Why colonize Mars and not the Moon?

[Drakkith]

I maintain the position that seriously considering a self-sustaining colony ANYWHERE where only partial earth-gravity is available at this point is pure folly. I don't discount the possibility in the far future but seriously attempting it at this point is irresponsible and unethical.

No one is seriously considering a self-sustaining colony in the near future (no one who knows what they're talking about at least). It isn't remotely possible at this time and won't be in the near future.

 

[nikkkom]

I seriously doubt that is true. The things you describe to be done on Mars are really, really hard and in some cases we don't really even know how we would do them, which makes them little more than wild guesses. Can you tell me how much it will cost to manufacture a million cubic feet (at STP) of oxygen on Mars...

You miss the point. It's not about cost. It's about possibility. Producing CO (which is fuel), nitrogen and noble gases on Mars is possible - you don't even need to mine anything, just process gases! - and involves known industrial processes.
On the Moon, it is exceedingly difficult.

 

[sophiecentaur]

You seem to underestimate the education of astronauts massively.

Education and indoctrination are different matters. The latter tends to win in most cases. If the facts are presented in the appropriate way, people often don't make the best choices. Think of the thousands of bright, well informed intellectuals who haves self destroying drug habits. Society needs to look after everybody and that's why we have ethics committees. One day, an ethics committee could save anyone of us from a grisly fate.

 

[sophiecentaur]

You miss the point. It's not about cost. It's about possibility.

Nothing in life is "not about cost". Costs may change over long periods of time but they still count.

 

[nikkkom]

Nothing in life is "not about cost". Costs may change over long periods of time but they still count.

Ok, here are my predictions about cost of industrial N2 and noble gases on Mars, in a future well-established colony (say, tens of millions of people): same order magnitude as on Earth.

Whereas on the Moon, in a future well-established colony (say, tens of millions of people), they will be imported from Earth. Carbon, chlorine (and goods containing them) too.
Maybe even oxygen and hydrogen will be cheaper to import from Earth - locally produced ones can end up too expensive, no matter how hard you try to lower the cost.

 

[sophiecentaur]

Ok, here are my predictions about cost of industrial N2 and noble gases on Mars, in a future well-established colony (say, tens of millions of people): same order magnitude as on Earth.

Whereas on the Moon, in a future well-established colony (say, tens of millions of people), they will be imported from Earth. Carbon, chlorine (and goods containing them) too.
Maybe even oxygen and hydrogen will be cheaper to import from Earth - locally produced ones can end up too expensive, no matter how hard you try to lower the cost.

Millions of New Martians. What sort of timescale do you envisage here?

 

[nikkkom]

Have no idea. Depends on how much we "invest" into the project.

However, the future has this nasty habit of always happening. It's wrong to pretend it won't - "year 2000 bugs" are the example of such thinking.
If you definitely decided to establish a colony somewhere, in this decision you cannot ignore problems a future large colony in this location will face. If your colony succeeds (does not die out or get evacuated, but grows), then these problem will inevitably happen. Moon's dearth of volatiles is this type of problem.

 

[sophiecentaur]

It strikes me that, unless a colony is completely self sustaining, there is really no point in contemplating it. The arguments in favour of colonisation are all very arm waving and idealistic ("to Boldly Go" etc.) and not very well founded at all. (Funny, but I hear echoes of Brexit in what I just wrote.)

 

[mfb]

Stop misquoting me please. I said "see what happens" for the effects of low-g on the first astronauts on Mars, or potentially in an artificial low-g environment close to Earth. A scientific study on how the body of astronauts reacts to these conditions, in the same way the effects of zero-g are studied on the ISS now.
If anyone thinks this is unethical, then I don't see what kind of research would be ethical at all.

The logical next step after achieving substantially cheaper access to earth-orbit is to establish an infrastructure to harvest space-based resources because that will substantially increase what is possible and practical for you.

Not if access to space becomes cheap enough. Then sending up more stuff is cheaper-

Going off half-cocked to Mars with the ambition to establish a self-sustaining colony before you even have the necessary knowledge to make that work - or even know that it's possible given human physiology - is insane.

No one does that. All ideas for Mars colonies are always under the condition that research expeditions lead to promising results.

It strikes me that, unless a colony is completely self sustaining, there is really no point in contemplating it.

No country on Earth is completely self-sustaining. Not a single one.
And you are proposing a deadlock situation. A colony cannot start self-sustaining. It will take a while to become self-sustaining. Does that mean it is not worth starting the process because the colony is not immediately self-sustaining?

 

[sophiecentaur]

No country on Earth is completely self-sustaining. Not a single one.

That's very true but every Earth Colony (not counting non-colonies like Antarctica or temporary installations) has pretty much everything it needs to be self sustaining. The first colonies on Earth were completely self-sustaining or they died out. There are places on Earth where it's just not worth bothering to try and colonise - and we don't. There is water, sunlight and air, for a start. If the makings of 'air' and water are not available then it's a non starter. Likewise for many other raw materials. There will be instances where a different approach to a problem could reduce the need for some 'essentials' (the mother of invention etc.)
Moreover, no country on Earth takes more than a few hours of (cheap) transport to reach.
But everyone is being very slippery about the timescales involved here. Wait long enough and I guess we could solve any problem.I reckon it will all be a lot later, rather than sooner.

 

[mheslep]

Funny, but I hear echoes of Brexit in what I just wrote.)

Going back to a state of the past is fairly opposite of going where no one has ever been.

 

[mheslep]

unless a colony is completely self sustaining, there is really no point in contemplating

No, unless the colony can trade something of value for what it needs, there is little (long term) point. What country on Earth is "completely self sustaining", i.e. what country can flourish without some form of trade?

 

[mheslep]

No one does that

Eh, maybe with the exception of the Mars One people, who could be said be "half-cocked"

 

[stefan r]

Ok, here are my predictions about cost of industrial N2 and noble gases on Mars, in a future well-established colony (say, tens of millions of people): same order magnitude as on Earth.

Whereas on the Moon, in a future well-established colony (say, tens of millions of people), they will be imported from Earth. Carbon, chlorine (and goods containing them) too.
Maybe even oxygen and hydrogen will be cheaper to import from Earth - locally produced ones can end up too expensive, no matter how hard you try to lower the cost.

Nitrogen will be much more expensive on Mars. On Earth nitrogen is a by-product of oxygen production. All you are paying for is the cost of delivery (also purification and chemical analysis if you require that). On Mars the demand will be for nitrates and ammonia.
Argon will be much cheaper on mars. On Earth argon is extracted from oxygen production. It is an added distillation. Burning off oxygen wastes a valued product. On Mars Argon will be a by-product of nitrogen production. Furthermore, nitrogen could be converted to ammonia in the haber process without separating the argon.

If we have 10 million people on Mars or on the moon there will be outposts at Ceres, other asteroids, and moons of Jupiter or Neptune. Dropping ammonia from the outer solar system to Mars and the moon cost very similar amounts.

 

[rootone]

Nitrogen is the most common element in the atmosphere of Earth, it also exist in Mars' atmosphere in useful amounts.
It isn't a by-product of something else, Nitrogen is Nitrogen, unless talking about fusion reactions inside stars.

 

[stefan r]

Nitrogen is the most common element in the atmosphere of Earth, it also exist in Mars' atmosphere in useful amounts.
It isn't a by-product of something else, Nitrogen is Nitrogen, unless talking about fusion reactions inside stars.

There are many major companies selling products made from air. One of them is called "Air Products" and has annual revenues around $10 billion. One of their customers, NASA, bought oxygen from them for rocket launches. Oxygen is oxygen and is a product usually produced on Earth through liquefaction and distillation of air. Nitrogen is nitrogen and is a by-product of oxygen production on earth. Liquid nitrogen frequently gets used for cooling and for purge gas.
Water is also a major industry in the United States.

 

[sophiecentaur]

Going back to a state of the past is fairly opposite of going where no one has ever been.

No one has ever been to a state of 'not in Europe any more'; that's pretty radical. The consequences have not been thought out by many of the Brexiteers - most of them will probably have been hoping for a pre 1970s situation but that is unreal.

 

[mheslep]

Nitrogen will be much more expensive on Mars.

2.5% of Martian atmosphere.

 

[mheslep]

No one has ever been to a state of 'not in Europe any more'; that's pretty radical...

Radical? More like more of the same. How many countries split from the British empire which spanned the globe a century ago? I suppose King George III called the colonists radical. This time at least Juncker won't be able to send the Dragoons to attemt to hang the Brexit leaders.

 

[stefan r]

2.5% of Martian atmosphere.

wikipedia says 1.9%.
The cost of nitrogen production involves removal of either 97.5% of the components or 98.1% of the components. In either case it is much more expensive than Earth where you have reasonably high purity nitrogen left over from oxygen production. On Earth's economy nitrogen is free once you subtract the cost of refrigeration in the case of liquid N₂ or subtract cost of bottling in the case of pressurized gas.

 

[mheslep]

The process of N2 production would be that same on Mars as on Earth, refrigeration to liquefy out the desired gas. ThE difference would be in energy, so the cost difference depends on energy cost.

 

[nikkkom]

wikipedia says 1.9%.
The cost of nitrogen production involves removal of either 97.5% of the components or 98.1% of the components.

CO2 "removal" will actually be the crucial step in atmospheric processing on Mars: you need carbon for all kinds of organics (plastics and more) and oxygen for breathing, rocket oxidizer and many industrial uses.

In general, CO2, H2O, N2 and noble gases extracted from Martian "air" are all quite useful.

 

[sophiecentaur]

2.5% of Martian atmosphere.

When you consider that the atmosphere is at very low pressure, compared with Earth's atmosphere, that could be an added hurdle for the Haber Process (talking as a not-industrial chemist) if it's needed for agriculture etc. (But I guess that, eventually, within a biome, N₂ would end up at higher concentration for recycling)

 

[mheslep]

When you consider that the atmosphere is at very low pressure, compared with Earth's atmosphere, that could be an added hurdle for the Haber Process (talking as a not-industrial chemist) if it's needed for agriculture etc. (But I guess that, eventually, within a biome, N₂ would end up at higher concentration for recycling)

Im not a chemist either, but a change in pressure doesn't not necessarily effect Haber; it effects power needs, as compressing the Mars atmosphere 170X in the front end produces Earth like conditions for whatever chemical process may follow (not that this is necessarily the best approach).

 

[mheslep]

CO2, H2O, N2

Water is only trace in that cold atmosphere, and that only near the poles. Maybe mine the soils for ice and/or recycle for human needs. BYO H2 for fuel, use local C and O, is the Mars Direct plan.

 

[stefan r]

CO2 "removal" will actually be the crucial step in atmospheric processing on Mars: you need carbon for all kinds of organics (plastics and more) and oxygen for breathing, rocket oxidizer and many industrial uses.

In general, CO2, H2O, N2 and noble gases extracted from Martian "air" are all quite useful.

Aggregate is useful. By weight one of the most used materials in civilization. I recently bought aggregate in urban eastern Pennsylvania. I made a small section of sidewalk. There is a rock dealership in-between my house and my in-laws. They offered 50lb bags of crushed limestone for $6 each or 1/4 ton for $8. When they realized I was loading into a Honda Accord they decided not to weigh at all and told me to take as much as I could. I checked the shocks (distance between tires and wheel well) with my hand as I shoveled to avoid damage. No one involved acted like the material had value. Less labor and lower liability had value to them and my car had value to me.

If you get truckloads of "earth" delivered in the Northern USA you will likely find that topsoil is slightly more expensive than aggregate which is slightly more than subsoil. Sometimes crushed aggregate is a bit more if you specify grading. Some stone types can get expensive depending on your location (diamond extreme example). The price of "fill" is an anomaly. Cubic yards of fill delivered are likely to be a little more than half the cost of delivering your aggregates or top soil. Looking at the chemical composition and relative abundance on Earth will not explain the prices. The low cost of "fill" occurs because the company selling it is also selling a contract to remove it and they are avoiding a charge for dumping it.

If we look at a product on mars, say polypropylene grocery bag. You could say that the carbon came from our valuable carbon dioxide atmosphere. Or we could say that the difficulty purifying 96% CO₂ into 99.999 CO₂ is very easy compared to the energy cost of reducing the the carbon. So easy that the price can be ignored. The value of hydrogen on Mars will be so much higher than the cost of reducing CO₂ that we could almost disregard that too. By weight finished plastic goods may be cheaper than saturated hydrocarbons(diesel, natural gas etc) because the hydrogen content is lower.

On the moon you get odd ideas like using aluminum regolith instead of portland cement to make lunacrete. link. Portland cement concrete uses a lot of water.

 

[Wastrophysicist]

Why? To prove we can. There are literally hundreds of reasons why, but this one is worth enough to colonize whatever you want to.
I mean, for example, AI is just to prove that we can do it. We, human species, want to show ourselves that we can push the boundaries of what it was assumed to be the limit and feel like we're super smart. Why did we go to the Moon? Why do we deal with Astrophysics, the Big Bang, Quantum Theory and such stuff that probably won't be useful in our life (at least in the next 100 years)? Curiosity, sure, but the main is self-centeredness.

 

[mheslep]

Why do we deal with Astrophysics, the Big Bang, Quantum Theory and such stuff that probably won't be useful in our life (at least in the next 100 years)?

Those don't cost $30B a shot and the risk is entirely different. Space travel has very high likelihood of killing people, maybe everyone involved for a Mars mission.

 

[stefan r]

Why? To prove we can. There are literally hundreds of reasons why, but this one is worth enough to colonize whatever you want to.
I mean, for example, AI is just to prove that we can do it. We, human species, want to show ourselves that we can push the boundaries of what it was assumed to be the limit and feel like we're super smart. Why did we go to the Moon? Why do we deal with Astrophysics, the Big Bang, Quantum Theory and such stuff that probably won't be useful in our life (at least in the next 100 years)? Curiosity, sure, but the main is self-centeredness.

Why not colonize both the Moon and Mars? Why neglect Oberon and the Kuiper belt? Alpha Centari is only a few light years. Building a Dyson Sphere might prove something.

In high school I read a book called "the Tao of Pooh". I remember the saying "a thousand mile journey begins with one step". The debate is which step is the next one. There is more than one path available.

 

[mfb]

Space travel has very high likelihood of killing people, maybe everyone involved for a Mars mission.

The risk is tiny for everyone involved apart from the few astronauts that would go to Mars. Space missions are not just the astronauts.