A Lunar Colony

[arobie]

Scottb50,<br /><br /><font color="yellow">It has to start with a few people paving the way for those to follow. You can't expect to send hundreds of people to somewhere no one has ever been before and expect them to carve out an existance.</font><br /><br />We are not going to send all 100 people to the dome as soon as it is finished. Before people follow, a team will go to the dome to inspect it and make absolutely sure it's suitable for common use. We might also have people up on the Moon for maintanence and repairs of the robots during construction. They could also moniter and control more complex parts of our construction operations.<br /><br /><font color="yellow">Sure it's great to create the enthusiasm to go, but look at the Gold rushes, 1 in 1,000, or less, suceeded.</font><br /><br />Clever, gave me a smile, but I don't think it's apt for this situation. How many people in the gold rush stroke it rich has no bearing on whether or not a Lunar Colony could succeed. The gold miners enthusiasm was created by vague rumors and they went with the intention to personally strike it rich, and they were competing against thousands of other gold miners. This colony is not based on vague rumors, is not out to strike it rich, and is not competing against thousands of other colonies. Two completely different worlds.<br /><br /><font color="yellow">If Tourism is the only source of revenue you can think of then your right, there is not that much money out there to sustain the Moon, let alone Mars.</font><br /><br />Tourism is not the only source of revenue.<br /><br /><font color="orange">If it's a community of people doing things, well that will get the public on board...</font><br /><br /><font color="yellow">What things? Sweeping the reogolith, building igloos, out of lunar basalt bricks?</font><br /><br />How about normal things: living, gardening, cooking, surviving. It's a possibility that they will be building other domes, but not

 

[j05h]

Once you have the machinery up there, it makes sense that part of the population of the first lunar settlement will specialize in just habitat construction. The gear is there with a highly trained crew, ready to build more. <br /><br />One thing I would recommend looking into is Nadir Khalili's SuperAdobe and ceramic houses. He talks about cutting lunar basalt and sintering bricks, but his sandbag-and-barbedwire houses have a lot of potential for space construction. You could land two robots to build domes: a dozer/collecter and a dome spinner. The spinner contains rolls of sandbag, an armature, and a conveyor that goes up and into the dome from the top. The spinner creates the dome from the inside, then climbs out. The dome probably needs to be sintered before habitation, at least on the inside. The sandbag roll's core acts as the keystone, leaving a stable hole in the top. The open top fits an airlock, the user enters and exits like an Indian pit-house. This would make for many smaller domes, perhaps as a precursor to building a larger facility, and is simpler mechanically than robotic cutting, it just requires scraping and filling, some crushing and machines that can operate in that dust. <br /><br />The dust is, by far, the biggest challenge on Luna. Sweeping the area free would reduce it, but you'll never get it all removed.<br /><br />i started that "aqueduct" model, will have something to show soon.<br /><br />Josh<br /><br />http://www.calearth.org/EcoDome.htm <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>

 

[scottb50]

I think the Moon and Mars will emulate the stations in Antartica for a very long time. Which is not a bad thing, once a station is in operation things that can be done there will come into focus. There have been people in Antarctia for more than fifty years and tourism has been growing in the last few years.<br /><br />If you want to do normal things, gardening, cooking it would be a lot easier to stay here. Jobs on the Moon won't just be regular jobs. <br /><br />I would think it would be a lot easier to build a self-sufficient colony in Antarctica then either the Moon or Mars, at least we can breath there and a minor structural failure is definitely not as serious a problem. I'm not saying we shouldn't go to the Moon or Mars, just that we have to put it into perspective. There just isn't that much to do there, just like Antarctica, to draw a lot of people. <div class="Discussion_UserSignature"> </div>

 

[spacester]

NASA will be going there too; they can follow the Antarctica model if they want. But first, we can get started on the dome with robots. Sometime after NASA shows up with people, we show up with people (wouldn't be wise to show them up, don't you know).<br /><br />NASA and ESA and others can do the more conventional and modest things, but we can speed up space development by embarking on a grand project!<br /><br />When it comes to the grandeur of living on the moon, some people get it and some people don't. Those that don't should not be allowed to over-rule those dreamers that know they are in the generation of folks that can get the job done. C'mon, you gotta admit true human flight is pretty cool, right? You strap on wings and flap them and fly! And that's just part of the fun to be had!<br /><br />There is a lot more to do in the unique gravity environment of Luna than could ever be imagined for Antarctica.<br /> <div class="Discussion_UserSignature"> </div>

 

[craig42]

<blockquote><font class="small">In reply to:</font><hr /><p>My domes are not transparent, and the food production would be both inside the dome and in greenhouses, using hydroponics and regolith and compost. It would seem that the only natural lighting of indoor spaces would be the greenhouses, maybe light tubes in the top of the dome, but they're probably not worth the risk. How about: 'closed domes' if no natural lighting, 'green domes' for agricultural domes. <p><hr /></p></p></blockquote><br /><br />I'm fine with those terms but I argue that we should use 'open domes' certainly for the main habitat dome and possibly for the green domes as well.<br />We'll still need electric lights for the lunar night but let's make use of whatever natural sunshine there is.<br /><br />Couldn't this be achieved by building one dome inside another and filling the space between the two with water to filter out harmful radiation but allowing natrual sunlight through? As proposed by Marshall T. Savage. Particularly attractive if sufficient hydrogen deposits can be obtained, the first guy there stands a better chance of getting them than the next guy. <img src="/images/icons/smile.gif" /> 'Night' can be achieved by pulling shades over the dome. <br /><br />Some advantages of an open dome over a closed one are;<br /><br />Avoids loss of energy, due to conversion of power to light.<br />Gives a sense of openness rather than closed.<br />Tourism. What's better, being shut up in a box or a vista across the lunar landscapes (and if in the right location) to where Earth can be seen in all her glory and splendour? (That’s a hell of a backdrop to the holiday photo, beats some guy in a rubber Mickey Mouse suit, hands down.) <img src="/images/icons/smile.gif" /> <br /><br />So what are the advantages of closed domes over open ones?<br />

 

[scottb50]

When it comes to the grandeur of living on the moon, some people get it and some people don't. Those that don't should not be allowed to over-rule those dreamers that know they are in the generation of folks that can get the job done. C'mon, you gotta admit true human flight is pretty cool, right? You strap on wings and flap them and fly! And that's just part of the fun to be had!>>>><br /><br />This is what I meant when I made the comparison to the Gold Rush. You need to think realistically or you end up with a lot of ghost towns.<br /><br />I am all for going to the Moon, Mars and asteroids, but I think you have to keep it in perspective. Perhaps we can do what you talk about, at some point, but the important point is to get there, get a foothold and expand from that, not building an elaborate and expensive structure and hope they will come.<br /><br /> <div class="Discussion_UserSignature"> </div>

 

[spacester]

Scott, I'm not clear on what you're saying. <br /><br />Do you think I have lost perspective by thinking big? That the mere act of thinking big is equivalent to losing perspective?<br /><br />Because I agree with you that <font color="yellow">. . . the important point is to get there, get a foothold and expand from that, . . . </font>and if you stop and look at the plan, you will see that's exactly what it does.<br /><br />After the robots are delivered they establish a foothold and they use local resources to expand from that. It's not the only game in town, you understand that part, right? It's a long term project using leveraged resources, rising the tide and floating the boats of alt.space and space advocates, pulling CATS to market.<br /><br />Certainly it is a vast undertaking, but how exactly does that fact disqualify it as the correct approach? I know there have been lots of disappointments over the years, but we can't just give up on thinking big just because of that.<br /><br />The best that I can make out from your words here is that you either reject the whole concept of ISRU or you do not allow yourself to think big. But my experience with your posts over the years runs to the contrary on both points, so I'm genuinely puzzled.<br /><br />I take great execption to these words: <font color="yellow">. . . building an elaborate and expensive structure and hope they will come</font><br /><br />No part of that is true. It is not elaborate, it is a simple glass lined brick dome, a simple structure made from known materials. It has a huge 'mass multiplier' - see 'Mining the Sky' for that term's definition - and so you end up with a vast structure. <br /><br />But vast does not mean elaborate or expensive. True, it will take more stuff to do the life support, but that's what we can study with this thread - just how many launches of a (e.g.) SDHLV would it take? The space does not need to be furnished right away, and if you have a huge volume, you have a s <div class="Discussion_UserSignature"> </div>

 

[spacester]

craig, I like the open dome concept. I like them a lot. They would be fabulous! The simple answer is that closed domes are much easier to build. <br /><br />Plus, the integrity of the dome as a pressure vessel that will last <b>forever</b> is central to the whole concept. I'm nervous about any penetrations in the basalt and glass for any reason at all, let alone large sections of transparent material.<br /><br />For glass-lined basalt the only "new" technology to be proven is ancient: glass making. We need to develop a way to make a robust glass shell inside the basalt and we need to make glass fiber to tie the dome down to the surface. OK, glass fiber is not so ancient <img src="/images/icons/smile.gif" /><br /><br />I want a building technology that is sure to work. This lets you send robots to start construction right away, avoiding the cost and time involved in preliminary missions. By the time the sweepers are done doing the science and site prep work, we should be making glass on a very small scale (as a piggyback on something else). This informs the next generation glass factories: a small dedicated trial production unit, then a medium scale production unit for the igloo, leading to the full size fourth generation.<br /><br />BTW, I checked in with Nader Khalili again to reconsider the alternative of filling bags with regolith and placing them in a continuous spiral to build your dome. My concern remains (I could be wrong) that sealing that structure and tying it down to the lunar surface will be very difficult. OTOH if you make it nice solid basalt, sealing with glass seems quite doable. Again, it must be designed to last forever. This is a quite different mission as compared to the esteemed Mr. Khalili's very cool and very simple technology.<br /><br />We should get started if we have a way we 'know' will work. By the time the first dome is well underway, glass making and availability of water could very well make the double glass water dome practical. Maybe that coul <div class="Discussion_UserSignature"> </div>

 

[arobie]

spacester,<br /><br />I have not replied to any of the seven posts made by you. I apologize.<br /><br />It is hard to respond to posts that I agree with so much.<br /><br />(To everybody else on this thread, I earlier said, "The ideas that I put out (I can't claim them to be mine)..." This thread is actually born out of ideas shared between spacester, grooble, and I, although we don't know everything we all come to this thread with. Most of spacester's ideas are new to me.)<br /><br />I like your proposed first steps:<br /><br />Establish a power source.<br /><br />Sample, survey, and document the site.<br /><br />Sweep the regolith away.<br /><br />Build the testbed small dome.<br /><br />I assume that our power source will be solar panels on the surface. This poses a problem as we are setting up a power source before clearing the clingly, especially bad for solar panels, lunar regolith. We can either clear the regolith before we set up the panels, or we can set up only enough solar panels to run our dome building efforts before clearing the regolith, and set up more solar panels after clearing the regolith.<br /><br /><font color="yellow">So I'm telling the average Jo "We're going to build a lunar dome that will last forever. We're going to start construction before we send people, because it's more efficient that way. Oh, and does anybody want to drive robots on the moon?"</font><br /><br />I like it. Building a dome to last forever. Cool.<br /><br />I pre-empted you on that last part. <img src="/images/icons/smile.gif" /><br /><br /><b>Safehavens</b><br /><br />I like underground safehavens, and I like the idea of a large underground safehaven so that all the colonists are not split up if something happens, but I also want safehavens to be accessible from all over the dome and having many paths lead to the same safehaven poses a risk. If there is a problem with any one of the paths, that compromises all of the colonists in the safehaven assuming a decompression situation. <br /><b></b>

 

[j05h]

Domes made of rock and regolith (igloo, vault or superadobe) should have enough mass to not need to be tied to the surface. The air pressure under them, even at 14.7psi, won't "push" the dome upward that much. We are talking hundreds or thousands of tons of material for the "forever" domes, air doesn't weigh that much. <br /><br />On sealing any of the domes, I think that directed-solar sintering may prove the simplest and most successful method. I like the idea of sealing it with glass but that process has a lot of unknowns. Sintering regolith should prove easier, it could be done with something like an inkjet printer head with a solar concentrator. The print head moves along the dome in an upward spiral, laying down a consistent layer of sifted regolith, then seals it in place. Precast panels could work, too. I'd consider sealing the dome solid from the outside instead of interior. The robots build the igloo, then partially bury/cover it and seal with regolith and sunlight. <br /><br />I've been thinking about my "aqueduct&barrel vault" setup in regard to the need for a safe haven, and think I have a solution. The structure is built on top of a labyrinth structure that forms a lower, sealed level. If the upper area is somehow breached, several stairs or holes allow very fast access to the rabbit warren under the domes. The tunnel system normally serves as storage, workshops and tunnel access to other domes and the outside. This is consistent with not putting holes in the domes, though I still think (with barrel vaults) that some kind of clerestory or glass bubbles would make for a much more pleasant habitat. <br /><br />One dome idea that would be more temporary is a multi-walled bubble with water and air in the wall layers. Not permanent, but if there is plenty of water available it could prove a quick, shielded space for the construction crew. Not sure if this would work on Mars but the Moon's lighter gravity should allow it. This is Marshall Savage's idea taken <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>

 

[craig42]

<blockquote><font class="small">In reply to:</font><hr /><p>We should get started if we have a way we 'know' will work. By the time the first dome is well underway, glass making and availability of water could very well make the double glass water dome practical. Maybe that could get started as well, who knows? <p><hr /></p></p></blockquote><br />Modules first, Closed Domes second, open domes last. I'll settle for that.<br /><br /><blockquote><font class="small">In reply to:</font><hr /><p>How about one dome at Earthrise and one at Earthset? <p><hr /></p></p></blockquote> Great Idea. I'd love to see how the estate agents would describe that view for prospective buyers <img src="/images/icons/smile.gif" /> Roughly, how far away are the two locations from each other?<br /><br />If in Phase two, we're going to be building closed domes, why not just build underground. Drill a large tube down, hollow out a large underground cavern. Place in structural supports, seal off, pressurise and slap a module on top, to give access. That way we'll already have radiation and micrometeorite protection in place.<br />

 

[spacester]

<font color="yellow">Domes made of rock and regolith (igloo, vault or superadobe) should have enough mass to not need to be tied to the surface. </font><br /><br />So one would think, before doing the calculations. I made that blunder here years ago. What the heck, I haven't done any calcs in a while . . .<br /><br />Let's look at a vertical circular cylinder with a flat roof. It will be pushed up by air pressure and pushed down by the mass of the rock in Luna's wimpy gravity field.<br /><br />Assuming we want a full 14.7 psi (so we can flap around like little birdies), the pressure pushing up the roof is easily found in metric units:<br /><br />14.7 psi = 1.0 atmosphere = 14.7 psi * 6894.75 N/m^2 / psi = 101353 N / m^2<br /><br />The <i>weight</i> of the rock making up the roof needs to be at least that much per square meter.<br /><br />P = rho * g * h<br />P = Pressure<br />rho = density<br />density of basalt = 3.3 gm / cm^3 = 3300 kg / m^3<br />g = 1.62 kg *m / s^2<br />h is what we want to find: How thick does the basalt need to be?<br />h = P / ( rho * g )<br />P = 101353 N / m^2<br />h = 101353 / (3300 * 1.62) <br />Units: (kg * m / s^2)/m^2 / ( kg / m^3 * m / s^2) = m<br />h = 19.0 meters<br /><br />That's 62.2 feet of basalt!<br /><br />And that's just to balance the pressure; we need more than that to make the structure solid.<br /><br />The question is, do you pile on more basalt and regolith or do you tie the structure down?<br /><br />It's an interesting choice: tying it down requires a third building material (glass fiber or aluminum/titanium cables) besides basalt and glass, but you have to move a lot less rock around. Also the inside surface of the basalt dome would be under a tensile load, which brings possible complications for the glass liner.<br /><br />100 feet of basalt is a very very good radiation shield, plus the inside surface of the basalt dome would be under compression, not tension. This would seem to make the sintered glass liner you describe much simple <div class="Discussion_UserSignature"> </div>

 

[j05h]

wow. Those are some impressive numbers. <br /><br />One advantage to superadobe, cast/blown glass and inflating domes over stacked material is that the floor/base can be an integral part of the structure. your glass domes could have essentially two concentric pressure vessels with regolith sandwiched in between. The outer vessel would be more glass or a sintered crust of regolith. The inner pressure vessel could be glass with water and MLI on the outside, assuming a source of lots of water (see my posts in Asteroid thread). <br /><br />A space-adapted superadobe could be layed down in several layers of tubing. Especially for making smallish (say 20-50m diam) domes, they could be laid down in ball or squished-ellipse forms, giving the strong semi-spherical shape. Not sure, but the sandbags might be able to be woven if built over an armature. The dome could be sintered solid then rolled to final location. Many small domes (think homestead/farm) could be a very managable intermediate between modules and Marshall Savage-type domes. A dome that houses a dozen people connected to several industrial and garden domes has built-in safety and a lot more usable space than one large dome. A large base could be built using one central dome-building "spinner" and moving generic domes into place via dozer/trailer. I keep typing "dome" but these are really large ceramic spheroids - "bubbles" probably.<br /><br />Implementing a tie-down structure could use a ring of material that forms a coping facing inward. Coping is made of astrocrete, sunbricks or basalt blocks, the ring is bolted into the bedrock. The dome is built with a lip that hooks under the coping. There are probably dozens of other (right or wrong) solutions. Cables for holding down domes are a recipe for spectacular disaster. <br /><br />I do like the idea of making the pressure vessel one-piece before adding atmosphere. My favorite config is a bubble of reflective plastic sandwich, inflated inside to shape, then the sandwich <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>

 

[tap_sa]

<font color="yellow">"The question is, do you pile on more basalt and regolith or do you tie the structure down?"</font><br /><br />Or do you just make a sphere, sink it half way to the ground, declared the lower portion a 'cellar' and the upper a 'dome' <img src="/images/icons/smile.gif" />

 

[chriscdc]

The easiest way to do this (and most unlikely to work) would be to put a tactical nuke around 200ft underground.

 

[nexium]

Clearly we can build an unsafe transparent sphere with a radius of 2 meters for either Moon or Mars. Improving the safety or making it bigger, means much thicker, which means too little light gets through for agriculture, and a blurred view unless the glass is made to telescope standards. Some kinds of plants will be happy with 0.1 psi oxygen + 0.1 psi carbon dioxide +0.1 psi of water vapor. This improves the saftey for the plants, but the dome will be holed by a pea size meteorite and it is unlikely even genetically altered humans can tolerate 20 millibars for even one minute. Also frequent exposure to the radiation level inside, means reduced probable life span.<br /><br />Instead, I suggest, finding a cave that extends several kilometers below the surface and has a large room at that depth. That way the colonists are safe from radiation, safe from all but huge meteors. The rocks at that depth, all but surely have more volitiles than surface rock, including perhaps easily extracted water. Holigram TV of outside scenes can be made to look like port holes or windows. Neil

 

[contracommando]

<i>“First of all, there is no way NASA well get anything remotely close to a lunar outpost by 2018.</i><br /><br />I agree. For NASA to realistically approach this goal then their budget needs to be doubled or tripled. And that’s not too likely. <br /><br />Unfortunately, the government seems to want to waste money on studies on why prisoners want to escape from prison (real study) or spend millions regulating the size of the holes in Swiss cheese (also real until recently), than increase NASA’s budget.<br /><br />

 

[craig42]

I have not heard of Holigram TV is it the same/simlar to retro-reflective projection technology, like this? It could certainly provide a good image of the surface for underground settlers.

 

[spacester]

nexium, that's good input, thanks. That illustrates that one is tempted to keep the pressure very low to make the structural requirements more managable. But that's a false choice because you need radiation and micrometeroid protection anyway.<br /><br />We need thick walls if we're going to be above ground. Really really thick walls.<br /><br />Digging in makes sense, but it seems to me that the construction effort is increased. Plus we need to dig in really really deep. The regolith is not nearly that deep, right? So we're cutting basalt either way.<br /><br />Either way, we want to show up, survey, do site prep and dig out for the foundation. Then we build up or down or both.<br /><br />But here's the reason a dome makes sense: You have no chance for a view from underground. I'm talking about using your own eyes to gaze at the lunar surface. A view of magnificent desolation through optically clear enough glass to be a very nice view indeed. If you build up and figure out a way to do windows, then you can have a resource unavailable to the burrowers.<br /><br />The greatest resource to be exploited on the moon is<br />Being There<br /><br />So there ought to be access to a great view, a view to be had no where else. From above the top of the dome.<br /><br />You build a basalt dome with rock quarried nearby (creating a big hole in the ground). You dig in at the dome site for safe havens etc, but not as a quarry for the dome material. You line it with glass. You do something better than cables: You bury it very very deep in a very large volume of regolith. (Btw, you sample regolith as you go and get a LOT of data for the scientists.) No penetrations in the dome, access will be by igloo tunnel. So where's the view?<br /><br />There is a small hole in the very top of the dome, right up where the flyers most like to take off from. It has redundant airlocks and rooms to connect to a series of horizontally spiraling glass walled walkways that take you to the views distributed around th <div class="Discussion_UserSignature"> </div>

 

[nexium]

Your link took me to how stuff works.com, but I didn't find retro-reflective. I think hologram TV is still in the laboritory as it requires very wide bandwidth to get good resolution, and the brightness needs to be low to avoid risk of eye damage from the lasers. Disney World in Florida uses several moving holigrams of low resolution and low brightness. Neil

 

[nexium]

Hi spacester: I think that will work as you said. Occasional brief visits to even a thin walled transparent dome will shorten life expectancy only slightly. 3psi with 98% oxygen, instead of 14.7psi with 21% oxygen, will improve survival probability, if the dome explodes in your face due to a meteorite hit. A dome failure detector could drop your agonized body though the floor into an airlock, from which you would be rushed to the emergency medical facility. It might happen only twice per century, so the risk is less than driving on the free way by the hour. Neil

 

[nexium]

I agree cutting though basalt will drain a lot of resources. Earth has lots of natural caves, most full of water. Mars (and perhaps the moon) likely has lots of dry caves in the two kilometers closest to the surface. Lower gravity, may allow the caves to be larger and/or deeper than Earth typical. I should think, material other than basalt should occur 2 kilometers below the surface at least rarely on both Mars and the Moon. We have pefected a ground penetrating radar that finds caves (and other anomolies) easily to more than 2 kilometers depth. Neil

 

[craig42]

That is where the link is inteded for the 3rd bullet point mentions using for a windowless room. Retro-reflective is the material used on the cloak in this systemn and has everday uses as well such as bicycle reflectors. Which this earlier page of the article mentions.

 

[spacester]

My limited understanding of lunar geology leads me to believe that caves will be very rare there. They represent an unknown resource. A cave-dwelling strategy requires the use of significant resources to verify the concept. Plus, if that is our building technology, that's where we have to live. Not the same thing as building what you want where you want.<br /><br />I'm looking for a building technology that allows construction to begin almost immediately while maximizing ISRU<br /><br />That being said, a ground penetrating radar is a high priority mission for the science community if they want to understand Luna. Why exactly is the gravity so lumpy? Could it be due to massive caves somehow? I doubt it, personally, but it deserves to be looked into.<br /><br />Are there lava tubes on the moon? Where exactly would we look for them? <div class="Discussion_UserSignature"> </div>

 

[spd405]

Caves would be rare on the moon unles there was a period when it had flowing water for long enough to do the erosion.<br /><br />There is an article in the Journal of the British Interplanetray Society about using radar remote sensing to detect lava tubes to use as bases - caluculations based on earth tubes suggets lengths of up to 380 metres and an overburden of about 50 metres. The article was written by a Thomas L Billings (Lunar Base Research Team, Oregon L-5 Society, PO Box 86, Oregan City, Oregan 97045-0007) and is in the June 1991 edition of JBIS.<br /><br />There was also one about the engineering geology and soil mechanics of the moon with regard to use of in-situ materials for building - this was written by Stewart W Johnson (Johnson and Associates, 820 Rio Ariba, SE Alberquerque, NM 87123), Koon Meng Chua (Dept of Civile Engineering, University of New Mexico, Alberquerque, NM 87131) and W David Carrier III (Lunar Geotechnical Institute, PO Box 505, Lakeland FL 33807-5056) and was in the January 1995 issue of JBIS.<br /><br />Unfortunatley, none of the JBIS articles are avaialable on-line (as far as I know) which is a shame as there are some very good ones.