Conscious Choice cover

From the press release: In this ground-breaking new history of early America, historian Robert Zimmerman not only exposes the lie behind The New York Times 1619 Project that falsely claims slavery is central to the history of the United States, he also provides profound lessons about the nature of human societies, lessons important for Americans today as well as for all future settlers on Mars and elsewhere in space.

Conscious Choice: The origins of slavery in America and why it matters today and for our future in outer space, is a riveting page-turning story that documents how slavery slowly became pervasive in the southern British colonies of North America, colonies founded by a people and culture that not only did not allow slavery but in every way were hostile to the practice.  
Conscious Choice does more however. In telling the tragic history of the Virginia colony and the rise of slavery there, Zimmerman lays out the proper path for creating healthy societies in places like the Moon and Mars.


“Zimmerman’s ground-breaking history provides every future generation the basic framework for establishing new societies on other worlds. We would be wise to heed what he says.” —Robert Zubrin, founder of founder of the Mars Society.


Available everywhere for $3.99 (before discount) at Amazon, Barnes & Noble, and all ebook vendors, or direct from the ebook publisher, ebookit. And if you buy it from ebookit you don't support the big tech companies and I get a bigger cut much sooner.

3D printing of bricks, using moondust

European engineers have managed to print bricks using simulated moondust and focused sunlight.

The resulting bricks have the equivalent strength of gypsum, and are set to undergo detailed mechanical testing. Some bricks show some warping at the edges, Advenit adds, because their edges cool faster than the centre: “We’re looking how to manage this effect, perhaps by occasionally accelerating the printing speed so that less heat accumulates within the brick. But for now this project is a proof of concept, showing that such a lunar construction method is indeed feasible.”

The video at the link is very unconvincing. While it shows film of the printing process, it does not show film of anyone holding or manipulating the finished bricks. Instead, it shows one or two photos of finished bricks, all of which give the impression that these bricks crumble easily at the edges, I suspect that the bricks are simply too fragile for practical use.

So, is this a proof of concept? Maybe. They have at least shown that 3D printing using materials on the Moon might work.


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  • Garry

    It might be worthwhile to investigate coating the bricks with something to hold them together better. There might be value in using the moon dust to bear the compression load, with the coating holding the bricks themselves intact.

    I have no idea what that substance might be; it would have to be very cohesive, require only a thin coat, and allow bonding to whatever is going to serve as the mortar. Perhaps the coating could be applied by 3D printing. Of course, it would also have to be usable in a vacuum, withstand extreme temperature changes, etc.

    This looks like the first of what may be a huge number of steps before anything practical is realized. We have to start somewhere.

  • LocalFluff

    As an experiment it might have been successful, depending on the requirements. But in terms of spaceflight it is not helpful. All components used in spaceflight are pretty rigorously quality checked. This brick which looks like a brittle piece of [deleted] doesn’t fit in. Building a Lunar colony using this stuff, that won’t happen. It is very important to study how Lunar resources can be made useful, I love these guys and envy their jobs. But they should wait with publishing their results until they have any. This didn’t work.

    Just a few hundred yards from my home, there are cows who “3D-print” bricks like that every day.

    About 24 minutes into this video (sorry for the horrible video player they insist on using at SSERVI), an experiment is mentioned, in a passing way, that concentrated sunlight on Lunar regolith in an artificial methane atmosphere. Solid iron just pops up out of the ground! Solid metal is much easier to handle than any ceramics. Our Moon is an iron Moon! Exploring it will dawn the second iron age.

  • LocalFluff: Watch your language! I do not tolerate cursing or four-letter words on Behind the Black. Do it again and I will be forced to consider banning, even though I would regret it.

  • Cotour

    I might tend to investigate the simple processing of the moon material and flowing that processed material to a CNC controlled head where solar panels would also drive a high powered Laser delivered through a flexible fiber optics cable that would do the bonding of the material into what ever exact shape was needed.

    Although this is a more complex solution I think it might be faster and achieve better quality control. Sometimes the simplest solutions are just too simple. This technology seems too simple to me.

  • Cotour

    Something like combining this:

    And this:

  • LocalFluff

    I’m sorry, Robert. I will use medical latin when describing what this ESA brick looks like. Out of respect for all the children who read your blog.

  • wayne

    Garry– for my money, it’s going to have to be some sort of imported plastic derivative, which gets mixed with Moon “dirt,” and is able to bind it together & react with it, with minimal additional processing.

    They might want to re-define what they call a “brick.”Let us not forget, “bricks” have to be fired to chemically fuse together. You mix a pre-screened clay type mineral together with water, which has to be extruded into a mold to form, and then energy must be added to complete the chemical-reaction. Load-bearing bricks don’t “dry,” they have to be fired.

    Brief History of brickmaking in the United States
    (with links to modern day manufacturing techniques)

  • LocalFluff: The reason I demand courtesy and good language is to force the commenters to raise themselves up from animals and savages. If someone can’t behave like a civilized and thoughtful person and has to descend to curse words and insults, then they really don’t belong here.

  • Cotour


    The challenge is to process the existing material on the moon or where ever you happen to find yourself. To create a system that needs any raw materials imported to the moon, or an asteroid, from the earth is a non starter. Turn solar power into electricity in order to extract Water / Oxygen / Hydrogen etc. and then using the electrical power producing ability to drive machines I.E lasers in order to melt and combine the materials found on site is the winning model.

  • wayne


    Autarky will, of course be a long term goal for Moon settlement. You do however triage vital implements/resources and bring them along, whether it’s across the Great Plains or Space. As you establish indigenous capability, you can import less.

    To say however, that *any” imported raw materials required, would be a non-starter, is to understate the problem.

    Referencing electricity requirements for any sort of industrial-process at scale; solar panels aren’t up to the job. Making aluminum for example, is electricity intensive.
    And most common chemical-reactions don’t occur at ambient Moon (or Earth) temperature.
    On the upside however– the vacuum of the Moon presents a number of advantages.

    I’d prefer to “make brick on the Moon,” with the lowest level of technology that can get the job done, and I’m doubting that involves laser’s, which would have to be imported as well.

    But, who knows? -I don’t claim to have the solution, I only play a Materials Engineer, on the interweb.)

    and..trying to be cognizant of the First Rule of Space Advocacy, “You aren’t allowed to rain on other people’s parades.”

  • wayne

    Correction– I can see laser’s finishing bricks, but just not in the medium/short-term.

    I’m thinking more 1st/2nd-generation local (Moon) manufacture of such items, on a survival/establishment basis.
    The brick might not be the best building material format to conceptualize for the Moon. We would also need a Moon conducive method to mortar the bricks together.
    –My house basement & foundation for example, all poured concrete. Cool & quick process– dug the hole, set up forms & re-bar, and pumped a slurry of cement into them.

  • Edward

    For those who think that this test is a failure, notice that a lot of information has been gleaned from the test.

    It has shown that the concept of concentrating solar radiation to heat the material into some form of construction material is likely valid, rather than depending upon electrical generation.

    It has shown that at the temperatures reached, merely heating lunar regolith in place will not create the lunar roadway surfaces that have been envisioned by some. It has not answered the question of what temperature is needed for this road-building process, or whether this process is feasible.

    It shows that lunar soil can be formed into construction material of some amount of strength, although a greater strength or reduced friability may be desirable for construction.

    Garry is correct. This is only the start of the investigation into practical lunar construction using in situ materials, rather than materials lifted out of Earth’s gravity well.

    Cotour is correct. Just as on Earth, local materials are the least expensive to use for construction. I recall driving on a highway that has a pink hue, in northeastern Minnesota, because that is the color of the local rock.

  • Cotour

    I think that the concept of the “brick” is more an earth type construction modality. The manufacture of a brick and then the manufacture of some other material to adhere it to itself is IMO a non starter. And when you take into consideration the extreme variation of temperatures, low gravity and the problem extracting water and hydrogen from the existing local material I think the go to building model becomes the CNC / scintered / robot construction solution.

    These structures will be made by planting a complete manufacturing system package which will have solar and probably some sort of “safe” nuclear power generation system (or an ECAT?) on the surface of the moon. I assume initially they will be complete inflatable enclosures that could be covered by local material for protection and then there will be enclosures dug deeper into the surface that will be more complex and made in one complete sealed and bonded enclosure. And then there will be the tunnel potential, if they are determined to be stable.

    We will have to bring some level of material initially but the goal will always be to develop on site manufacturing capabilities both metals and ceramics, gases and liquids. These robots will be flown to a location and will autonomously set out to build these sites readying them for human inspection and habitation.

  • wayne

    –I’d like more information on “the CNC / sintered / robot construction solution.” And what materials are going to be transformed by what process into what useful building material, for what end-purpose?
    –When did we invent all these autonomous robotic manufacturing processes?

    I’m seriously doubting initial settlement of the Moon is going to take the form of 2017 America, with sleek, brushed-aluminum interiors, back-lit by Solar FREAKIN’ roadway technology lights.

  • Max

    I’m not impressed, I’ve seen better bricks made with a drop Forge. I’ve made better blocks out of salt in a 50 ton press for Cows.
    3-D printing has many uses, but bricks for the moon? I don’t think so. overkill, waste of resources.
    Wayne said, “lowest levels of technology that gets the job done”. I agree. We have hundreds of years of casting technology that could make an entire dwelling with one pour. I have a magnifying glass 2′ by 18 inches that can melt thin metal, or melt patterns on bricks.
    It would only take a few mirrors to reflect the raw sunlight on a crucible made for space that could pour out the entire dome shaped building suitable for habitation within hours.
    The crucible can be made from iron pulled from the surface with nothing more than a bar magnet. Modern crushing and or separation would occur after the Infrastructure has been created. Bricks would be a temporary support for the infrastructure, not to live in.
    If they can melt sodium in the California desert inside a atmosphere, melting regolith into glass on a airless low gravity moon should pose no problem.
    The airlock would pose a more refined problem, perhaps the 3-D printer for precise fit would be a better application.

    For power, a simple steam generator would be self-contained with proven technology having off-the-shelf reliability and low maintenance. The temperature in the lunar sun is 250°, just enough to boil water that would otherwise be sitting in a storage tank somewhere.
    When the sun goes down for 14 days, perhaps it would be better to be underground and insulated against the 300° below zero temperatures on the surface.

  • pzatchok

    I still say the fastest way to construct habitats on the moon would be by large amounts of manpower.

    Drop onto the surface temporary shelters that inflate. Bigalow can provide these today.
    Someone has to go up and flatten the ground with ‘earth’ movers so larger structures can be installed.

    I truly think a thinner than normal Bigalow dome could be the form for a spray coated concrete liner.
    Using gravel sized regolith as your aggregate would make the concrete cheaper to produce and most of the water would be recovered during and after the curing process. A simple dehumidifier does the water recovery so it can be recycled into the next load of concrete.

    As your permanent domes are hardened and finished just cover them with several feet of sand sized regolith for further micrometeorite protection.

    Connect the domes with flexible tubes in case of lunar quakes.

    The brick idea is fine. But in order to not use a hardening mortar you have to shape the drinks a little like Lego blocks. A pair of ‘posts’ on the top of each brick and a pair of sockets in the bottom of each brick. Sand in between each brick.
    The bricks would not be solid but would float a little.
    You could shape the bricks so they form arches and domes better.
    You could form arches over the flexible rubes and then cover those arches with regolith.

  • wayne

    pzatchok– that’s the type of thinking I favor.

    (The least processing one can get away with.)

    pivoting slightly–This is an intriguing methodology: “Earth-bag” construction.

    Underground Earth Bag Building Ep 3
    Building Considerations – Strengthen the Walls

  • Edward

    There is no need to be fancy with the early lunar construction. Near San Francisco is the “Flintstone House,” built fairly simply, and people actually do live in it.

    The point being that what seems funky can be functional.

  • pzatchok

    Thats pretty much the same as my idea.

    Except that cement is a little porous. So air will escape. Plus it might crack during curing and or drying;

    So my idea keeps the sealed dome bag on the outside. Plus my idea lets you recover as much as possible of the valuable water.

  • Edward

    My intention was to support your thinking. However, I do not think that large amounts of manpower is needed, as robots or remotely controlled machinery could perform most of the work before people arrive.

    I had been thinking of sealing the interior, but your idea of recovering as much water as possible is good.

  • pzatchok

    Robots are a nice safe idea but they just do not have the intelligence to layout and prep a sight for building.
    Plus robots will not be able to make field repairs on any of the equipment.

    We barely have self driving cars now. When we have self driving semis that refuel themselves and load and unload themselves then we MIGHT be close to having automated construction machines.
    On earth but not in the remotes of space.

    Man will pave the way for robots.

    Manpower and intelligence is ready today.

  • ken anthony

    It just seems these ideas are not by serious people. Will the habitats they build on the moon be vacant? If not, then humans will be around to do the construction that follows. We don’t need robots to build anything. It’s easy enough to transport the first habitat along with the tools to construct more.

    We need to get material engineers (and not) on the moon and let them play. Allow people to own what they build and the optimum methods/designs will soon rise to the top.

  • PeterF

    Anybody notice that Elon Musk is starting another boring company?

  • Edward

    ken anthony wrote: “It just seems these ideas are not by serious people. Will the habitats they build on the moon be vacant?

    Wouldn’t it be nice to have a habitat to live in when you first arrive on the Moon rather than spend a month living in the cramped lunar module while you build your first habitat? With enough adaptability in your robot or remotely operated machinery, the machines should be able to work around problems that come up — and problems always do. They can spend weeks or months building facilities before people arrive.

    The discussion had moved away from the idea of sending a prefab habitat for the first mission crew (missionaries?) to the idea of laying brick or concrete, using in situ materials rather than expend the resources moving all the materials from the deep gravity well of the Earth. Either way, it would be more productive for the crew on the Moon to be doing science and other things that are not as repetitive as construction or brick making. It costs a fortune to put people on the Moon, so they might as well be productive in ways that robots and machinery are not.

    I suspect that the reality is that first-generation habitats will be sent to the Moon from Earth, requiring minimal construction effort, second-generation habitats will be made with in situ materials, and third-generation habitats will be made with more advanced refining of in situ materials and more advanced construction techniques.

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