To be honest, I'm still hung up on the lack of viable radiation shielding, a way to protect people from the harmful effects of microgravity, and micrometeorite impacts. I don't doubt that given time and experience, payloads can be sent to Mars, I just doubt that functional, healthy humans can be under this kind of scheme.
The amount of radiation received on a Earth-Mars trip gives a cancer risk roughly that of being a smoker. Not awesome, but certainly survivable. Plus, a hundred people's worth of water stored in the walls should make a pretty nice shield (not to mention the propellant tanks, which they plan to aim at the Sun to absorb the brunt of radiation).
People already stay on the ISS two to four times as long as Musk's proposed travel time to Mars, and they'll be landing somewhere with a third of Earth's gravity. They might all need to hang out for a day or two to get their Mars legs, but I don't see an issue here either.
Micrometeorite impacts haven't done the ISS any appreciable damage in its nearly 20 year service history. Again, doesn't seem like a problem.
And as missions become routine, costs drop, and dangers become well-known all of these things will only improve. The biggest obstacle to making space travel more human-friendly is that practically no humans are traveling through space. Change that part of the equation and the rest is downhill.
It's not really the trip that worries me, it's living on Mars. You need to live under five meters of soil in order to get the same radiation protection as Earth's atmosphere provides. You're basically mole people. Which means the difference between living on Mars and living in windowless apartment complex on Earth is that you can do a couple space suit jaunts through the Martian deserts each week.
People can definitely survive living almost entirely indoors. I expect VR will be big on Mars. But I think the lack of natural light will really limit the comfort level.
If someone can invent an invisible electromagnetic radiation shield that would change the game.
Is EM radiation that can't be blocked by sheets of metal really an important problem? It looks like we can use magnetic fields to block charged particles and apparently that's good enough for space travel - but perhaps not for a person's whole life.
Sheets of metal have a lot of issues, unless you bring hugely THICK sheets of dense metals. All you do with thinner shielding is turn your alpha/beta risk into a re-radiated gamma risk. Plus, dense shielding is heavy... and therefore expensive in terms of its Delta-v.
Artificial light isn't the best, but it can be made to resemble daylight; I don't see that as a show-stopper.
If we can find some nice lava tubes that can be sealed and pressurized, it might make for some rather spacious dwellings. But yes, I expect the first Martians to effectively be mole people.
I imagine living on Mars would be a lot like living in a place like Whittier Alaska [1] (a town where everyone lives in the same building). Not for everyone, but some people might like it.
I doubt that's the case. Suits will be tough, and undoubtedly come with patch kits, and folks will use the buddy system.
A penny-sized hole would give time to patch, and suits would likely be designed to compartmentalize in a leak. In a true worst-case scenario, chimp studies in the 1970s showed they could survive several minutes of total vacuum.
How long a human would survive is one thing. How much medical care they'd need is another. They'd be on Mars, not Earth, and I imagine being a quadruple amputee on Mars would effectively be a death sentence.
People have lived in zero g for a year at a time, without significant health impact. The SpaceX proposed transit of three months is a quarter of that.
These year long stays were on the space station, which has similar or less shielding. The Earth's magnetic field helps, but really, by the time you get to your Mars habitat with unlimited shielding mass available, your total dose is not that high.
If you have a 5% of dying in transit or at Mars due to equipment failure, as well as a 2% increased chance of getting cancer at some time in the future, the first obviously is the one to worry about.
It's going to be dangerous enough on Mars, without adding those factors in. Worse, it's going to be difficult if the person who dies is in a critical position. You would have some redundancy in personnel, but that's costly in terms of Delta-v too, for them, and for everything it takes to keep them alive.
The effects are really pretty bad after a year and significant even after 6 months with exercise. That's why it was so important to get the transit time down to 3 months.
You really want a pretty large diameter so that you don't have a huge gravity gradient causing your astronauts discomfort. Tethers might be more practical than the classical doughnut designs for the near future.
JAXA recently brought up a small wheel into the ISS that can be used to simulate varying levels of spin on mice. Research into .4G gravity is particularly important if we're going to be sending people to Mars, but in general if lower levels of gravity keep mice and people happy those'll be easier to generate on future spacecraft.
Would make a great TV series, a la Terra Nova. You might have a society where the average lifespan is cut in half, predominant diseases are space-related and accidents are a daily or weekly part of life. It wouldn't be like living on Earth, but it would be something.
You might enjoy The Expanse book series! There are several world-building tangents that delve into exactly this area.
I'm thinking (no spoilers) specifically of how Ceres, having been spun up to provide artificial gravity, becomes a destination for expecting mothers trying to avoid complications associated with low-G.
I also like how the only sci-fi conceit the book asks for (besides the antagonist aliens obviously) are the engines which are right on the edge of the theoretical maximum.
The SpaceX Mars architecture: it is the answer to an unknown question, an artifact from the future time traveling back to the present. The objectives and constraints that were used in the design process are not revealed. It is like Phouchg and Loonquawl getting the answer 42 from Deep Thought. People generally have no clue what to make of it.
I'd guess that if the objectives and constraints used in the design process were revealed, it would all make complete sense. Elon has a track record of making technical and business decisions that turn out to be 100% correct in retrospect. The epic size of the vehicles are a feature, not a bug, for instance.
Musk has been surprisingly silent (or has seriously downplayed) on the radiation question, which is a pretty big deal for travel beyond earth's magnetosphere.
But here's the thing, IMO: Musk is offering ITS as a transport facility, nothing more, nothing less. If you have payload (a living human) that is fragile (sensitive to radiation) you bring your own extra styrofoam (you include weight of shielding water or lead or what have you as part of the payload).
But if he says that out loud, it'll hurt the momentum of the movement.
The idea of the $200K ticket price is only once the system is mature and well-tested. The early trips will have to cost a lot more. Probably a lot more than $10 million a seat.
Early trips would of course not have a large crew, since they'd be mostly focused on setting up a base, and be more about cargo and equipment. Saying "several tens of millions" is because that's generally what it costs right now to get someone to low Earth orbit. If we can get early trips to Mars down to what it would cost for a current orbital mission, that would be very impressive.
The graph he's showing at the point you linked to shows the max cost around $550k to Mars, which fits with some extremely simplified ballpark math for making the trip efficient:
Start with ~$30 million (based on "several tens of millions") to get a person to orbit using current tech. Current tech doesn't use reusable rockets, and the cost of building a rocket greatly exceeds the cost of the fuel for the launch, so we'll assume fuel costs are 0. If you make a rocket that you can reuse for 10 launches, your price tag is down to $3 million to get a person to orbit. The next step is to make a bigger rocket: currently the Soyuz rocket is the only rocket taking people to the ISS (assuming this is roughly what you mean by getting someone to low Earth orbit), and it can only take 3 people at a time[0]. If you make your reusable rocket big enough to take 100 people at a time, your price tag goes down ~33x to $100k to get a person to orbit. Of course, a bigger rocket will probably cost more to make than current "small" rockets -- but a big reusable rocket would have to cost 330x more to build than a modern small rocket for future seats to cost ~$30 million per ticket.
So even the first trip to Mars should be well under $1 million per person as long as they make the rockets big and reusable.
Right, the challenge is mainly that the first missions will have to carry a lot of cargo (priced into the cost of sending the crew) and that it'll be easier to bear the cost of development and construction if the early missions have a higher price.
Even if the cost for the first few trips was $50 million per person, there'd be no shortage at all of people who would be paid for by governments or organizations with that kind of money. Might as well use it, and apply these funds to expanding the program.
Full reusability is really the essential part of this system - you can't afford to throw away any stage of a rocket this big. Fortunately, the larger the vehicle, the easier reusability tends to be (up to a point of course).
Well, there's only so many people you can fit onto a rocket of a particular size. And eventually increasing rocket size gives you diminishing returns, so there's an upper limit. Once you've used a rocket a few hundred times, though, most of your costs become things like fuel and oxygen, pad maintenance, and rocket refurbishment.
There are practical limitations from engineering and economic perspectives. From the engineering standpoint, architectures tend to run into scale problems as you make things bigger.[0] For example, if you take an existing rocket design and decide to make the same thing except 25% taller, while keeping the other proportions the same, you'd actually increase the mass of your rocket by a factor of 2 (width and depth also increase by 25% -> 1.25^3 = ~2). From the article I linked to, breaking strength varies with cross-sectional area rather than mass, so the rocket's breaking strength would only have increased by a factor of 1.56. So your rocket design might no longer be sturdy enough, and it might warp or break or explode when you try to launch it. (Breaking strength isn't the only factor to consider, either; there are tons of factors in materials science that would affect the many components of a rocket.)
The implication is that you'll probably want to design an entirely new rocket if you want to make one that's significantly bigger than what you've made in the past, because rocket designs aren't going to be fully reusable at significantly different scales.
That's where the economic perspective comes in: rockets are expensive, and the bigger they are, the more expensive they'll be, from a raw materials perspective at a bare minimum. The hundred person rocket that Musk has proposed would already be significantly larger than any actually constructed rocket to date, so it has to be a new design, which means they're going to have to build and test prototypes. And some of the prototypes will probably blow up during testing -- hopefully not many, or they'll run out of money and won't be able to keep going.
Now if you want to build a rocket that can hold a million people, you'd probably be talking about the largest man-made structure ever. The only structure on this scale that I'm aware of (which was never built) is the X-Seed 4000, which would have housed 500,000 to 1,000,000.[1] Its proposed height was 4000 meters, which is about 33 times taller than the proposed SpaceX interplanetary rocket. If you scaled up the SpaceX rocket design to that height, the mass would increase 36000x, and the breaking strength would only increase 1000x. I think we would probably need some major advances in materials science to be able to make a rocket that big that didn't just disintegrate on launch.
Secondly, what about the economics of a million person rocket? The X-Seed 4000 would have cost roughly a trillion dollars (in 2016 USD) to construct, and it just has to sit on the ground. I'm going to assume that at the barest, most insane minimum, it would cost at least 10x as much to build a rocket that size. So that's 1/7 to 1/10 of global GDP (in 2014)[2] -- for one rocket -- that will probably disintegrate.
But! Let's assume that we make major materials science advances and can actually make it work, and we make it reusable up to 10 launches, and somehow we get the whole planet to agree to build this thing. The price tag actually isn't so great... $10 trillion / 10 million people = a million dollar price tag per ticket. So maybe my estimate is too high and we could build a rocket that big for a trillion, no more than building a building that big. Even then you're still looking at $100k per ticket.
So, in short... My guess is that there might be some technological and economic sweet spots that are a bit bigger than than the SpaceX design, but I think it's a good starting place in terms of feasibility. And yes, in practice there are some limits to how big you'll make your rocket.
PS. I don't think "breaking strength" is likely the most relevant factor for rockets (I an not a rocket scientist), but it's the principle of the scaling thing that matters. Plus a rocket has to have supporting structures to help it keep its shape, so breaking strength might be relevant after all.
If I remember correctly from the presentation, Must claimed radiation was not a significant concern with the exception of things like solar flares. Can anyone comment on the accuracy of that?
Well, it's not nice out there, but hardly crippling. Cosmic radiation on the ISS is about 150 milliSieverts a year. Interplanetary space could get up to about 800 mSv a year. Not good, but if you can get there in, say, three months, then you've cut your exposure down to what an ISS crewmember would get in a year. The actual danger is solar flares, and for that you'll need some kind of shielding compartment onboard. The ISS is reasonably well-protected from those, but they'll really roast you if you're caught in interplanetary space.
I think Musk mentioned it somewhere in the presentation, but the initial plan for shielding if you're aware that there's going to be a solar flare is to angle the spaceship so that the engines are between the Sun and the crew compartment, and then have everyone packed near the water tank... or something along those lines (it might have been in response to a question in the Q&A time afterwards; I don't remember).
I don't know that they'll have this on the first trips there, but I'd guess that magnetic shields might eventually be a standard component:
Yes, I expect that more advanced active shielding will eventually be developed - particularly since you can detect solar flare events before the radiation arrives.
The challenge with flares is that the radiation can come in from multiple directions, so a cylindrical water container that people can pack into is probably a better defense than just the bulk of the engines.
I mean authors have been using that idea for years. The Red Mars trilogy for example (which was an at the time scientifically accurate example of mars colonization).
Each of the stuff for which we read here people jumping and yelling "visionary!" "revolutionary!" "unforeseen breakthrough!" "brand new plan!" "disruptive improvement!", has been dealt with dozen of times in hundreds of SF novels in the last 80 years, which explored all the possible problems (problems are a more exciting matter for a novel than everything-goes-fine-and-as-planned).
But since for most of those people, SF and anticipation is limited to Star-Wars + a couple of other movies/series and super-hero block-busters, they are not aware, and all these stuff appear as genuinely unprecedented technical and sociological thought breakthrough.
Perhaps that's one of the advantages of using a really big ship; you can put more shielding / water tanks between the sun and the passengers.
If it's a major problem, they might just orient the ship in a direction that gives the best radiation protection to the passengers and just leave it like that for most of the trip.
Robert Zubrin has been planning for Martian colonization for decades. He's like the Kurzweil for the movement, his Mars Society has been on a quixotic quest. Hopefully SpaceX hires him on as a consultant.
Absolutely. An even closer cooperation between the Mars Society and Spacex would be great. I am pretty sure though his critique will be studied quite closely by Spacex.
For Mars? I doubt it:
"It’s important to say that the idea of Mars as a lifeboat is wrong, in both a practical and a moral sense." ... "My feeling now is that faced with the extreme expense, technical challenge, and danger of going to Mars, interest is going to shift to the moon as a destination that can actually be reached and occupied during some of our lifetimes."
>Following the example of colonial America, let’s pick as the affordability criterion the property liquidation of a middle-class household, or seven years’ pay for a working man (say about $300,000 in today’s equivalent terms), a criterion with which Musk roughly concurs. Most middle-class householders would prefer to get to Mars in six months at the cost equivalent to one house instead of getting to Mars in four months at a cost equivalent to three houses.
Colonization of America was extractive. You send colonists and they survive on their own and even pay taxes and you get products back. That's not what would happen on Mars. There is nothing so valuable that it would be worth carrying back to Earth. At the same time it would take huge amount of money to support high-tech colony in Mars until it can support itself.
I imagine that the cost of moving people would be insignificant compared to the "colonization kit" that would enable the colony to become self sufficient. Developing that kit would probably cost more than all technology needed to move people to Mars. Just imagine the amount of technology transfer needed to build and maintain maintain systems for breathable air (air tanks, seals, valves, inspection equipment, instrumentation, automation electronics) without help from the Earth. Until Mars settlers can build things in-house, they need constant economic support from the earth.
ps. We don't even know how to sustain biosphere in closed environment yet.
I believe in the use of Mars as a sort of space-hub. It's better fit for this purpose than Earth, in many ways. It has less atmosphere, allowing for easier launches. Additionally, with around 1/3 the gravity, launches and landings are even easier. It's also closer to the asteroid belt, potentially making it useful as a sort of space mining hub and providing an economic incentive other than resources found on the planet.
That said, I am also doubtful. I don't foresee a trade-hub attracting 1 million people - if there are really a million people who want to go. Who the hell wants to risk their life and net worth just for the privilege of living on a rock less hospitable than Antarctica?
Ceres is a much better hub for mining asteroids or as an intermediate step to gas giants. Martian atmosphere is a b as the sad yesterday news show. Also less gravity. If you're going to need living in an underground bubble, look for the practical arrangements, not for the planet status.
Ceres isn't well-suited for long term human habitation due to extremely low gravity and a surface environment much more hostile than that of Mars. You'd either have to have a sizable rotating space station nearby or do everything with remotely controlled and/or autonomous robots, and in the case of the latter you'd be much better building the robots and/or space station on Mars and launching from there than trying to get all of that out of Earth's gravity well.
I took for granted that you would not use surface. The rotating station can be built inside a cave. The main advantage over orbiting is mining.
In other words, I believe that Mars' appeal is a mirage. Musk and company are seeing it as another Earth where people can live like here, with a little terraforming.
I think it would be much more difficult. Of course I could be wrong, or I could be right but, even then, Musk could be modern Columbus.
I would rather see the moon colonized than Mars. First, it has a resource that has economic value both there and here on earth: H3. Second, transporting that H3 would be cheap (as it's going "down hill" so to speak). There's also water, which makes it a bit cheaper to support a lunar colony. It's close by and we could certainly learn a lot about self sufficient support on alien worlds.
Not that people shouldn't go to the Moon, but there are a few 'amenities' that make Mars more attractive for a lot of people:
- Water and free carbon dioxide are hugely more abundant on Mars than on the Moon. These are essential supplies for increasing biomass and making fuel.
I think a lunar colony would be great but helium-3 isn't a good reason for one.
If you can get net energy by fusing He3, you can also do it by fusing deuterium, which is easier. And the end product of deuterium fusion is He3! (Half the time directly, the other half producing tritium which decays to He3.) So instead of sifting through millions of tons of dirt on the moon, you can just make He3 on Earth and gain energy in the process.
Deuterium fusion produces neutrons but they're lower energy than D-T neutrons. Fusion startup Helion (funded in part by YCombinator) is working on a hybrid D-D/D-He3 fusion reactor, and says only 6% of the output energy would be as neutron radiation.
"Additionally, with around 1/3 the gravity, launches and landings are even easier."
Launches, yes, but landings? Athmosphere is your enemy during launches, but your friend in landing.
Mars has an atmospheric pressure less than one percent of that of earth. That makes losing speed other than with rockets a problem, and that requires bringing lots of fuel.
In addition, the athmosphere that's there can be windy and turbulent. That can directly affect a spacecraft, but also causes dust storms that can make it hard to measure distance to ground.
Most of the cost of building a base on Mars is in the transportation. If it becomes possible to reuse the launch vehicles, then the cost falls. Ideally, it falls far enough that people (and sponsoring governments/organizations/companies) will be able to afford it on a pay-per-seat basis.
That's pretty much the whole of the economics. People and governments will jump at the chance to send humans to Mars, if there's a way to do it at a reasonable price.
The cost of the things that are necessary on Mars that will have to be shipped from Earth will be rolled into the ticket price. Hence the first few rounds of tickets will probably be quite expensive.
If you need to replace wheel on Mars rover or take a aspirin and you need to transfer it from earth, the cost will be enormous. Colony that can't support itself economically will collapse when outsiders stop supporting it. When the honeymoon is over, people don't' want to pay.
To make the colony self supporting, you need to transfer factories, chemical plants, machine industry, mining industry, etc.
I mean, it has to! You simply cannot build the kind of permanent presence on Mars with disposable rockets and ships, unless you have some sort of super-advanced Von Neumann robots that can be sent once and set it up on their own.
You need to transport a seed factory.[1] The clever thing about the Mars Colonial Transport is that it includes solar panels to generate electricity as well as the machinery needed to produce methane and oxygen which serves as fuel for a return voyage.
The really cool thing about this is that methane can be used as a feedstock to produce many plastics and the oxygen can be used for humans to breathe.
The MCT is a prototype for a seed factory style Von Neumann probe.
> Most of the cost of building a base on Mars is in the transportation.
How exactly do you know that? The only experiment about creating closed human colonies was deemed complete failures and not to be replicated due to ethical concerns.
A Mars colony doesn't have to be closed loop either. If you're bringing a large power source, you can make oxygen and fix carbon from the martian atmosphere. This is already part of the plan for the purposes of making fuel and oxidizer for the return trip.
Think of it more like a nuclear submarine with a greenhouse full of potatoes attached -- we can most likely do that.
Nobody's going to try to launch an entire mangrove forest on the first go. Biosphere2 is a failure of experimental design, not a failed experiment.
>Think of it more like a nuclear submarine with a greenhouse full of potatoes attached -
Maybe, but if we want to make Mars economically self sustaining the correct analogy is nuclear submarine that never surfaces and can totally self repair, including building new nuclear reactors and eventually replace all parts in itself.
They are not experimenting with sustainable biosphere. They eat prepackaged foods and are not completely sealed from their environment. They just simulate trip to Mars psychologically and test foods.
There was Biosphere 2 experiment few decades ago, but they could not keep the biosphere stable.
I'm skeptical of how effective a simulation of a trip to Mars would be.
There's just a huge psychological difference between knowing that you're in space, millions of miles from Earth or any kind of help and knowing you're in a simulation on Earth.
I suppose it's possible to fool people that they're in the former while actually being in the latter. But the ethical issues surrounding such an experiment would make it out of bounds for NASA. It might make for a fun scifi story, though.
Because building a base on Mars is going to require quite a high amount of mass shipped to the planet's surface, much of which will be simple supplies and materials, like food, solar panels, methane generators, and so forth. These things aren't expensive on Earth - they're just very heavy.
And a base on Mars will not be a closed system. It will continuously draw in raw materials from the surrounding environment. Mars is enticing for this because carbon dioxide and water are abundant, giving you the three most important elements for fuel and food production.
Yes but the ownership is open to anyone, so it's a lot easier for activist investors to change the mission to a more profitable one. Musk is keeping SpaceX private specifically to keep this from happening.
Worst case scenario, what would that actually be like? A few hundred people who gave up their lives on earth to live in habitats on an inhospitable planet one day learn that the worst fear of the 20th century came true, and there's nobody left back home. It's just them, the only remaining sentient beings in the known universe, without 99% of the technology that got them where they are now.
How could they even begin to try to rebuild civilization when they can't even go outside without an apparatus that took thousands of years of science to produce? What is the speed divisor for advancement of a society marooned on a world it didn't evolve to live on?
I'm all for Mars colonization, but as a backup plan for Homo sapiens, it kind of sucks.
A nuclear-proof bunker hidden beneath Greenland with air/water filter system will be 1000 times cheaper, and will promise a better survival chance in almost any scenario.
If humanity is wiped out on Earth, people in Mars are fucked anyway: they will be one depressurization accident from extinction.
If you don't think a space colony would have overengineered multiple redundancy against depressurization, you don't understand the psychological effect that vacuum being 6 inches away would have.
You need to think of it as a retirement community for well-to-do individuals with a desire for above average adventure. There are a lot of high net worth individuals on this planet.
And how many of them are seriously interested in going to Mars as early colonists? Maybe a handful at most. Consider how they got to be high net worth in the first place. A lot of work, a lot of risk. What for? I'd say for status and luxury. Things that they will lose if they go to Mars - living in cramped pressurized stations with a few dozen other colonists.
What if earth patents/IP were invalid on Mars? Wouldn't enterprises race to mars for the chance to code/manufacture components that they are legally and financially restricted from doing on earth?
>Until Mars settlers can build things in-house, they need constant economic support from the earth
This is where digital manufacturing (CNC, laser cutting, 3D printing) actually makes sense. You go with the base materials and blueprints, and you can survive without transferring goods. You manufacture on-demand, and the blueprints can change based on feedback/results. Mars SHOULD have a prototype culture, the same as with explorers. With engineering/research help from earth, a fab lab on mars would be incredibly valuable. Science the shit out of it!
Even is patents are invalid, when you bring they back to Earth they will be confiscated. It's like burning a pirate DVD in the middle of the sea and expecting to sell it legally in New York.
(And probably the transportation cost will be still high enough to make it mot profitable.)
>when you bring they back to Earth they will be confiscated
Nobody is talking about using Mars as a manufacturing base to transport to Earth, it's all about creating a self-sustaining colony. There has to be stronger incentives for people/companies to move there. Even on earth there are many economic zones incentivized by lack of regulation etc.
If Martian colonists can manufacture something using 3D printing, Earthlings can also do it, and probably a lot more cheaply, because all the necessary ingredient and parts (and even customers) are within forty light-millisecond, instead of ~20 light-minutes.
I'm having a hard time understanding this comment. That people on Earth can do it too does not detract from people on Mars doing it.
The parent comment isnt saying there will be an economy of building things on Mars and sending them to Earth, they're saying Mars can sustain itself without sharing an economy with Earth. Which I believe is true.
And for what it's worth, I'm actively working to build better robots with commodity 3D printers[1] and I hope to build self sustaining communities on Earth with 3D printed micro factories that produce all the goods humans need for survival.
I believe it is possible to make economically closed self sustaining communities. Both on Mars and on Earth. We've done it on Earth for a long time.
But why would a rational, self-interested person put up with great risk and expense to live in a small closed economy on Mars, when they could much more easily live in a small closed economy on earth? What's so great about Mars?
At our current technological level, we didn't even succeed in building a self-sustaining biosystem when we threw money at it (as a research project): see Biosphere 2.
Self-sustaining community that can economically fund itself is out of reach even here on Earth. And, frankly, 3D printing isn't magic: it won't help that much. Can you 3D-print a glass window that can withstand 1 atm and has anti-UV coating?
Sorry, where did I say 3D printing was magic? I'm a mechanical engineer who has had my 3D printer for 4 years. I just got a second one. I understand you can't print glass with a 3D printer. You can however, absolutely print critical parts of the machinery you would need to build a glass making system.
I'm talking 10-20 years out for having a self sustaining community that manufactures its own hard goods. But I believe it is possible and I'm working on making it real.
Well, I thought we were talking about building a Martian colony with 3D printing. Apologies if I misunderstood.
My (very uninformed) guess is that you could probably build a self-sustaining community using 3D printing, on the Alps or the Appalachian. (After all, our ancestors managed with stone tools.) Doing that on the South Pole will be challenging. Mars, forget it.
If you are persistent enough you could probably 3D print everything, I guess. Maybe you could 3D-print concrete and ceramic blocks to build a furnace that will be used to produce steel which will be shaped into a pipe (by another 3D printed machine) to transport hot gas to melt silicon oxide and produce glass.
However, after a few iterations, I guess people will ask "Why don't we just pour concrete over here in conventional way? That's much easier and cheaper."
Totally understandable, and I can see what you mean about 3D printing not being magic. You're not going to hit "print" and end up with completed pressure vessels ready to live in.
I do think, however, that robotics and additive manufacturing will be critical to building significant parts of the machinery and buildings on Mars.
Certainly, sometimes you will use traditional manufacturing methods to construct things. But additive manufacturing has different capabilities and it will be used for different things. And unlike some people who claim additive manufacturing can't be used for anything, I believe that a mixture of traditional manufacturing methods and additive methods will be critical to building a colony on Mars.
Imagine for instance that you want to build some buildings. Lets say both pouring concrete and additive manufacturing methods would work. You need to build 40 habitats. Would you rather work all day in a space suit in the hazardous near vacuum of Mars to build the forms needed to pour concrete for the structures? Or sit in your pajamas in a habitat on a computer designing and controlling the robots that will do it for you? And in that case, maybe you will want to have the robots make forms and pour the concrete for you, but perhaps you will use additive manufacturing methods.
I can imagine the latter is easier for robots, and using robots is easier for humans than doing the labor themselves.
Of course, to build a robot that will manufacture a home out of concrete, you need to build the mechanical parts of that robot. How will you do that? Probably not with CNC machines and blocks of aluminum (making such parts was my job for 7 years BTW). Instead I imagine that you will keep a library of feedstocks for 3D printing and you will print out the robot parts in your lab.
Interesting fact: there are now some extremely high performance plastics available for common home-style 3D printers, including carbon fiber filled PEEK. At $850 per kg that's a material I don't think you'd use unless you had to, but if I were building a colony on Mars at $500k a head I think I'd bring 100kg of that stuff.
100kg of carbon fiber filled PEEK plastic will make a lot of concrete extruding habitat constructing robot frames.
You'll have to bring the motors and electronics separately. At least until you build that foundry....
See what I mean when I say 3D printing can help make a self sustaining economy possible?
A lot of Seattle and San Francisco were built by supplying miners, and each other (Seattle did a steady trade of wood to SF).
If the real extraction happens on asteroids, then Mars or even the moon are a better base of operations just due to the smaller gravity well. And Mars isn't without its own mineral wealth. Several that would be important for growing food.
Asteroids near earth or diverted near earth can be economically sound but it's possible that mining nodules on the bottom of the ocean is more economic solution.
If you look at the delta-v map of solar system, everything massive like planets, is not going to be hub or center of extraction of minerals for other places. Mars would sit at the bottom of gravity well and be economical sink.
Deep space mining (robotic or semi automatic) of asteroids can be economically viable, but just few relatively small asteroids would provide Earth or Mars for centuries.
But raw materials are not enough, you would need industry to build all stuff you need and maintain it. If you can't manufacture 3D printer or CNC milling machine by yourself, you need to buy it from Earth. Just being able to make cast iron is not enough, you need high-tech equipment and manufacturing for them to survive.
Making Mars self sustaining circular economy would be massive systems engineering challenge.
I think if the cost of sending people to Mars really did fall down to those estimates, then countries themselves will try to send colonists, only because if they don't, and others will, then they will "miss out". Imagine if China insisted it wanted to send 10 000 of its people there? I'll wager europeans, americans, russians and indians will want to send at least as much, just not to be exposed as "weaker". It'll certainly be a factor in their decision making at least.
> SpaceX has no prospect of being able to afford the very large investment — at least $10 billion — required to develop a launch vehicle of this scale.
Adjusted for inflation, US gov't spent the equivalent of $65 billion/yr in the 1960's to get a man to the moon:
Musk said 5% of SpaceX is working on the project and that number will increase over time. That's already 250 of the smartest engineers in the world working full-time on the Mars project. They've already test fired the Raptor engine for the rocket and produced a full scale tank of the fuselage for testing. These guys aren't going for 'exploration' like Zubrin wants, they're going for full scale colonization.
Every ship produced is a new member of the fleet that continually moves between both planets. Opening up an interplanetary transportation corridor. If you're someone with the spirit of a colonist, an explorer, an adventure seeker (there are many in the world with that attitude) then Mars is going to be the place you want to prove yourself on. It is romantic, risky, badass, and there are no shortage of people who are going to take the challenge.
An ever increasing number of ships leave every 2 years, and you always have the option to come back. I can easily see people doing fundraisers to go, universities offering scholarships, governments setting up stations to claim some land, companies sponsoring infrastructure projects to say they have a presence on Mars, etc..
"Musk said 5% of SpaceX is working on the project and that number will increase over time. That's already 250 of the smartest engineers in the world working full-time on the Mars project."
Correction: some of the smartest engineers in the US, maybe. But US laws don't allow SpaceX to hire anyone from outside the US.
It is actually possible to get ITAR exceptions for candidates who aren't US Persons. I know there are engineers at SpaceX from the UK, Canada, and I'm pretty sure Australia as well. It is a pretty long and expensive process from what I understand so it is used only for those with very specific skills or knowledge. I'm sure it would also be quite a bit harder or impossible for candidates from China/Russia or less "friendly" nations.
This of course isn't to imply that SpaceX has a monopoly on talented engineers, I'm sure they exist all over the world.
If humanity somehow managed to build a self-sustaining long-term colony on Mars, it'd be fascinating to watch how the martian humans would evolve over the next million years.
Probably no more fascinating than what we've seen of human evolution on Earth already. If you were living that far in the future, the differences between Earth people and Mars people would be mundane common sense to you already, just as we're not fascinated by how different chimpanzees are to humans.
One serious danger I haven't heard anyone mention mention in regards to the Mars colonization project (though it was considered to some extent in Arthur C Clarke's "Contact" and probably some other science fiction) is the possibility of terrorism against either the fragile spacecraft or colony.
Musk has said there will be no screening of the Mars colonists, and that anyone could go. That means someone who's mentally unstable and/or wants to make a name for himself (ala Herostratus[1] or any number of modern publicity-seeking terrorists and murderers) could go and attempt to harm the spacecraft or colony, both of which would be incredibly vulnerable to such intentional attempts at destruction and are guaranteed to get massive publicity were they to be destroyed or even merely attacked.
This could become even more likely if living on Mars long-term actually becomes viable, and people wind up spending decades on there. Some people will likely go stir-crazy and attempt to harm themselves and/or others.
People who are allowed to go live in Antarctica or out in to space are currently screened very carefully to be compatible with each other and able to psychologically withstand the rigors of life there, and the relative isolation. But there will be no such screening for the Mars colonists, according to Musk, and the isolation and danger on Mars will be even worse than it is in Antarctica.
The isolation and danger will be hugely stressful and difficult to deal with over the decades people will live on Mars. I've read that even in Antarctica, people are rotated out within a year or so because of the psychological difficulties of living there, and no one's been in space for much more than a year.
I'm glad Zubrin brings up the economics of Mars colonization, since that's easy to neglect. Once you're there, how do you make money?
Mining might be lucrative if Mars has gold or platinum or some valuable mineral that's easy to extract and worth more than its shipping cost back to Earth.
I'm skeptical that patents are going to be a major export. Inhabitants of Mars presumably will have better uses of their time than filing patents, and they would be competing against Earth-bound innovators against whom they don't have any particular advantage other than necessity. (Ideally, Mars wouldn't itself even be subject to patent law.)
Space Tourism will be a thing unless there's some explicit policy to prevent wealthy thrill-seekers from going to Mars if they don't plan on doing any actual work while they're there.
Science and exploration might be valuable professions. Like, if people on Earth put bids on locations, saying "I'll give you a thousand dollars if you drive your rover out to this location and take a few pictures and pick up some rock samples". Mining companies might be especially interested, but so would Earth-bound scientists who just want to know more about Mars.
Real-estate speculation might be another cottage industry. Developers are going to want to establish homesteads in valuable locations, and then they can sell adjacent lots to newcomers. (This assumes some kind of sane framework for land ownership. Hopefully such a thing will strike a sensible balance between being able to claim "dibs" on entire landscapes vs not having property rights at all.) As long as the population of Mars is growing, this could be a lucrative profession.
It's interesting to see that water on Mars has 6x the deuterium concentration of water on Earth.
It's unlikely to be a worthwhile export though. One in 2500 hydrogen atoms in Earth's oceans is deuterium. There's enough in your morning shower to provide all your energy needs for a year, and enough overall to run civilization until the sun goes out.
Isolating the deuterium takes some effort, but it's not terrible, and certainly easier than transporting it from Mars, even if isolating it on Mars were free.
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[ 3.2 ms ] story [ 172 ms ] threadPeople already stay on the ISS two to four times as long as Musk's proposed travel time to Mars, and they'll be landing somewhere with a third of Earth's gravity. They might all need to hang out for a day or two to get their Mars legs, but I don't see an issue here either.
Micrometeorite impacts haven't done the ISS any appreciable damage in its nearly 20 year service history. Again, doesn't seem like a problem.
People can definitely survive living almost entirely indoors. I expect VR will be big on Mars. But I think the lack of natural light will really limit the comfort level.
If someone can invent an invisible electromagnetic radiation shield that would change the game.
http://www.sr2s.eu/project-news/19-eu-space-project-will-all...
If we can find some nice lava tubes that can be sealed and pressurized, it might make for some rather spacious dwellings. But yes, I expect the first Martians to effectively be mole people.
I imagine living on Mars would be a lot like living in a place like Whittier Alaska [1] (a town where everyone lives in the same building). Not for everyone, but some people might like it.
[1] http://www.npr.org/2015/01/18/378162264/welcome-to-whittier-...
A penny-sized hole would give time to patch, and suits would likely be designed to compartmentalize in a leak. In a true worst-case scenario, chimp studies in the 1970s showed they could survive several minutes of total vacuum.
https://www.scientificamerican.com/article/survival-in-space...
These year long stays were on the space station, which has similar or less shielding. The Earth's magnetic field helps, but really, by the time you get to your Mars habitat with unlimited shielding mass available, your total dose is not that high.
http://www.theverge.com/2016/3/1/11138102/scott-kelly-year-i...
I guess they aren't well characterized yet.
Early travelers will face very significant risks. Radiation and zero g are indeed risks, but a minor compared to the other risks.
If you have a 5% of dying in transit or at Mars due to equipment failure, as well as a 2% increased chance of getting cancer at some time in the future, the first obviously is the one to worry about.
Have there ever been any serious plans or proposals to do that?
You really want a pretty large diameter so that you don't have a huge gravity gradient causing your astronauts discomfort. Tethers might be more practical than the classical doughnut designs for the near future.
https://news.ycombinator.com/item?id=12766618
I'm thinking (no spoilers) specifically of how Ceres, having been spun up to provide artificial gravity, becomes a destination for expecting mothers trying to avoid complications associated with low-G.
I'd guess that if the objectives and constraints used in the design process were revealed, it would all make complete sense. Elon has a track record of making technical and business decisions that turn out to be 100% correct in retrospect. The epic size of the vehicles are a feature, not a bug, for instance.
Musk has been surprisingly silent (or has seriously downplayed) on the radiation question, which is a pretty big deal for travel beyond earth's magnetosphere.
But here's the thing, IMO: Musk is offering ITS as a transport facility, nothing more, nothing less. If you have payload (a living human) that is fragile (sensitive to radiation) you bring your own extra styrofoam (you include weight of shielding water or lead or what have you as part of the payload).
But if he says that out loud, it'll hurt the momentum of the movement.
So there you have it.
Early trips would of course not have a large crew, since they'd be mostly focused on setting up a base, and be more about cargo and equipment. Saying "several tens of millions" is because that's generally what it costs right now to get someone to low Earth orbit. If we can get early trips to Mars down to what it would cost for a current orbital mission, that would be very impressive.
Start with ~$30 million (based on "several tens of millions") to get a person to orbit using current tech. Current tech doesn't use reusable rockets, and the cost of building a rocket greatly exceeds the cost of the fuel for the launch, so we'll assume fuel costs are 0. If you make a rocket that you can reuse for 10 launches, your price tag is down to $3 million to get a person to orbit. The next step is to make a bigger rocket: currently the Soyuz rocket is the only rocket taking people to the ISS (assuming this is roughly what you mean by getting someone to low Earth orbit), and it can only take 3 people at a time[0]. If you make your reusable rocket big enough to take 100 people at a time, your price tag goes down ~33x to $100k to get a person to orbit. Of course, a bigger rocket will probably cost more to make than current "small" rockets -- but a big reusable rocket would have to cost 330x more to build than a modern small rocket for future seats to cost ~$30 million per ticket.
So even the first trip to Mars should be well under $1 million per person as long as they make the rockets big and reusable.
[0] http://www.nasa.gov/audience/forstudents/k-4/stories/nasa-kn...
Even if the cost for the first few trips was $50 million per person, there'd be no shortage at all of people who would be paid for by governments or organizations with that kind of money. Might as well use it, and apply these funds to expanding the program.
Full reusability is really the essential part of this system - you can't afford to throw away any stage of a rocket this big. Fortunately, the larger the vehicle, the easier reusability tends to be (up to a point of course).
The implication is that you'll probably want to design an entirely new rocket if you want to make one that's significantly bigger than what you've made in the past, because rocket designs aren't going to be fully reusable at significantly different scales.
That's where the economic perspective comes in: rockets are expensive, and the bigger they are, the more expensive they'll be, from a raw materials perspective at a bare minimum. The hundred person rocket that Musk has proposed would already be significantly larger than any actually constructed rocket to date, so it has to be a new design, which means they're going to have to build and test prototypes. And some of the prototypes will probably blow up during testing -- hopefully not many, or they'll run out of money and won't be able to keep going.
Now if you want to build a rocket that can hold a million people, you'd probably be talking about the largest man-made structure ever. The only structure on this scale that I'm aware of (which was never built) is the X-Seed 4000, which would have housed 500,000 to 1,000,000.[1] Its proposed height was 4000 meters, which is about 33 times taller than the proposed SpaceX interplanetary rocket. If you scaled up the SpaceX rocket design to that height, the mass would increase 36000x, and the breaking strength would only increase 1000x. I think we would probably need some major advances in materials science to be able to make a rocket that big that didn't just disintegrate on launch.
Secondly, what about the economics of a million person rocket? The X-Seed 4000 would have cost roughly a trillion dollars (in 2016 USD) to construct, and it just has to sit on the ground. I'm going to assume that at the barest, most insane minimum, it would cost at least 10x as much to build a rocket that size. So that's 1/7 to 1/10 of global GDP (in 2014)[2] -- for one rocket -- that will probably disintegrate.
But! Let's assume that we make major materials science advances and can actually make it work, and we make it reusable up to 10 launches, and somehow we get the whole planet to agree to build this thing. The price tag actually isn't so great... $10 trillion / 10 million people = a million dollar price tag per ticket. So maybe my estimate is too high and we could build a rocket that big for a trillion, no more than building a building that big. Even then you're still looking at $100k per ticket.
So, in short... My guess is that there might be some technological and economic sweet spots that are a bit bigger than than the SpaceX design, but I think it's a good starting place in terms of feasibility. And yes, in practice there are some limits to how big you'll make your rocket.
PS. I don't think "breaking strength" is likely the most relevant factor for rockets (I an not a rocket scientist), but it's the principle of the scaling thing that matters. Plus a rocket has to have supporting structures to help it keep its shape, so breaking strength might be relevant after all.
[0] mden ↗ If I remember correctly from the presentation, Must claimed radiation was not a significant concern with the exception of things like solar flares. Can anyone comment on the accuracy of that? snrplfth ↗ Well, it's not nice out there, but hardly crippling. Cosmic radiation on the ISS is about 150 milliSieverts a year. Interplanetary space could get up to about 800 mSv a year. Not good, but if you can get there in, say, three months, then you've cut your exposure down to what an ISS crewmember would get in a year. The actual danger is solar flares, and for that you'll need some kind of shielding compartment onboard. The ISS is reasonably well-protected from those, but they'll really roast you if you're caught in interplanetary space. djokkataja ↗ I think Musk mentioned it somewhere in the presentation, but the initial plan for shielding if you're aware that there's going to be a solar flare is to angle the spaceship so that the engines are between the Sun and the crew compartment, and then have everyone packed near the water tank... or something along those lines (it might have been in response to a question in the Q&A time afterwards; I don't remember). snrplfth ↗ Yes, I expect that more advanced active shielding will eventually be developed - particularly since you can detect solar flare events before the radiation arrives. SolarNet ↗ I mean authors have been using that idea for years. The Red Mars trilogy for example (which was an at the time scientifically accurate example of mars colonization). wott ↗ Each of the stuff for which we read here people jumping and yelling "visionary!" "revolutionary!" "unforeseen breakthrough!" "brand new plan!" "disruptive improvement!", has been dealt with dozen of times in hundreds of SF novels in the last 80 years, which explored all the possible problems (problems are a more exciting matter for a novel than everything-goes-fine-and-as-planned). moogly ↗ You need radiation shielding on Mars as well.
Unless you live underground, I suppose. elihu ↗ Perhaps that's one of the advantages of using a really big ship; you can put more shielding / water tanks between the sun and the passengers.
I don't know that they'll have this on the first trips there, but I'd guess that magnetic shields might eventually be a standard component:
http://space.stackexchange.com/questions/3772/how-much-power...
The challenge with flares is that the radiation can come in from multiple directions, so a cylindrical water container that people can pack into is probably a better defense than just the bulk of the engines.
But since for most of those people, SF and anticipation is limited to Star-Wars + a couple of other movies/series and super-hero block-busters, they are not aware, and all these stuff appear as genuinely unprecedented technical and sociological thought breakthrough.
If it's a major problem, they might just orient the ship in a direction that gives the best radiation protection to the passengers and just leave it like that for most of the trip.
http://www.bloomberg.com/news/articles/2016-10-17/why-elon-m...
>Following the example of colonial America, let’s pick as the affordability criterion the property liquidation of a middle-class household, or seven years’ pay for a working man (say about $300,000 in today’s equivalent terms), a criterion with which Musk roughly concurs. Most middle-class householders would prefer to get to Mars in six months at the cost equivalent to one house instead of getting to Mars in four months at a cost equivalent to three houses.
Colonization of America was extractive. You send colonists and they survive on their own and even pay taxes and you get products back. That's not what would happen on Mars. There is nothing so valuable that it would be worth carrying back to Earth. At the same time it would take huge amount of money to support high-tech colony in Mars until it can support itself.
I imagine that the cost of moving people would be insignificant compared to the "colonization kit" that would enable the colony to become self sufficient. Developing that kit would probably cost more than all technology needed to move people to Mars. Just imagine the amount of technology transfer needed to build and maintain maintain systems for breathable air (air tanks, seals, valves, inspection equipment, instrumentation, automation electronics) without help from the Earth. Until Mars settlers can build things in-house, they need constant economic support from the earth.
ps. We don't even know how to sustain biosphere in closed environment yet.
That said, I am also doubtful. I don't foresee a trade-hub attracting 1 million people - if there are really a million people who want to go. Who the hell wants to risk their life and net worth just for the privilege of living on a rock less hospitable than Antarctica?
In other words, I believe that Mars' appeal is a mirage. Musk and company are seeing it as another Earth where people can live like here, with a little terraforming.
I think it would be much more difficult. Of course I could be wrong, or I could be right but, even then, Musk could be modern Columbus.
- Water and free carbon dioxide are hugely more abundant on Mars than on the Moon. These are essential supplies for increasing biomass and making fuel.
- There's a nice, somewhat-protective atmosphere.
- There's a 24.66 hour day.
- Temperatures are relatively moderate.
[1] - http://www.nbcnews.com/id/6908408/ns/technology_and_science-...
If you can get net energy by fusing He3, you can also do it by fusing deuterium, which is easier. And the end product of deuterium fusion is He3! (Half the time directly, the other half producing tritium which decays to He3.) So instead of sifting through millions of tons of dirt on the moon, you can just make He3 on Earth and gain energy in the process.
Deuterium fusion produces neutrons but they're lower energy than D-T neutrons. Fusion startup Helion (funded in part by YCombinator) is working on a hybrid D-D/D-He3 fusion reactor, and says only 6% of the output energy would be as neutron radiation.
Launches, yes, but landings? Athmosphere is your enemy during launches, but your friend in landing.
Mars has an atmospheric pressure less than one percent of that of earth. That makes losing speed other than with rockets a problem, and that requires bringing lots of fuel.
In addition, the athmosphere that's there can be windy and turbulent. That can directly affect a spacecraft, but also causes dust storms that can make it hard to measure distance to ground.
That's pretty much the whole of the economics. People and governments will jump at the chance to send humans to Mars, if there's a way to do it at a reasonable price.
The cost of the things that are necessary on Mars that will have to be shipped from Earth will be rolled into the ticket price. Hence the first few rounds of tickets will probably be quite expensive.
To make the colony self supporting, you need to transfer factories, chemical plants, machine industry, mining industry, etc.
Like they said, most of the cost is transportation. Which gets cheaper.
The really cool thing about this is that methane can be used as a feedstock to produce many plastics and the oxygen can be used for humans to breathe.
The MCT is a prototype for a seed factory style Von Neumann probe.
[1] https://en.wikibooks.org/wiki/Seed_Factories
Everyone's keeping quiet about the inevitable role of RTGs or fission reactors in early human Mars exploration.
Solar will come either via an abundance of payloads delivered to Mars as things ramp up, or via panels produced on Mars itself.
Other viable methods for power generation that are amenable to in-situ production include geothermal heat loops and solar concentrators.
How exactly do you know that? The only experiment about creating closed human colonies was deemed complete failures and not to be replicated due to ethical concerns.
We've never done this on any significant scale with success.
[1]https://en.wikipedia.org/wiki/Biosphere_2
Think of it more like a nuclear submarine with a greenhouse full of potatoes attached -- we can most likely do that.
Nobody's going to try to launch an entire mangrove forest on the first go. Biosphere2 is a failure of experimental design, not a failed experiment.
Maybe, but if we want to make Mars economically self sustaining the correct analogy is nuclear submarine that never surfaces and can totally self repair, including building new nuclear reactors and eventually replace all parts in itself.
There was Biosphere 2 experiment few decades ago, but they could not keep the biosphere stable.
There's just a huge psychological difference between knowing that you're in space, millions of miles from Earth or any kind of help and knowing you're in a simulation on Earth.
I suppose it's possible to fool people that they're in the former while actually being in the latter. But the ethical issues surrounding such an experiment would make it out of bounds for NASA. It might make for a fun scifi story, though.
And a base on Mars will not be a closed system. It will continuously draw in raw materials from the surrounding environment. Mars is enticing for this because carbon dioxide and water are abundant, giving you the three most important elements for fuel and food production.
The goal of Mars colonization is to create a second (eventually) independent base, so humanity has a chance in case of a catastrophic event.
I'd say even if it costs a trillion dollars, it's worth it. US GDP is what, 18 trillion per year?
It is when a private company is doing it.
How could they even begin to try to rebuild civilization when they can't even go outside without an apparatus that took thousands of years of science to produce? What is the speed divisor for advancement of a society marooned on a world it didn't evolve to live on?
I'm all for Mars colonization, but as a backup plan for Homo sapiens, it kind of sucks.
https://www.goodreads.com/book/show/22816087-seveneves
If humanity is wiped out on Earth, people in Mars are fucked anyway: they will be one depressurization accident from extinction.
Isn't that what that documentary Biodome was all about?
>Until Mars settlers can build things in-house, they need constant economic support from the earth
This is where digital manufacturing (CNC, laser cutting, 3D printing) actually makes sense. You go with the base materials and blueprints, and you can survive without transferring goods. You manufacture on-demand, and the blueprints can change based on feedback/results. Mars SHOULD have a prototype culture, the same as with explorers. With engineering/research help from earth, a fab lab on mars would be incredibly valuable. Science the shit out of it!
(And probably the transportation cost will be still high enough to make it mot profitable.)
Nobody is talking about using Mars as a manufacturing base to transport to Earth, it's all about creating a self-sustaining colony. There has to be stronger incentives for people/companies to move there. Even on earth there are many economic zones incentivized by lack of regulation etc.
The economy is just not going to work.
The parent comment isnt saying there will be an economy of building things on Mars and sending them to Earth, they're saying Mars can sustain itself without sharing an economy with Earth. Which I believe is true.
And for what it's worth, I'm actively working to build better robots with commodity 3D printers[1] and I hope to build self sustaining communities on Earth with 3D printed micro factories that produce all the goods humans need for survival.
I believe it is possible to make economically closed self sustaining communities. Both on Mars and on Earth. We've done it on Earth for a long time.
[1] https://github.com/tlalexander/Flutter-Scout
Self-sustaining community that can economically fund itself is out of reach even here on Earth. And, frankly, 3D printing isn't magic: it won't help that much. Can you 3D-print a glass window that can withstand 1 atm and has anti-UV coating?
I'm talking 10-20 years out for having a self sustaining community that manufactures its own hard goods. But I believe it is possible and I'm working on making it real.
I'm not relying on magic.
My (very uninformed) guess is that you could probably build a self-sustaining community using 3D printing, on the Alps or the Appalachian. (After all, our ancestors managed with stone tools.) Doing that on the South Pole will be challenging. Mars, forget it.
If you are persistent enough you could probably 3D print everything, I guess. Maybe you could 3D-print concrete and ceramic blocks to build a furnace that will be used to produce steel which will be shaped into a pipe (by another 3D printed machine) to transport hot gas to melt silicon oxide and produce glass.
However, after a few iterations, I guess people will ask "Why don't we just pour concrete over here in conventional way? That's much easier and cheaper."
I do think, however, that robotics and additive manufacturing will be critical to building significant parts of the machinery and buildings on Mars.
Certainly, sometimes you will use traditional manufacturing methods to construct things. But additive manufacturing has different capabilities and it will be used for different things. And unlike some people who claim additive manufacturing can't be used for anything, I believe that a mixture of traditional manufacturing methods and additive methods will be critical to building a colony on Mars.
Imagine for instance that you want to build some buildings. Lets say both pouring concrete and additive manufacturing methods would work. You need to build 40 habitats. Would you rather work all day in a space suit in the hazardous near vacuum of Mars to build the forms needed to pour concrete for the structures? Or sit in your pajamas in a habitat on a computer designing and controlling the robots that will do it for you? And in that case, maybe you will want to have the robots make forms and pour the concrete for you, but perhaps you will use additive manufacturing methods.
I can imagine the latter is easier for robots, and using robots is easier for humans than doing the labor themselves.
Of course, to build a robot that will manufacture a home out of concrete, you need to build the mechanical parts of that robot. How will you do that? Probably not with CNC machines and blocks of aluminum (making such parts was my job for 7 years BTW). Instead I imagine that you will keep a library of feedstocks for 3D printing and you will print out the robot parts in your lab.
Interesting fact: there are now some extremely high performance plastics available for common home-style 3D printers, including carbon fiber filled PEEK. At $850 per kg that's a material I don't think you'd use unless you had to, but if I were building a colony on Mars at $500k a head I think I'd bring 100kg of that stuff.
100kg of carbon fiber filled PEEK plastic will make a lot of concrete extruding habitat constructing robot frames.
You'll have to bring the motors and electronics separately. At least until you build that foundry....
See what I mean when I say 3D printing can help make a self sustaining economy possible?
If the real extraction happens on asteroids, then Mars or even the moon are a better base of operations just due to the smaller gravity well. And Mars isn't without its own mineral wealth. Several that would be important for growing food.
If you look at the delta-v map of solar system, everything massive like planets, is not going to be hub or center of extraction of minerals for other places. Mars would sit at the bottom of gravity well and be economical sink.
Deep space mining (robotic or semi automatic) of asteroids can be economically viable, but just few relatively small asteroids would provide Earth or Mars for centuries.
But raw materials are not enough, you would need industry to build all stuff you need and maintain it. If you can't manufacture 3D printer or CNC milling machine by yourself, you need to buy it from Earth. Just being able to make cast iron is not enough, you need high-tech equipment and manufacturing for them to survive.
Making Mars self sustaining circular economy would be massive systems engineering challenge.
Adjusted for inflation, US gov't spent the equivalent of $65 billion/yr in the 1960's to get a man to the moon:
http://www.popsci.com/real-cost-nasa-missions
Obviously, that'd be backup to backup plan for funding.
Every ship produced is a new member of the fleet that continually moves between both planets. Opening up an interplanetary transportation corridor. If you're someone with the spirit of a colonist, an explorer, an adventure seeker (there are many in the world with that attitude) then Mars is going to be the place you want to prove yourself on. It is romantic, risky, badass, and there are no shortage of people who are going to take the challenge.
An ever increasing number of ships leave every 2 years, and you always have the option to come back. I can easily see people doing fundraisers to go, universities offering scholarships, governments setting up stations to claim some land, companies sponsoring infrastructure projects to say they have a presence on Mars, etc..
Correction: some of the smartest engineers in the US, maybe. But US laws don't allow SpaceX to hire anyone from outside the US.
This of course isn't to imply that SpaceX has a monopoly on talented engineers, I'm sure they exist all over the world.
Musk has said there will be no screening of the Mars colonists, and that anyone could go. That means someone who's mentally unstable and/or wants to make a name for himself (ala Herostratus[1] or any number of modern publicity-seeking terrorists and murderers) could go and attempt to harm the spacecraft or colony, both of which would be incredibly vulnerable to such intentional attempts at destruction and are guaranteed to get massive publicity were they to be destroyed or even merely attacked.
This could become even more likely if living on Mars long-term actually becomes viable, and people wind up spending decades on there. Some people will likely go stir-crazy and attempt to harm themselves and/or others.
People who are allowed to go live in Antarctica or out in to space are currently screened very carefully to be compatible with each other and able to psychologically withstand the rigors of life there, and the relative isolation. But there will be no such screening for the Mars colonists, according to Musk, and the isolation and danger on Mars will be even worse than it is in Antarctica.
The isolation and danger will be hugely stressful and difficult to deal with over the decades people will live on Mars. I've read that even in Antarctica, people are rotated out within a year or so because of the psychological difficulties of living there, and no one's been in space for much more than a year.
[1] - https://en.wikipedia.org/wiki/Herostratus
Mining might be lucrative if Mars has gold or platinum or some valuable mineral that's easy to extract and worth more than its shipping cost back to Earth.
I'm skeptical that patents are going to be a major export. Inhabitants of Mars presumably will have better uses of their time than filing patents, and they would be competing against Earth-bound innovators against whom they don't have any particular advantage other than necessity. (Ideally, Mars wouldn't itself even be subject to patent law.)
Space Tourism will be a thing unless there's some explicit policy to prevent wealthy thrill-seekers from going to Mars if they don't plan on doing any actual work while they're there.
Science and exploration might be valuable professions. Like, if people on Earth put bids on locations, saying "I'll give you a thousand dollars if you drive your rover out to this location and take a few pictures and pick up some rock samples". Mining companies might be especially interested, but so would Earth-bound scientists who just want to know more about Mars.
Real-estate speculation might be another cottage industry. Developers are going to want to establish homesteads in valuable locations, and then they can sell adjacent lots to newcomers. (This assumes some kind of sane framework for land ownership. Hopefully such a thing will strike a sensible balance between being able to claim "dibs" on entire landscapes vs not having property rights at all.) As long as the population of Mars is growing, this could be a lucrative profession.
It's unlikely to be a worthwhile export though. One in 2500 hydrogen atoms in Earth's oceans is deuterium. There's enough in your morning shower to provide all your energy needs for a year, and enough overall to run civilization until the sun goes out.
Isolating the deuterium takes some effort, but it's not terrible, and certainly easier than transporting it from Mars, even if isolating it on Mars were free.