm. I've been wondering about what the lowest mass a Lunar colony seed would have to be. One idea I've been playing with is converting the TLI stage into a reusable transfer Shuttle. It might be as simple as a foldout solar array and a VASIMR that runs on oxygen, plus conversion of one of the fuel tanks (probably the LH2 one, if it uses Hydrogen) into a Habitat/Cargo space. If we have that, we can use Lunar oxygen for it's propulsion and reduce the cost of upporting from Terra to just a little over however much it costs to launch into LEO. If we have more than one launch (which we most likely will be using), we can strap them together and use some for fuel storage (depots, remember). It should be possible to use the engines on the descent craft for TLI, if we put it behind the upper stage. I have no idea how much the equipment required for conversion would mass, however.

So, we have a reusable Lunar shuttle, composed of the converted upper stages. Now to turn our attention on the Lander. It should be reusable, but that ain't difficult on Luna, so it's a given. I'd build it out of Carbon fibre and plastic. Why? Because those will be in short supply on Luna, and so once the industrial capacity has been developed to the point of constructing basic spacecraft parts (i.e. the hull and a framework to build it on), they can be roasted down to get Hydrogen and Carbon.

Now, where and what should we land? I'd suggest going for the polar regions, since they have a) Peaks of Eternal Light, simplifying the power issue, and b) polar Lunar water. Now, what do we need? Solar panels, certainly. We can likely budget 1kW/kg, if we use the lightest solar panels available (actuall, probably a bit more, but I'll run with it). That means we can get a megawatt of power by importing a tonne, which will be very useful. What else? Some means to shovel regolith into a solar oven would be nice, to drive off the volatiles - I don't have the mass estimates with me, though. We need some way to smelt the regolith; again, I don't have the numbers. Basic metalworking is a much.

What we need to do is draw up a list of everything we need, including the masses.