Monday, September 5, 2016

All the Reasons Why

Moonwards is a bit of a different approach to promoting space. It seems time to properly summarize that. I'm on The Space Show next Sunday, Sept. 11th, and i need to organize my thoughts. It hasn't seemed useful (up to now) to contrast it with various other projects out there, so this gap keeps reappearing where people wonder why it isn't done like x or y.

99% of the imagery of space that most people see is in fiction, there is a huge quantity of material. For most people, what we are really doing in space is pretty boring by comparison. Unless they have a background in the sciences that allows them to appreciate it, it just isn't going to hold their attention. However, the growing proportion of popular fiction that takes place in space is a signal of something important. Human cultures are increasingly transferring their broadest vision of our hopes and dreams to a space setting. If you want to reach people, and get them thinking about what the road to our greatest dreams needs to be, tapping that has huge potential.

So Moonwards is building a bridge between the vast energy placed in fictional visions and something that could actually be done. It seeks a keen balance between realism and fantasy that powerfully makes key points about who we are and what we should pursue. A city on the Moon can capture the imagination. Yes, you could fly by flapping wings, needing only your own strength. Yes, you could leap from the water like a dolphin. You could carry 10 people on your shoulders, jump to the roof of a house. You could run for miles and miles without exhaustion - you could just run wherever you go without it being a big deal. You could run everyplace with a friend on your shoulders, and switch occasionally between who is carrying who. The scale of what we could build there once we built up infrastructure would also be that much grander. Ladders into space, skyscrapers miles high, pits miles deep.


When you paint a picture like that, and say that isn't a fantasy, that is what it would really be like, that makes an impression. I could go on at great length on how that impression can have a ripple effect on how people see the value of things in general, and their willingness to work together to achieve the great things that can only be achieved together. But there are other things to cover...

There are several plans out there about businesses or colonies at a lunar pole, and yet Cernan's Promise is placed at the equator. The main defense for this is the building approach. Basalt is needed in order to build big quickly. Only with basalt can you make everything needed - the cables that contain the pressure of atmosphere, and the many different construction materials for arches, columns, floors, walls, and furnishings. Only by building large can you have long-term residents who don't go crazy but are actually happy. Selling residence is the core business of the colony in the initial phase, augmented by broadcasting that can also only be done successfully in a large, beautiful building. If you try to build large and beautiful with any other technique, it takes so much machinery to do that you might as well have used that mass to bring up the machinery to melt and process basalt. The machinery needed to create waterless concrete and build with it would weigh much more (and need rebar), the machinery to excavate and emplace regolith over inflatables would weigh about the same as the machinery needed to excavate and build with fused basalt and basalt cable. If you want something larger than an inflatable that can be rolled up and packed within a fairing, you also need equipment to stitch and weld seams that are reliably strong, and to maneuver large pieces of fabric without damaging them. Unless you reinforce the inflatable with elements strong enough to support the regolith overlay in the event of loss of atmosphere, you risk complete disaster if something rips the fabric - a fire, an explosion, a chemical spill, one person who completely loses it for 30 seconds. But if you put in that reinforcing structure, you might as well just have built out of basalt, in which case you could have built all your furnishings and internal structures in the bargain with the same machinery, and also more entire habitats.

Because it is at the equator, Cernan's Promise can't take advantage of the water and other chemicals frozen in the ground of the poles. We don't know how difficult it will be to mine the poles for water. It might be easy, but it might be very hard. I really doubt there will be a viable market for water as rocket fuel, so the money that would be spent setting up mining is better spent sending a payload of water to the equator, and methane to power a nuclear thermal shuttle. Because Moonwards looks purely at the potential of our technology, planning for nuclear ships is a logical step. That means fuel supplies can be stretched much further, especially once you add a cargo ship running on ion engines shuttling between lunar orbit and LEO. The nuclear shuttle just needs to go to orbit to unload the cargo ship. By the time the colony needs more water than can be accommodated in the payload budget it has with Earth, it will be capable of building most of the mass of the machinery and habs needed for water mining itself. Those can then be taken to the north pole for much less fuel than if everything had to be brought from Earth, and fewer Earth launches would be needed.

More about the transport solution is in the previous post. That post is also going to be updated in a few days with input from Sigvart Brendberg, who made some very salient points recently that really improve it. Like pointing out the nuclear shuttles should run on methane, and the cargo ship should be launched as the second mission, instead of a nuclear shuttle going all the way to LEO. I'd like to highlight again the importance of tethers. Tethers in lunar orbit makes movement of bulk cargo around the moon feasible, and also movement between the surface and lunar orbit. That is critical if the Moon is to become mostly free of shipments from Earth. If you can't get all the volatiles you need from the poles, you can get them by bringing carbonaceous asteroids to orbit. With just one polar tether you can get transport coverage of most of the Moon, so once you find the craters where meteors impacted with speeds low enough that remnants of them remain there, you can find metals, hydrocarbons, and nitrogen chemicals there, as well.

By accepting nuclear power into our lives, Moonwards also solves the energy problem of the long cold nights, which polar colonies handle by staying on peaks where there is sun 90% of the time. Nuclear generators will power the colony in the early days. Since everything is being made of solid basalt, and there are also a lot of boulders around at the site of Cernan's Promise, thermal mass will make temperature regulation way easier. Machinery outside will be protected from the cold on solid basalt platforms warmed by the sun during the day, tucked under reflective tarps that trap the heat. Later a hangar with a thick basalt floor and several layers of reflective insulation suspended tent-style over the whole space will keep temperatures quite even.

I think those are the things i wanted to cover... One last thing is that the influence a true colony would have on Earth, a colony with at least a thousand people, that is developing its own culture, is hard to overstate. Transmissions between the Moon and Earth would be literally a million times what that transmission power could send between Earth and Mars when they are farthest apart. Running a hundred 4K channels all the time would be no problem, with all the video calls and file transfers you could possibly want on top of that. Places that are entirely new encourage new ways of thought, and that tends to be very powerful. An example i think is relevant: American Revolution, 1776... French Revolution, 1789.


10 comments:

  1. Not on the topic of this particular blog post, sorry. But I'm wondering about the difference in what materials would be available on the Moon compared to the Earth. And its implication for architecture and even culture. There will be no wood, plastics or textiles on the Moon, right? Instead glass, ceramics, light metals. Things like furniture and utensils would be made out of magnesium, which would be a pretty exotic thing on Earth.

    Can soft things be manufactured from Moon materials? What kind of clothes would one make there? It would be a bit kinky to walk around in aluminium foil and titanium shoes.

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    1. Given the low gravity, maybe one could sit comfortably in a sofa made out of glass on the Moon, and sleep on an aluminium bed.

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  2. I have thought about this too. Basalt fibers could be stuffed in basalt cloth covers to make cushions and such. That is an option early on. You could make inflatables that only need a small amount of sealant from Earth, and use those as mattresses. Or you could make hammocks of basalt cloth, and take the time to shape them and give them a frame so they are comfortable to sleep in (which i don't find to be the case with hammocks on Earth for any length of time).

    But the point you make is also a good one - how much padding do you need if you are in 1/6th gravity? Consider that in such a place the weight you bear on the soles of your feet when you are standing is less than the weight your butt bears on Earth when you are sitting. It might not only be healthier to stand all the time on the Moon, but genuinely more comfortable. But when you want to relax enough to sleep well, the familiarity of a mattress would probably help with that. So it is good that there are options for that in the early days.

    I am sure there will always be important roles for plastic, as it is such a versatile set of substances, but only for where nothing else will work. Once carbonaceous asteroids can be put into orbit, and there is high-capacity transport by means of tethers that make mining of those, and of any deposits on the Moon, possible, there will be some plastics. I bet that with the characteristics of lunar glasses, either based on basalt or other mixtures of common minerals there, many everyday objects would be glass. Lunar minerals are free of the effects of hydration, and they are highly reduced - they have extra electrons. The best guess is that this means lunar glass will be stronger than Earth glass. Maybe not a great material for forks... But glass chairs sound perfectly fine. After all, glass can be formed into nice natural curves that fit your body. If you want to sit at all, of course. For finely detailed stuff, i bet on iron. Magnesium tends to react with water. So does iron, but at least it doesn't do so violently.

    There is so much to think about... I find it rather fun. :)

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    1. There are very few visionaries out there with the imagination to visualise things in such detail I love the website it inspires discussion which is what is required to make dreams reality. With such vision there is always the realisation that this vision has to be shared by many others with a whole lot of other skills to make this happen.

      I often wondered why we never built a habitat on the moon and instead are looking at a far more ambitious project like Mars when the theoretical issues could have already been explored on our nearest neighbour at little cost and within our current technological scope.

      I guess those with vision are always chasing the new challenge. Because they haven’t been to Mars, but have been many times to the moon, they don’t see that as interesting any more. To be first for visionaries is always the first priority before they move on.
      Those of us that have not shared in that experience are left to try ant imagine what it would be like.

      I wonder about the solar aspect when you have 336 hours of darkness at night this will make thermal mass heat retention a problem. Perhaps some form of bio-heat production from waste producing heat as well as methane for additional heat input within a circulated water system.

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    2. Hi Sam

      Heat only moves by radiation in a vacuum. For the parts of the habitat that are underground (which is almost everything), heat is also conducted by contact, but powder regolith is excellent insulation.

      On the website, if you look at the model of the finished dugout, there is a spot where it mentions that tubing would be laid in channels cut into the huge boulders located at its north end - each of which is the size of a large house - and water would be circulated through them for temperature regulation. The stone arches covering the dugout may also have tubing along the top of each one so water can be circulated through them to shed heat at night

      The idea there is that with time, the issue is going to be how to shed excess heat that has collected in the habitat during the day. Those boulders can suck up a lot of heat but eventually they will not cool below room temperature even overnight. I have thought about making a simple, movable shade of reflective foil for them so the sun doesn't reach them in the day. The value of the thermal mass in the dugout is that it takes long enough for temperatures to change that you can use much simpler and smaller heat regulation systems to stay within a comfortable range. I believe the very simple system i mention here would be enough.

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    3. I am concerned that as the day and night are 13days long that this heat will be very hot and as you say shedding heat perhaps using steam to generate power? and perhaps ducting heat to shaded areas that are cooler maybe sub surface. Im not sure what the temperature gradient would be say 100m below the surface?
      The 13 days of -190c for 2 weeks would be more problematic and would require external heat input to be generated without solar it would require an external source of power to maintain thermal balance this of course could be over come in the longer term but short term initial missions Im not sure?

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  3. We can have artificial light of course for the darkness or sun pipes for underground light during the 14 day daylight phase.

    This will always impact on our mental health as well as the long term weakening of us physically at 1 sixth gravity and the health issues that this may manifest.

    Nuclear power would as you say be the only real source of reliable energy. I’m not sure about Methane but liquid Thorium salt or similar perhaps

    I have considered radiation meteor strikes which may be a problem with no atmosphere to burn up particles.
    I consider caves or as you say Lava tubes as places where little resources would be required to fabricate and build structures that would be robust enough to protect against radiation and metors.

    This option gives limitless scope for expansion with little need to fabricate structures and engineer containment.Thermal regulation would be greatly enhanced either protection from heat or cold. This would vastly reduces the need for multiple fabrication processes that would be required to build complex and integrity resilient structures. This reduces payload drastically as well as cost. Most of the construction could be directed remotely or with limited equipment.

    The reflector concentrator I assume could be used to melt a tube in the basalt into say a crater face although I have my doubts that the structure of the crater walls are basalt Im no geologist or expert.

    Nitrogen will be a critical element in maintaining pressure integrity I would assume a sealed basalt or rock cave or tube treated by some form of coating would provide excellent integrity with little risk other than perhaps seismic fracturing if this is an issue.

    A tube with multiple air locks would provide excellent barriers and safeguards against failure. Tubes could be expanded with little more than excavating material that can be used as you say for production of materials perhaps directly within the excavated deposits.
    This of corse would depend on geology and stability.

    Food production would depend on supplementing sunlight daily to compensate for long nights some form of alge based food perhaps ideally we would want to grow something more palatable and provide some simulation that allowed for plant growth to remind us of home.
    I worry that this would be a community more for the scientific community or as a temporary place to live rather than people wanting to live there permanently when earth would be the alternative.

    If we are talking of a stepping stone to inter planetary exploration That would defiantly work if we could establish a space industry that had the benefit of fabricating spacecraft with less constraints on size capable of escaping the earths considerable gravity.

    Resupply from earth would provide recyclable plastics which could be used in 3D printers to fabricate components. Recycling everything would be critical.

    I look forward to more of your insights.

    Sam

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    1. There is a lot here to respond to. Some of what you mention is covered in posts on the forum of the website - some of which was copied to this blog when i started it a couple of months ago. I would also recommend going through the markers in the 3d models on the website, much of what you have asked about is explained.


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    2. Thanks Kim I will look in more detail I have looked here only a lot to cover Solutions to problems is a passion. I have worked in habitat control for over 30 years mainly in Subsea and enclosed surface units under pressure life Support. I have looked through the markers I think most of them my internet is very slow at the moment as Im on a ship with 18 divers living in chambers under pressure. Thank you for your response.

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    3. That sounds like a great job. Sorry to be replying so late, i must have gotten caught up in something else and forgotten. You contacted me at a very busy time.

      Let me clarify a few things. Nuclear thermal rockets work by heating a fuel to very high temperatures very quickly and releasing the vapor out the nozzles. The back end of such rockets look the same as normal chemical rockets, with hot vapors jetting out nozzles. Hydrogen is the most efficient fuel for NTRs. The methane is an efficient way to ship hydrogen in this case. Shipping liquid hydrogen comes with a lot of problems, and though 3/4 of the mass of methane is carbon, that's a very useful chemical you'd be shipping anyhow. Thorium salt reactors would indeed be the best thing in the long term, as Lalande crater is a hotspot of thorium.

      Lava tubes have been considered a lot, because large ones are known to exist on the Moon. I'm not focusing on them because i don't think many people would want to live in a cave long-term. There are other solutions to radiation and meteoroids - and at any rate, we will definitely have to build most things outside caves. They aren't going to be where we need them most of the time. There are other solutions to radiation and meteoroids that work better, they just need more infrastructure, which is exactly what we are going to the Moon to create, right?

      There is some seismic activity on the Moon. Moonquakes are not very intense but it has to be assumed cracks are going to happen sometimes in habitat walls. Cracks are easily sealed by applying a thin coat of basalt lava. Finding the cracks may be the most difficult thing, but it isn't hard to simply re-coat large areas.

      The dark areas of the Moon are all basalt. Lalande is on the edge of one basalt 'sea' and it is quite possible parts of its walls will be highlands materials with a very different chemistry.

      The further you send sunlight down fiber-optic cables, the less comes out the other end, instead being lost as heat along the way. I really don't know what distance is reasonable for such a device. I'm working on a version that uses a straight sapphire rod to do the boring and reduces the number of times the sun is reflected before being emitted at the other end, that should help.

      So there are a few things covered. I have to focus on writing up documentation for all this kind of thing on the website and i don't always have time to respond to comments for that reason. I have only one collaborator right now, and he can only help with certain things. I'm really swamped most of the time.

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