The Practicality of a Lunar Colony

[Comic]

Hello,

I apologize ahead of time if this topic has been inappropriately placed. I am clearly new to the board and do not wish to step on any traditions or regulations, so please bear with me. I will also clarify that I have only a passing familiarity with this forum and its atmosphere -- I have never quite lurked, but I have browsed a few topics from time to time over the years -- and it is my meager understanding that brings me here in the first place.

Right now I am in the process of sketching out a few ideas on a potential fiction piece centered around a distant future where a functional Lunar colony has been established. I intend for the novel to be somewhat political, partly techno-legal-thriller. The long and short of it is that I am sketching out the preliminaries and I am intensely researching the scientific and technological aspects of a feasible lunar colony -- possible with, say, early 22nd Century technology.

I want to state up front that I am not substituting actual research for the informed opinions of the intelligent members of this community. I am merely requesting feedback, opinions, suggestions, and referrals that can guide me in the proper direction in how to go about establishing the scene for this colony to appear both authentic, not just in terms of function but in its establishment. Clearly I can seize as many creative liberties as I wish, and fully intend to do so, yet I still would appreciate the air of plausibility -- authenticity -- that would leave the layperson to think, "That could probably work!"

First, a little bit of background for the "geopolitical" scene, as it were. Essentially, my vision for this colony is that it is politically independent of the Earth; no nation-state existing at that time would have claim to the Moon's surface. It operates independent of any bureaucracy, and is probably organized close to the tradition of Robert LeFevre's "autarchy." The extent of Earth's interest in the Moon is corporate, so I envision a major industrial complex with aerospace, engineering, and privately funded science labs dominating the landscape. Most of the housing would, by extension, constitute "employee housing." One of my ideas, as well, is an orbital shipyard where construction is underway of a prototype transport for the eventual colonization of Mars where small, manned expeditionary outposts are already established. The logic for the shipyard being in lunar orbit is that Earth orbit is far too cluttered with space junk to make such large scale construction feasible.

My questions mostly concern technological and scientific aspects of this colony, such as. . .

• How do they bus large numbers of people to the Moon in the first place? One thought I had, though I am not sure how cost-effective it would be, calls for three distinct craft -- all re-usable. One would take the migrants from Earth to rendezvous with an orbital platform where you would change "space planes" for a much more luxurious cruise-type ship that would accomodate you to lunar orbit, where another platform would be waiting with shuttles to the surface. What I'm truly hung up about how could the "Lunar Landers" be designed to be re-usable, as opposed to the Apollo model that used a two-stage, disposable lander?
  
  Additionally, the transport of cargo, not simply that of the passengers mind you, I assume could be handled in a similar fashion to modern airlines of today where weight and balance would be determined by the passenger volume of the route and carrying capacity of the equipment. However, considering we are discussing interstellar travel, any hidden snags I may be missing on this point would be greatly appreciated.
• Location, Location, Location. What would be the most likely location for an actual colony on the Moon? One that would allow for the vast temperature differences that can be experienced on the lunar surface. Where, if anywhere, on the surace is there the least variation in surface temperature that would not wear thin any potential futuristic thermal shielding in short order?
• What sort of permanent structures could be established on the lunar surface? Moreover, what would the habitats consist of? My thinking lies along the lines of arcologies with aeroponic agriculture to provide at least partial self-sufficiency.
• Does the Moon possess any minable resources that would contribute to the lunar economy?
• I'm thinking of adding a space tourism component, but I am afraid that even in the distant future I envision it might just be too expensive to be anything but folly for the rich. Still something to consider, however.

Okay, that's where I'm at right now. I remind you that I am not asking for anyone to do my research for me. A lot of this I have probably already looked into myself, what I am most curious about is what I might have missed. If you can point me to a resource -- be it a website, a book, or anything I can find in a public library -- it would be just as helpful. Your own educated input is, of course, welcome.

I caution that I will prefer as many print resources as I can get my hands on, as I am homeless and without regular Internet access, much less the time to spend reading pages and pages of words-on-a-screen. And consider me unable to view PDF or any sort of document format as a whole if I can't get Google to convert it seamlessly to HTML.

Thank you all in advance for your time and energy.

[Whiskey144]

How do they bus large numbers of people to the Moon in the first place? One thought I had, though I am not sure how cost-effective it would be, calls for three distinct craft -- all re-usable. One would take the migrants from Earth to rendezvous with an orbital platform where you would change "space planes" for a much more luxurious cruise-type ship that would accomodate you to lunar orbit, where another platform would be waiting with shuttles to the surface. What I'm truly hung up about how could the "Lunar Landers" be designed to be re-usable, as opposed to the Apollo model that used a two-stage, disposable lander?

That's actually a method that's been "used" before. Whether it was tabled as an actual proposal for space industry, or more likely it was used in a fiction story, I can't remember at present. But yes, that would work very well, and indeed, is a highly optimized system.

A site I am regular reader of, Atomic Rockets (Google is your friend), suggests that a competent rocket designer would actually not design a ship that goes from surface-to-surface between 2 different planets, and would instead optimize an orbital transport and a "shuttle" craft for the two tasks.

Where I think you may trip up is the reusable Earth-liftoff ship. Chemical rocket technology is very mature, and all present indications are that chemical-rocket, reusable (I presume you wish for Single Stage To Orbit?) lifters are......difficult. And hideously expensive. The Shuttle system is only partially reusable (the external tank burns up on reentry), and is quite expensive.

With the Lunar Landers, an Aluminum/Oxygen rocket works very well. Crap efficiency compared to other chemical fuels, but it works great for Lunar area with the 1/6th of Earth gravity and the bonus of both materials being plentiful in the Lunar regolith. While the specific impulse is only 285 seconds (~2.8 km/s exhaust velocity), an Aluminum/Oxygen rocket can easily perform Lunar liftoff/landing, and even a flyby trajectory to/from an L5 colony. Bonus points for no fuel importation from Earth.

Additionally, the transport of cargo, not simply that of the passengers mind you, I assume could be handled in a similar fashion to modern airlines of today where weight and balance would be determined by the passenger volume of the route and carrying capacity of the equipment. However, considering we are discussing interstellar travel, any hidden snags I may be missing on this point would be greatly appreciated.

I think you mean interplanetary, or perhaps cislunar. Because interstellar is like a Sol/Alpha-Centauri run, and pretty much impossible when your destination is only a few light seconds away.

Otherwise, I've no idea.

Does the Moon possess any minable resources that would contribute to the lunar economy?

Three, at least. There's a little bit of Helium-3 if you have fusion reactors (that run on Helium-3 reactions), but the more important and useful are Aluminum and Oxygen, which, as noted above, can be used to build chemfuel rockets that are capable of Lunar liftoff and landing.

I'm thinking of adding a space tourism component, but I am afraid that even in the distant future I envision it might just be too expensive to be anything but folly for the rich. Still something to consider, however.

It depends heavily on the volume and type of traffic. If there's a lot of people being bussed up to the Moon, then the tickets might be relatively affordable (only a few $1000s), but the opportunity might be relatively high, as you'd have to plan very heavily in advance and the numerous medical procedures that might or might not be required (depending on your setting).

So you might have affordable space tourism, but not a whole lot as people mostly view it as "more trouble than its worth".

If you can point me to a resource -- be it a website, a book, or anything I can find in a public library -- it would be just as helpful. Your own educated input is, of course, welcome.

Here you go: Atomic Rockets. It also has numerous useful links sprinkled throughout.

[doom3607]

Do you have useable-length carbon nanotubes in your setting? If you do, freight shipping should probably just involve running it up a space elevator and then firing it out of a cannon to a receiver attached to the elevator on the Moon- or on Earth, if it's coming from the Moon. Failing that, just shuttle it up and use a cannon. A nuclear reactor up there would mean you don't have to keep burning mountains of spaceship fuel to get stuff from Earth to the Moon.

[madd0ct0r]

a space elevator was my thought too.

if earth is chronically energy hungry, then exporting that might be feasible - either as microwaves to a receptor (corporation with a death ray!) as helium3 for reactors or by doing energy hungry tasks - production of aluminum comes to mind.

Avoiding thermal swings? underground is your answer. If you're strip mining the moon anyway, you should have plenty of spoil to heap up on the domes for shielding. 19th century wales they managed to loose mountains and valleys in spoil heaps, and we're capable of much bigger scale stuff now.

I'm thinking about the dust and debris created though - there's no wind to blow it but you might end up with a constant dust 'fog' around the mine area. Miners then becoming 'Dusties' or 'Dust necks'. Presumably old timers would be 'Loonies'

I'm assuming it would be expensive for a corporation to send someone to the moon. Not for the flight costs, but the relocation demands. Especially with the effects of low level gravity you'd be looking at much more then the pay multiples used when they send senior management to third world countries. Further assuming you've got half decent lunar industry, this would lead to it being too expensive to send all but the best who are needed to manage robotic fleets and factories.

This cost to the company might be basic salary; gaining privileges when you get back; providing a brilliant living standard on the moon or being able to escape earth (depending on how horrible you let it become).
Then again, how many people are needed to grease the social wheels? you mentioned you wanted an arcology - but won't that require certain minimum populations? If it's pretty barren, you might have people volunteering for lunar work because they don't like other people much - the stereotypical grumpy prospector. On the other hand it might be entire teams sent together - much like army units or certain engineering companies where it can be a bunch of men who work as a team or a full team and their families.
The two give you very different social environments though.


Have you read Kim Stanley Robinsons Mars Trilogy?

[MrDakka]

Whiskey 144 already beat me to it, but Atomic Rockets is probably the best site available for your research. It summarizes all the information you could want on space travel and colonization, with links and references to back it up.

If you want a little more hard science and actual numbers, I'd recommend getting a couple books about rocket propulsion, orbital mechanics and space system design. I don't know what specific books to get regarding the latter two subjects, but I had to buy Rocket Propulsion Elements by Sutton last year for class and it is pretty much the de facto text about chemical rockets.

[sirocco]

You could also have a look at the Planetes anime.

The main setting during the first part is a station orbiting around Earth but the second happens on the Moon. That should give you some additional ideas.

[Skgoa]

A couple of thoughts:

- Reusable lunar landers are no problem. You have an industrial base on the moon, so you can just refuel them. The Apollo lander was built the way it was because they had to bring everything with them and had to reduce weight as much as possible.

- Yes, Earth Orbit Rendezvous and Lunar Orbit Rendezvous are the way to go. For getting people into LEO, take a look at the X-34 or the X-37. A scaled up version could either be launched by rocket (if you want to be fancy, choose a reusable SSTO) or you could have it depart airports like any airplane, go up to hypersonic speed and above most of the atmosphere using an air breathing scramjet and switch to a rocket engine for the last part. Then you either dock with a station in LEO or rendezvous with a robotic space tug and let that one pull the shuttle to a higher orbit. Fun fact: if your civilization has managed to capture a comet, they can get water (and thus hydrogen and oxigen, i.e. fuel) almost for free. For the transfer between Earth orbit and lunar orbit, something like NASA's Nautilus** concept would be used. Make sure to mention the inflatable modules and the centrifugal ring in detail. The transfer would be made using a Hohmann orbit and would take several days. Passangers and Cargo might have to wait at either of the orbiting stations for a couple of days to catch an optimal launch window.

- Bulk cargo (i.e. anything bigger than normal luggage) will not fit through bulkheads made for humans and thus will have to be transfered from one ship to the other outside the orbital stations, most probably by robotic arms. If your cargo needs a pressurized environment, it will have to be in a pressurized container. I would bet large sums of money that those containers will be standardized and you can just book space and weight in them.

- I would advise against using huge cannons/railguns in orbit. Actio est reactio and all that. Railguns have the additional problem of strong electromagnetic fields.

- The question of location is still a being researched. For the first outpost one of the poles looks a good bet, since there are craters that never see sunlight (and might thus have a high amoun of water ice) and summits that are never without sunlight. (great for solar energy) But after that outposts would spread to anywhere we think there is something valuable in the ground. The Moon is HUGE and different industries will favor different locations.

- On the moon, people would most probably live under the surface, as has been mentioned already. Power would be generated from fusion plants. (hey, its the future and the Moon has He3!) But there will also be structures on the surface, since burying stuff is a lot of work. Things that don't need to be sheltered against radiation and meteorites (i.e. stuff that isn't delicate and that one can survive the loss of) would be stored in inflatable modules that are covered by a relatively thin layer of material that is produced from the digging/strip mining that is going on anyways. What structures they will or will not build depends on many things, first and foremost whether this is an industrial outpost or a true colony with children. You would need quarters, food production/processing/distribution, hospitals a multitude of infrastructure etc. etc. One thing they will have for sure at every bigger outpost will be a space port with the neccessary equipment to haul fully loaded landers into pressurizable loading/unloading/maintenance docks. A shirtsleeve environment is just so much better for handling things, especially repairing high tech equipment.

- Space tourism is already getting of the ground, we will see space hotels before we have a permanent base on the moon. And once the hard part (i.e. getting into orbit) has been delt with in an economically viable fashion, there is no reason people wouldn't want to go to the moon.

- For an introduction to rocket and space science I would recommend http://www.braeunig.us/space/basics.htm Atomic Rockets is an ok website if you want to get inspiration from what other authors have come up with. But as soon as "realism" enters your equation... its better not to trust that site.


* http://en.wikipedia.org/wiki/Orbital_Sciences_X-34 and http://en.wikipedia.org/wiki/Boeing_X-37
** http://en.wikipedia.org/wiki/Nautilus-X

[someone_else]

The logic for the shipyard being in lunar orbit is that Earth orbit is far too cluttered with space junk to make such large scale construction feasible.

Mh, if you have space tugs then space junk isn't an issue anymore. Hell, even the dreaded Van Allen Radiation Belts can be nuked with not-so-fancy tech.

The main reason about doing it on the Moon imho is that the moon has ample supplies of aluminum, the main component of any rocket. On the Moon you can manufacture from scratch rockets weighting fucktons without the hassle of lifing all that mass (and bulk) up from Earth. From Earth you will still ship the more complex parts, like engines, electronics and similar.

Also the moon is a fuel supply for them too.

How do they bus large numbers of people to the Moon in the first place?

Surface-Orbit: Either something mass-produced, dumb, cheap, reusable and scalable for different payloads like OTRAG, or something using beamed power to heat the fuel on a relatively dumb SSTO aerospace plane.
If you really wanna go fancy, try skylon, a SSTO aerospace plane that should work in theory.

Orbit/orbit: any chemical rocket will do if you have fuel facilities on the Moon and in EML1 (earth-moon lagrange point 1), but you also have the chance of using momentum exchange tethers. A video, a pdf paper.

Moon Lander/lifter: No need to multistage here, Apollo Lander was using crappy (but safer) non-cryogenic fuels, but you don't need to, since the Moon can provide LOX and LH2, and those give your rockets more than enough endurance to get in lunar orbit and get down again with the same payload on the same fuel tank (then you must refuel them).
Still, you can go fancy here too and make Moon Elevators that since the moon has a crappy gravity and no atmosphere can be done with modern materials (it is an elevator moon-surface/moon-orbit, does not bring you to Earth).
Or place a moon railgun to launch stuff into moon orbit (but then you must figure a way to come down again, and it's likely only for cargo).

Where, if anywhere, on the surace is there the least variation in surface temperature that would not wear thin any potential futuristic thermal shielding in short order?

That's not an issue. The issue is Moon dust. The fucker is very fine and very abrasive. Which means anything in contact with it will have to be designed to prevent it from going into stuff. And space suits must be stronger than those used in orbit. Not that it's impossible to do, but that's a problem you can talk about.

Does the Moon possess any minable resources that would contribute to the lunar economy?

He3 mining is idiotically unpractical (100'000'000 tons of lunar soil processed to get 1 ton of He3), and assumes you have advanced fusion generators online (the current fusion generators fuse deuterium and tritium).

But still, there are platinum group metals, gold and nickel. Not from the moon soil proper, but from fallen asteroids. And as you can see, the moon has lots of craters.

Also thorium, a not overtly radioactive element that can be used in clean and safe fission power generation, in theory. There is plenty of the stuff on Earth too, but what is there is useful for Moon-based power plants.

There is also water ice near the poles. And that is useful since you can crack it to make oxygen for breathing, drink it, or make rocket fuel. And rocket fuel coming from the moon should be far cheaper than lifting it up from Earth.

Then of course, there are fucktons of aluminum/iron/silicon to build anything else.

I'm thinking of adding a space tourism component, but I am afraid that even in the distant future I envision it might just be too expensive to be anything but folly for the rich. Still something to consider, however.

In fact that's the more likely thing to conquer space in Real World. Space Hotels.

Platinum group metals are used in electronics and anything working with electricity in general (from solar panels to superconductors). So we can't go without, but currently it's far cheaper to subsidize crime lords in Africa to have access to the mines of such minerals (that were basically fallen asteroids) than going to the moon. Just state that mines of such stuff have been exhausted or that political situation there prevents mining... or whatever.

If you can point me to a resource

Here you go, a site about lunar and asteroid colonization/exploitation. Lots of answers to your questions.

Also, while others suggested Atomic Rockets, I'll link you to a page that you should read first to get an idea of why your companies are in space to do businnes. Here it is.

I caution that I will prefer as many print resources as I can get my hands on

I'm sorry but most of what I know is on the net.

And consider me unable to view PDF

This site allows you to see PDF and does not have annoyances or ads.

[Skgoa]

The main reason about doing it on the Moon imho is that the moon has ample supplies of aluminum, the main component of any rocket. On the Moon you can manufacture from scratch rockets weighting fucktons without the hassle of lifing all that mass (and bulk) up from Earth. From Earth you will still ship the more complex parts, like engines, electronics and similar.

With it's low (but still sufficient) gravity the Moon is the ideal environment for industry/construction, too. The cost difference between continuously supplying a station in Earth orbit and a (mostly) self-sustaining Moon colony alone means the higher upfront investment will pay off. And industry needs space. Digging a big hall into the lunar soil should be much cheaper (we are strip mining the place, remember?) than constructing a station of equivalent size, if the latter is even feasible.

The issue is Moon dust. The fucker is very fine and very abrasive. Which means anything in contact with it will have to be designed to prevent it from going into stuff. And space suits must be stronger than those used in orbit. Not that it's impossible to do, but that's a problem you can talk about.

Yeah, everyone going for a moonwalk will have a brush with him. Also, everything that moves on the ground (or is near something that does so) and runs on solar power will either have an automatic brush for the solar cells - and optical sensors etc. while we are at it - or will have to be cleaned by hand. Now that I think about it, that might be an excelent excuse to have people outside at regular intervals.

[Simon_Jester]

Careful with those brushes, of course. You don't want to grind fine, abrasive rock dust against the surface of just any object.

[Whiskey144]

Moon Lander/lifter: No need to multistage here, Apollo Lander was using crappy (but safer) non-cryogenic fuels, but you don't need to, since the Moon can provide LOX and LH2, and those give your rockets more than enough endurance to get in lunar orbit and get down again with the same payload on the same fuel tank (then you must refuel them).

I'll point out that an Aluminum/Oxygen rocket, while having about half the specific impulse, would probably be a much cheaper option- both elements are very abundant in the Lunar regolith.

[Zixinus]

Just a thought on getting your spaceplanes to Earth orbit: magnetic launching rails may help speed up the craft without it needed to use it's own fuel.
I cannot however remember the proper name for such a concept. Certain ideas involve using a Gauss-gun like system.

I assume could be handled in a similar fashion to modern airlines of today where weight and balance would be determined by the passenger volume of the route and carrying capacity of the equipment.

The key concept is mass. A rocket is very, very weight-sensitive. The more a passenger weights (on Earth) the more fuel you need to expand.

Others have already pointed out Atomic Rocket. I recommend it myself.

There's a little bit of Helium-3 if you have fusion reactors (that run on Helium-3 reactions)

Just to elaborate on this bit, if I may.

Helium-3 is not the only fusion source, as the sun already fuses a lot of things. Most fusions with elements lighter than iron typically produce energy.

The trick is making a fusion reaction work economically (ie, you get much, much more energy out than what you have to put in). To do this, you have to pick a fusion reaction that's "easiest" to do (requires the least energy).

The easiest is Deuterium-Tritium (two heavier isotopes of hydrogen) reaction. That is what they experimenting with now. This reaction is the easiest to do and produces neutrons. Neutrons can be only put to use as heat, so you'll need the whole steam-turbine-generator cycle. With good design and the like, you'll get perhaps 40% efficiency or so. The waste you'll have to dump as heat, which can be a problem in space .

However, there is a reaction that is only slightly harder (depending on a variety of factors): Deuterium and Helium-3. The difference? You get charged hydrogen, energetic ions instead of neutrons.
Why does this matter? Because you can harness the ions, creating current. That means you can harness the reactor's energy with up to 90% or perhaps more efficiency (of course, this depends on the design and such).

There is a proton-Boron reaction that too produces ions fairly reliably, which requires far less exotic (regular boron and hydrogen essentally) fuel but is much harder.

Perhaps not worthwhile on Earth, but for spaceflight, a high-efficiency and light fusion reactor may be desirable. Just remember that mining it is going to be a bitch and a quite complicated because He3 gets there in the form of solar wind.

I caution that I will prefer as many print resources as I can get my hands on, as I am homeless and without regular Internet access,

Huh? You're... homeless? Could you please explain?

[someone_else]

Digging a big hall into the lunar soil should be much cheaper (we are strip mining the place, remember?) than constructing a station of equivalent size, if the latter is even feasible.

How could I have forgotten the NUCLEAR SUBTERRENE? The concept was designed for moon base construction after all.

I'll point out that an Aluminum/Oxygen rocket, while having about half the specific impulse, would probably be a much cheaper option- both elements are very abundant in the Lunar regolith.

Yes, but that means you will empty your tank by just reaching lunar orbit. Since you'll want to stay near water ice anyway, using LOX and LH2 seems a better bet.

Just a thought on getting your spaceplanes to Earth orbit: magnetic launching rails may help speed up the craft without it needed to use it's own fuel.

The issue with that is that on average the rail will be very low in the atmosphere. Air drag will be a killer. Just look at railguns. They reach ludicrously low speeds (for orbit insertion anyway) and yet they have plasma everywhere.

[Skgoa]

Yeah, the issue with most "space alternatives" is that they break down once in contact with reality. Its a pretty well known fact in rocket science that the total energy you have to impart on your payload would cost in the single Euro range if taken directly from the electrical grid. But inefficiency in (and inability of) transfering that power forces us to spend hundreds or even thousands of millions on space launches.