A City on Mars: Reality kills space settlement dreams
arstechnica.com
arstechnica.com
However, I disagree with their assertions that international law will be a significant hinderance to space colonization. The Outer Space Treaty[1] and similar arrangements are basically modern-day equivalents to the Treaty of Tordesillas[2]; they will be ignored or "creatively reinterpreted" the moment that someone sees something to gain. The Artemis Accords[3] are already arguably an example of the latter. To quote Francis I of France: "The sun shines for me as it does for others. I would very much like to see the clause of Adam's will by which I should be denied my share of the world."
[0] https://en.wikipedia.org/wiki/Controlled_ecological_life-support_system
[1] https://en.wikipedia.org/wiki/Outer_Space_Treaty
[2] https://en.wikipedia.org/wiki/Treaty_of_Tordesillas
[3] https://en.wikipedia.org/wiki/Artemis_AccordsDo we not already have a culture willing to maintain culinary water systems, sewage, the electrical grid, etc? Sure it's not as bad if one of those goes offline sad with life support but we pretty well can and do take for granted that those things are always there. And pretty rarely are any of these offline everywhere in a given area. There's plenty of redundancy.
Speaking of which, no doubt some thought will be needed for non Earthly natural disasters.
The Earth and its ecology is a life support system - it’s the only one that’s ever existed for longer than a human generation or two. Though human maintenance is not required - we are inherent to the system - we’ve nonetheless rapidly figured out a way to break it so grievously our own part in it is endangered.
- shifting ice moving at different rates on a the ice cap and even more so on glaciers, and legally we consider it a protected environment we explicitly don’t want to colonise
- the oceans is corrosive, plant and animal life is everywhere from biofilms to barnacles your stuff is going to become covered and anything left open or closed for too long without extensive cleaning and maintenance will become a slightly different shape than you think it is… and that’s a problem due to the crushing pressure required to make use of all but the shallowest waters, so shallow there’s not even really that much of them… otherwise your past 100m and ten atmospheres of pressure and it’s not only challenging it’s make mistake and die instantly challenging, you go deeper to get more “land area” and those extra atmospheres will turn a pinhole leak into a knife made of water even if the structure remains intact while filling with water… it’s not a great place to be when things go wrong… short of insane over engineering things like giant thick steel spheres (thickness obviously depending on depth) we would be also dealing with breathing pressurised atmosphere to minimise the pressure differential between inside and out… it’s just all around a lot harder to utilise most of the earth’s ocean floor.
- the worst the moon can throw at us is radiation, a 1 atmosphere “pushing out” pressure differential and very nasty dust… all of which have simple enough engineering solutions that we routinely build equipment using on earth, clean room style “high” pressure (not really that high just enough to dislodge stuff) blowdown entry systems (which could be way more powerful if your in a spacesuit… would easily handle the dust and worst case use the decontamination shower approach, we found ice, there’s water, use it to avoid the bad dust getting in. As for the radiation we’re exposed to a bit of it normally, there’s a little less in the magnetotail and earth shields it a bit and between limiting surface time per week/month/year and digging habitats underground you get well below safe limits… the digging also simplifies the pressure differential and even without it, we’ve been making spaceships for decades and industrial pressure vessels that can take greater pressure differential for over a century…
- mars has less of a pressure differential, less solar radiation due to square cube law, and peroxide rich soils. Well chemistry is a pain but industrial chemicals get made and we know how to manage cleaning processes and decontamination for anything I’ve seen listed in the Martian regolith at least. The radiation can be solved just like on the moon the same thing goes for the pressure differential.
It’s not a matter of technology, it’s been a matter of cost per ton to low earth orbit since about the 1970s… or the 2000s when we finally got our heads around some of the non-biological “closed loop” O2/CO2/H20 life support technologies, capturing the CO2 , breaking it to CH4, getting back the O2, getting H2 and 2 O2s from the H2O and balancing all this with systems to vent or otherwise utilise excess H2 or CH4, did take us a bit longer… but with a low enough cost per ton it could have been done earlier, logistics are logistics, be it fresh fruit products on a train from Florida to NYC or the fleets of trucks that bring food into inner city London, we live in a world where a significant portion of the population are no where close to self sufficient and are reliant on the operation of logistical chains that bring them what they need to live without having to move closer to food producing regions. Space would be no different, 3-7 day transits for quite a lot of fresh produce to stores are tolerable if less than ideal (faster is always better) and that’s perfect doable to the moon, mars would need us to step up our agricultural game a bit but if we ship up soil by the ton and we have water, we can make a greenhouse in a box and the plans will be fine anywhere, and some fresh produce would even be able to make that sort of trip, and industry on the moon could build things like long magnetic track launchers that could get cargo up to velocities where the transit to mars is weeks if you built the launched cargo units so you could give them enough fuel to decelerate in time (at that speed your not aerobreaking in mars’ atmosphere that’s for sure)
Regarding your last suggestion, what you actually want is a skyhook to catch the payload, with Phobos at the center. You can even use Phobos regolith to manufacture the basalt fiber required to build the cable.
Respectable background.
> the only clear evidence for how space affects humans is weighted quite strongly against going. That balance could be changed by doing the work to discover the answers to some of the questions posed in the book... So, maybe do the work beforehand?
This is also something which sounds very reasonable.
> I was shocked to learn that no one really knows how to construct a long-term habitable settlement for either the Moon or Mars.
There were serious, funded, government-sponsored plans for Moon bases over the last half a century. Many kinds of experiments run to answer some specific questions. Definitely not all questions got an answer - but I still think to say "no one knows" is overstatement.
First, we're all living in space. Earth is in space. We're all separated from space by some 100 km - a somewhat arbitrary boundary - of literally thin air. So talking about "living in space" we usually mean "not on Earth". Some of us have lived for months on space stations - and came back in rather livable condition. So we can't say that space kills immediately no matter what we do. Usually we talk about such longer-term dangers as different gravity and too much radiation. Of course air, water, food are also needed immediately, but we've had such problems when we developed e.g. underwater transportation, so we have some solutions.
It's true we don't have good experience with different gravity levels. Space stations are the environment of weightlessness, which is somewhat well studied and found rather unhealthy. But nobody lived for any prolonged time in Moon gravity, even less so Mars gravity, or artificial gravity of any level, which could be achieved in livable modules on centrifuges. It's a sad situation that many scientific demands require expensive space stations to keep microgravity environment, so we can't actually study - scientifically, with experiments - the medical effects of artificial gravity. Maybe we'll have rotation space stations soon, when costs for that hopefully decrease.
From what we thought and planned for artificial gravity, it looks feasible to achieve Earth-like conditions in an orbital station - possibly large, but still achievable - or on the surface of the Moon or Mars. We don't have enough data, but theory and plans are such that to say that "no one really knows how to construct" such a thing needs some clarification. Perhaps https://ssi.org/ may help.
Regarding radiation, we do think we can recreate the effect of the Earth atmosphere in a more permanent settlement. Orbital station has to probably be big and expensive - well, everything in space is expensive - but maybe on the Moon surface the radiation shielding could be more easily achievable. Yes, that doesn't look too similar to how we used to live on Earth - but it could be an achievable solution for time periods longer than those months on the space stations with, as expected, better results regarding radiation exposure. So, again, doesn't look like a scientific problem with an uncertainty if it could be achieved at all.
What we do lack is engineering, which requires more money than we had so far. Things slowly change in that area though, so we might take another attempt in engineering solutions in this and subsequent decades.
Can we confidently say that reality kills space settlement dreams? That's still a good question, but we don't seem to have a good answer now.
If we can figure out how to put a sustainable society on Mars, why not Earth first? That would be 100x more economical and less risky.
The terra-forming project is the all-time ultimate hubristic engineering project waiting for funding that goes far beyond biblical proportions in both cost and odds against success.
I think that is THE main problem. Once we all agree, there will be money put to this and problem will eventually be solved.
About that, I wonder if you can't build a local magnetic field to protect you from radiation. With the much lower gravity and very thin atmosphere and no seismic activity, it should be fairly easy to build ultra-tall antenna-like towers, like hundreds of meters tall. You can then put some cables between them, pass some high voltage potential, and maybe you can deflect the cosmic rays enough to keep a certain area more or less radiation free. In that area then you put some pressurized tents, and you don't need to live underground.