Saturday, November 9, 2013


Here and here.
The goal of keeping people alive in an enclosed, self-contained environment whisking through space may be beyond human capabilities for many centuries.
I believe this is a very true statement although predicting anything centuries out is a bit dicey.

But note this really has nothing to do with putting a colony on mars. We can certainly get people to mars orbit. SpaceX is even confident enough to put numbers to landing. $150m to $195m to put a lander in mars orbit. This lander will put 2500kg on the surface including four passengers.

There is no question we are up to the challenge of getting people to the martian surface. Can they live there?

A self contained environment works for perhaps a long time but will ultimately fail. Recycling is not going to be 100% so you need to provide for the losses. More important is that it is not growth. People don't want to live forever in tuna cans. You've got to go into the harsh environment to get resources. The biggest resource being more living space. Your sealed environment is going to be contaminated. So it's not really a sealed environment you need but an environment you can clean.

Which is funny since people now claim we can't do it because of dust. They talk of it as if they've forgotten that going around the earth at some places and times can kill the unprepared just as well.

Air filtration is a known technology. We can handle it. We just need to prepare for it. It is not a show stopper except in the minds of those that aren't going to be a part of this next age of humankind. Well a few will later claim they knew it all along.

Update from CJ: [To build tractors on mars] they will need to have either 3-printing, or it's going to be a very long time until they can do this.

Not you too CJ? Why does 3D printing cause us to forget how we do things without 3D Printing? To make a tractor you need the parts and the labor of two people for about 8 hrs. (in the example I'm using.) Enough parts to build two tractors can fit on one lander (2500kg.)

To build the parts you need material and a machinist. Of the 1000 or so parts required, hundreds of them can be made in seconds (3/4" washer x 238) by a skilled machinist. All of them could be produced in a month or so. The raw materials are everywhere in martian dirt (15% iron which is easily made into steel using the carbon in the martian atmosphere.)

It's not just the initial tractor parts we should send. Along with the machinists personal tools we should send parts for the tools like metal extruders. They can make the dies themselves. This quickly gives them a leg up on industrial capabilities. Otherwise they'd have to start as blacksmiths but that works as well until they move beyond that.

That's not to say that 3D printing isn't useful, but it is not required; they will have it anyway.

Something else I'd like to add... some things are not visible to many people. In any city you will find machine shops because they are essential as a foundation for everything else. Alvin Toffler talked about transitions as if they were clearly delineated. They aren't. TV didn't eliminate radio. Radio didn't eliminate reading. ...and so on. We may live in a disposable society where everything is made on the other side of the world, but that's just circumstance, not the only way things can be. Mars will be different because the circumstances are different, but the underlying reality doesn't change.

Another something... what's the difference between big industry and garage industry? Scale. 3D printing is not the only way to get self replicating. The key ingredient is the design. Designs can be scaled, but you have to have one first. 3D printing is just another tool in the toolbox.


Anonymous said...

Build tractors on Mars?

For that, they will need to have either 3-printing, or it's going to be a very long time until they can do this.

The sheer number of parts, even for a simplified design, would be a nightmare.

We don't need mass production; that's a great system, but it takes a huge amount of infrastructure IMHO what we need are more akin to skilled blacksmiths of the 18th century, who could make any number of things.

My best guess; 3-d metal printing is becoming practical, and would be ideal on Mars. With that, plus plastic printing, you've got the diverse production capacity you need with very little upmass.

BTW, one of the biosphere issues was that they insisted on using all-natural methods, essentially creating a giant terrarium. A small amount of lithium hydroxide, for example, would have solved their CO2 issue. A bit of electrolysis would have solved their O2 issue.

Also, BiosphereII had heat issues. (that's what you get when you build a glass house in a hot desert). In a cooler climate, things would have been easier.

A further issue; their airtightness was not as good as they wanted or claimed. I remember seeing ants from the rain forest biome on the outside of the structure in huge numbers. Somewhere underground, they were getting in and out with ease.

Arizona CJ

ken_anthony said...

Great info on Biosphere 2. Thank you a bunch. See update regarding tractor.

Anonymous said...

Great update.

I agree that building tractor from parts is easy (And with or without 3d printing, they'll have to be able to do that). But, shipping all those parts from Earth would be a lot of upmass. For the first few, not a problem, but I don't think that's viable long term. So, they'd need to go ISRU for parts (for both new tractors and repair parts on older ones)

But... you mention skilled machinists making parts in seconds. Sorry, but I think you're way off on the timescale. Okay, try this (It caused me a rude awakening once); go to a machinist and ask if he can make you a new cylinder head, or for a Mars tractor, I'm thinking the electric motors, suspension, steering, etc Sure, he can make leaf springs for the suspension, but he can't make the shock absorbers. So, do without those, but what about the motors?

Designing the tractor to be easy to build would obviate most of the issues, but far from all. Forging isn't easy (ever watched it being done?) and even making steel requires a smelter and factory (plus a lot of O2). Also, ask a machinist if he can make a plain old nut and bolt that's interchangeable with others; yes, he can, if he has the right equipment, but it's going to take a huge amount of time and work, every time, and the machinery to do it en mass would fill several landers.

For another example, try asking a machinist to make a car transmission. He won't be able to. Same with a new engine, or even a master brake cylinder (as many a classic car buss has learned to their dismay). You can do a lot in a machine shop, but that's cutting, not casting, and some shapes just can't be made via cutting alone.

For small, simple parts like nuts, bolts, joints, sockets, etc, 3d printing would IMHO be far easier. (for washers, stamping is easier, but only if you need a lot)

Or what about small plastic parts, such as the cooling fan (just the blades) for a computer, or a space suit? Think about the infrastructure needed to make a new one; it's a lot. Or, you have to take along huge parts inventories. Far easier to print what you need.

I don't see 3d printing as a show stopper (You can do it without it) but I think viable 3d printing could make the bootstrapping process far, far easier, as well as being far easier on the upmass side.

There are other showstoppers for Mars colonization, but even I don't think lack of 3d is one of them. I just think it would make it a lot easier, especially in a colony's early days, and especially if its on a tight upmass budget.

Now, what very well be a true showstopper regarding Mars colonization is an issue I've yet to see addressed; proper food preparation. Specifically, how do you design a smoking grill for Mars? You need hardwood or mesquite wood for it, and growing it would take years, and there's the smoke to consider, etc. After all, without real BBq ribs, human life cannot exist. :-)

Secondly, coffee; good coffee hasn't been successfully grown in greenhouses here on earth, so have we even researched how this can be done on Mars? This should be a primary research goal, placed well ahead of other, less critical colony necessities such as air and water.

Arizona CJ

ken_anthony said...

Such a great comment it deserves it's own post.