Catalytic Enzymes and cleaning up Venus' atmosphere?

[rockett]

The ability to use materials found in space to build a enourmous 2 km habitat.

The first ones don't need to be that big. That number is just thrown out there as an extreme example.

Carbon nanotubes in a INSANE amount. Tons of material that can withstand constant bombardment by high winds (erosion of the surface of such a structure by wind driven particles)

Carbon nanotubes are not needed, believe it or not a simple structure like a Bigalow space hab would do if it were large enough. Or think of a structure like a zeppelin that you lived inside.

Dust particles are not a factor, as a floating habitat, if there were any (and there is no evidence there are at that altitude) you would be moving along with them. It's highly unlikely there are, surface wind is only about 1 mph which is what would have to lift them into the upper atmosphere. Not like Mars and it's dust storms (which are documented by the rovers).

and emersion in a acid enviroment.

The word is immersion. The sulfuric acid content was overestimated in early observations. http://hyperphysics.phy-astr.gsu.edu/HBASE/Solar/venusenv.html As a matter of fact, the sulpher content in the upper atmosphere has been dropping since 1978, leading some scientists to speculate that it was injected by a volcanic event, which seem to be rare on Venus.

Tons of electronic and highly sofisticated (sp: sophisticated) machines of all types

They would be brought along anywhere we colonised anyway.

Yes we have carbon nanotubes but in a stupidly tiny amount. The only other material that comes to mind is the entire structure made out of Lunar regolith turned into glass which if memory serves correctly could be made stronger than steel.

No need for such extremes, we have acid proof fiberglass in use today in chemical plants. We could probably develop still better materials if we wanted to.

But all of this hooks on one huge thing. How to get it all there. You cant use the venusian surface for material. Too much pressure to much gravity to get a it back without ANOTHER super advanced form of transportation.
So it would all have to get there from space.

One scheme for speeding up Venus rotation and increasing the magnetic field is using asteroids as moons. So, move them and mine them. Would be a good exercise in learning how if we ever needed to divert one from Earth anyway. We drop it on Venus and nobody cares.

Look i LOVE the idea but i dont see it as viable for another 100 to 150 yrs.

Maybe for the super sized 2 km colonies, but we could start with today's tech. Nothing new.

Mars however has everything we would need there. We are currently working on many things to cut radiation so thats out. The Atmosphere is not much of a problem depending on what you make it out of and the right construction and engineering technics (sp: techniques) thats no longer a problem.

Power could be handled by nuclear reactors or maybe in the future fusion. Meanwhile the lighter gravity means its alot easier to launch things to space.

Yes Mars has a lot, except:
1. Pressure
2. Magnetic field
3. Radiation shielding (you have to go out sometime, if for no other reason to prospect for those resources you keep talking about)
4. Temperate climate
5. Abundent solar energy
6. Gravity (true, bad for launching, but good for human health long term)

Look my point is that while Venus may be a better choice for colonization in the next century or more Mars could be done with present technology. And you could use the science behind terraforming mars for use on venus.

Venus can be done with current tech also.
You wouldn't have to live in a tunnel all your life, just to keep your genes intact.
The atmosphere you are living in could easily be processed into something you could breathe, and water. Given time, and a chance to work with it on the spot, we might even find a way to reduce the atmosphere faster. One possibility would be to bioengineer extremophiles from Earth (that live in volcanic vents, and eat sulpher) to float in the atmosphere.
We would eventually find ways to bring material up from the surface also.

In any event, the best numbers I've seen for terraforming Mars show a minimum of over 100 years (using the most extreme interventions) to 40,000 or 50,000 years. And even then, you would need breathing and pressure gear, radiation protection, and it wouldn't be appreciably warmer.

Sure, Venus might be tougher getting started, but in the really long term, big scheme of things, it may be a better choice for creating a real second earth.

 

[BenS1985]

I think one of the issues with the argument is that we simply haven't looked into Venus on a serious scale, because its deemed 'uninteresting' compared to other locales like Mars, Titan, or the moons of Jupiter. Unfortunately, that is a sad thing, as I (and others) believe that Venus has a lot of potential for the reasons I've listed.

However, that doesn't mean that the technology needed to begin colonization, research, or science missions are too far in the future, or difficult/costly to do.

As stated, the huge advantage with Venus is issue of native air floating. Now, as rockett said, I was only giving the more extreme examples of habitats - do you think that we will have cities on Mars that are 2km in diameter any earlier than the next 100 years? Much in the same way, your looking at the extreme example I was offering. Heck, coat the Goodyear Blimp with something to resist any sulfuric acids, and it'd float like no other in Venus' atmosphere! Add a bigger deck (since such a blimp would have much more lifting power), and you'd have a pretty cheap colony. No CNTs, no exotic materials. Just the costs of aerobreaking. The real hurdle would most likely be in developing a way to re-launch from a 0.88G world using native atmosphere and materials.

As for the uber-habitats - on a much smaller, more realistic scale, you could simply launch a Terran-like blimp in the jetstream to test possible technologies to see how well they would work in Venus' atmosphere for further missions. I would imagine that the costs to build and deploy a blimp would not be very expensive, sans the aerobreaking maneuver. Such a blimp would be quite inexpensive, and could help us learn to understand what is needed to prepare for future colonies. How much more expensive would such a project be than a Mars rover? The difference would be that such a blimp would be many multiples larger than a Mars rover, and could easily be livable with a few modifications.

Eventually, you could add more and more blimps and link them together. Such types of blimp colonies should be rather easy to build, join and use...I would doubt that the technology would be further than a decade or two away (or less if it ever became a priority).

As stated, there are pros and cons with both destinations for colonies. They both have some major pros and cons. However, I really believe that Venus is more colonizable due to the simple fact that its more Terran-like.

To me, the pros/cons are:

Venus
+ Thick, 1-bar atmosphere
+ Co2 based atmosphere
+ Temperate climate
+ Close to Earth
+ Closer to Asteroids (Landis has a great note on this)
+ Potentially 'better' gravity for human development
+ Most likely cheaper to develop very simple colonies
+ In case of habitat failure, has best chance of survival of any potential colony
+ Abundant solar energy
- Possible sulfuric acid in atmosphere that may complicate habitat development
- Difficult to obtain materials for colony expansion
- Gravity increases costs/demands for return launch missions
- Lack of water in atmosphere, requires importation of water

Mars
+ More interest by science to colonize, currently
+ Good materials for colony building
+ Abundance of water
+ Lower gravity yields easier return trips to earth
+/- Has atmosphere (albiet a very meager one)
+/- Colder, more variable climate (coupling with almost no atmosphere, may not be a problem unless your suit was compromised)
- Increased radiation risk
- Further from Earth
- In case of habitat failure, colonists would face little chance of survival
- Further from other colonization/exploration targets

Those are a few quick-hits on the advantages and disadvantages. Ultimately, I cannot give a proper cost analysis on what it'd take to colonize either places. However, since we would be importing 100% of materials to both places for seed colonies, I could only believe that Venus would be quite a bit cheaper due to less technical issues of simply placing a blimp in the clouds vs. constructing multiple habitats.

 

[EarthlingX]

Simplest answer to all this trouble, i can think off goes something like this :
- get to LEO,
- mine asteroids for resources, no need for lander, you can dock with manoeuvring propulsion,
- tele-operations, evolved in LEO - Geostationary orbit, Lx, and Lunar operations,
- go from the top, sky-hooks might be a thing to look into, they have lower point speed comparable to Venus winds, or some other, something interesting might come out. A lot could be done with the current technology, to many places we can get with an elevator.
Wiki : Skyhook structure

We need to know more about Venus, of course, before deciding for any plan, the best it would be, if all plans could run in the parallel, so we should start looking for similarities, instead of differences.

Looking for similarities will also show the best path to take.

 

[rockett]

- Possible sulfuric acid in atmosphere that may complicate habitat development
- Lack of water in atmosphere, requires importation of water

There actually would be a LOT of water in the atmosphere. If we reduce it to an earth-like mix, it is my understanding that 80% of Venus' surface would be covered by water (Earth is 70% covered).

One way we can get it out is processing the sulphuric acid. It works like this:
H2SO4(sulfuric acid) + 2NaOH(sodium hydroxide) = Na2SO4(sodium sulfide) + 2H2O(2 molocules water)

 

[rockett]

- go from the top, sky-hooks might be a thing to look into, they have lower point speed comparable to Venus winds, or some other, something interesting might come out. A lot could be done with the current technology, to many places we can get with an elevator.
Wiki : Skyhook structure

Great idea! It would actually have a lot of advantages, since you wouldn't have to go all the way to the surface

Looking for similarities will also show the best path to take.

I agree wholeheartedly

 

[neutrino78x]

With Mars, you can reach the surface, with all its indigenous resources, now, before terraforming. On Venus, until the terraforming effort has made a big difference, all the materials to build colonies and sustain them will have to come from somewhere else.

Both Mars and Venus have atmospheres made of carbon dioxide, which means you can derive oxygen to breathe from the indigenous atmosphere.

As far as radiation, I would argue that since it is closer to the sun, it would have more radiation. Maybe on the surface of Venus, you don't have any gamma rays, etc., however, you also can't operate on the surface with current technology.

--Brian

 

[rockett]

As far as radiation, I would argue that since it is closer to the sun, it would have more radiation. Maybe on the surface of Venus, you don't have any gamma rays, etc., however, you also can't operate on the surface with current technology.

This is one of the advantages of Venus, it has a magnetic field.

The economy for either mission really requires (as EarthlingX pointed out in an earlier post) mining asteroids:

mine asteroids for resources, no need for lander, you can dock with manoeuvring propulsion

In that, he is quite right. Comets offer still more resources, if we need something not available on one of the various types of asteroids. For the amount of energy expended, it is the most economical. Use lunar resources (the next most economical) for resources unobtainable on asteroids, such as water.

All this requires another step in technology, including processing and fabricating in space. But these techniques could be developed in LEO at the ISS, with samples returned to it by unmanned vehicles. This will be required anyway if we are ever planning on a sustained presence in space over the long term.

So what all this adds up to, is that the original Constellation mind set was correct. The most economical way to anywhere else lies in first lunar (all that water recently discovered, really is a game changer) and asteroids, then Venus or Mars. Being able to boost water into orbit at 1/6 G makes a HUGE difference from hauling it, or H2 and O2 up from Earth. Sending it up as water, makes a really nice storage medium, because you don't have to worry about cryogenics, split it in orbit with solar energy, and you have fuel.

 

[gravityTug]

I like the idea of a floating colony whilst the atmosphere is processed, although I'd want to be mighty sure the thing is stable before I stepped foot on it. No more danger than being in a spaceship I guess, just that the thought of plummeting through the Venusian atmosphere is horrible.

How about having a massive sun blind completely obscuring the sun from Venus, does anyone know how large such a blind would have to be and how fast this would freeze the atmosphere, if indeed it would? Possible benefits are that you get to cool Venus down quicker and you could process what needs to be processed easier in solid form (just guessing here)? I envision that once we have Venus the way we like we could then lower the opacity of the blind to say ~50%.

With the help of a few ice comets and a blind opacity of say ~90% then even Mercury could be inhabitable with this method? I'm thinking here the blind would also help protect the atmosphere from solar wind.

Conversely a big mirror array could help heat up Mars, but I was wondering with this method how far it could be extended, i.e whether a really massive array could heat up Titan etc?

 

[EarthlingX]

Just a thought : could we start from something small, then make it bigger ? Let it grow, not chop it apart to make it work ?

 

[Couerl]

does anyone know how large such a blind would have to be and how fast this would freeze the atmosphere, if indeed it would? Possible benefits are that you get to cool Venus down quicker and you could process what needs to be processed easier in solid form (just guessing here)? I envision that once we have Venus the way we like we could then lower the opacity of the blind to say ~50%.

Hi, well it's of course ridiculous, but the diameter of Venus is 12k km and a 500km disk approx. 6x the diameter of Venus sun ward should do it. The real question though is how much you would need to block? 100% would freeze out Venus fairly quickly I imagine, (100 years?) but that shouldn't be the goal. The goal would be to shade just enough to trigger a generalized climate change and cool the planet and I don't really know what kind of math is necessary or if it is even possible. (well it should be eventually with good computer modeling).. Say we shaded 20% along the equator with a ribbon around 10 km wide and 1000 km long, that might be enough but, we are talking about changing the climate of another planet artificially and even under the best circumstances such change would take place over thousands and thousands of years and not suddenly be "earth like". Neither mars nor Venus will be "terraformed" any time in your lives or your great, great, great grand kids lives or theirs either. The likelihood of these kinds of things is on par with cockroaches suddenly getting smart and taking us over. :lol:

 

[neutrino78x]

This is one of the advantages of Venus, it has a magnetic field.

True, but that only protects you from particulate radiation; it does not protect you from electromagnetic radiation.

The economy for either mission really requires (as EarthlingX pointed out in an earlier post) mining asteroids:

I definitely disagree with this. Again, with Mars, you can reach the surface now, before doing any terraforming. This means that you have access to all the resources on the surface of Mars. You can construct habitats and other structures using the Martian soil. You have access to the water that is in the Martian soil.

But these techniques could be developed in LEO at the ISS, with samples returned to it by unmanned vehicles. This will be required anyway if we are ever planning on a sustained presence in space over the long term.

True, I agree.

Being able to boost water into orbit at 1/6 G makes a HUGE difference from hauling it, or H2 and O2 up from Earth.

Yes it does, but on Mars, you already have the water there. On Venus, you have to get from somewhere else.

--Brian

 

[rockett]

True, but that only protects you from particulate radiation; it does not protect you from electromagnetic radiation.

Ever heard of a "Faraday cage"? Relatively simple structure, light too. EMI protection is low tech, light wieght, and easy to do. Not much more involved than the shielding on a microwave oven.

I definitely disagree with this. Again, with Mars, you can reach the surface now, before doing any terraforming. This means that you have access to all the resources on the surface of Mars. You can construct habitats and other structures using the Martian soil. You have access to the water that is in the Martian soil.

Lunar water is cheaper. Water extracted from Venus' atmosphere cheaper yet. For the mass of a single machine hauled to Mars to do construction work, you could build an entire Venus habitat almost.

Yes it does, but on Mars, you already have the water there. On Venus, you have to get from somewhere else.

Air. One of the simplest reactions uses Sodium Hydroxide, but there are others, for instance those using the CO2 in the atmosphere, Hydrogen harvested from solar wind, perhaps.

 

[EarthlingX]

Just a couple of questions, to chew on :
- where are the nearest resources from LEO dV wise, or expressed in dV required to get there ?
- what are closest targets we can get to with current, or 5 year time technology ?
- what is missing ?

 

[rockett]

Just a couple of questions, to chew on :
- where are the nearest resources from LEO dV wise, or expressed in dV required to get there ?
- what are closest targets we can get to with current, or 5 year time technology ?
- what is missing ?

Unless I read it wrong, Aten class asteroids seem to be the easiest. As it happens, those have an orbit mostly between Earth and Venus.
http://www.resonancepub.com/ssdj200111131.pdf

This paper addressed a lot of those questions.

 

[neutrino78x]

I endorse terraforming Venus, however, in terms of how the two planets are right now, I think Mars is more suitable for colonization. Mainly because of the accessibility of the surface of Mars. It is true that Venus also has the CO2 atmosphere, which could be used to exact oxygen via the Sabatier reaction, but you still can't use the Venusian surface for construction, until the terraforming lowers the temperature and pressure. So, basically, any large structure you put on Venus, or in the Venusian atmosphere, will have to built somewhere else, whereas on Mars, you can construct things out of the Martian soil.

Mars also has ice just as the Moon does. It has huge polar ice caps, and there is also permafrost all over the planet.

I would say the biggest advantage with Venus is not the atmosphere, but the gravity, it has like 88 or 90 percent the gravity of Earth. But, again, to access the surface, you first have to spend a long time terraforming it, whereas the surface is already accessible on Mars.

We could go to Mars, and colonize it, with the technology of today.

--Brian

 

[Couerl]

You couldn't even light a match on Mars, never mind colonize it with today's technology and the problem isn't the technology per-se to begin with, it is one of practicality and native resources. :geek:

I keep hearing about all these space miners and smelters and iron ore processor ships and all kinds of other crap, but the last time I fired up my welding torch it took some air to get it lit! Just how much air does anyone think an ore processor and iron smelter use to begin with and where are you going to get it? :lol:

 

[rockett]

So, basically, any large structure you put on Venus, or in the Venusian atmosphere, will have to built somewhere else,

Frankly, you overcomplicate the issue. Think light. Think dirigible. An earlier post suggested linking blimps into a colony, not a bad idea.

whereas on Mars, you can construct things out of the Martian soil.

This is assumed, not proven. You can't just berm it up and call it a shelter. You would still require structural support elements, as much or more than a Venus balloon colony.

Mars also has ice just as the Moon does. It has huge polar ice caps, and there is also permafrost all over the planet.

As I pointed out before, atmospheric extraction is even easier than "mining" water.

I would say the biggest advantage with Venus is not the atmosphere, but the gravity, it has like 88 or 90 percent the gravity of Earth. But, again, to access the surface, you first have to spend a long time terraforming it, whereas the surface is already accessible on Mars.

Spoken like a true flatlander.

We could go to Mars, and colonize it, with the technology of today.

Not entirely true. There would still be a lot of work to be done, to:
1. Design the process for constructing shelters. This would have to be foolproof, even a small flaw is deadly on Mars. Even the best simulations don't always match up to the real thing, in real conditions.
2. Design the machines to build your shelters.
3. Minimize the mass penalties.
4. Get them to Mars.

Venus balloon technology would be far less complex, for example:
http://www.space.com/businesstechnology/technology/venus_dare_021113.html

 

[rockett]

I keep hearing about all these space miners and smelters and iron ore processor ships and all kinds of other crap, but the last time I fired up my welding torch it took some air to get it lit! Just how much air does anyone think an ore processor and iron smelter use to begin with and where are you going to get it? :lol:

Not needed. In fact, the good news is, you wouldn't have slag from oxidization.

 

[neutrino78x]

You couldn't [...] colonize [Mars] with today's technology and the problem isn't the technology per-se to begin with, it is one of practicality and native resources. :geek:

Sure you could, you guys have to go buy the book The Case for Mars and read it, Zubrin has a doctorate in nuclear engineering and a master's degree in Aeronautics and Astronautics, and was an engineer at Martin Marietta for years, so he knows his stuff.

The key is that you use the resources native to where you are going. Mars has water, a CO2 atmosphere, soil and gravity. You can generate fuel, drinking water, and breathable air from the Martian environment. You can grow plants hydroponically.

You also don't try to build the USS Enterprise NCC-1701D before you go on a space mission.

I keep hearing about all these space miners and smelters and iron ore processor ships and all kinds of other crap, but the last time I fired up my welding torch it took some air to get it lit! Just how much air does anyone think an ore processor and iron smelter use to begin with and where are you going to get it? :lol:

That's one type of welding, but there is also electric welding. The civilian shipyard workers used that a lot to work on the submarine when I was in the USN. All you need is a power supply.

Ore processing, to my knowledge, is mainly a matter of heat. In space you just have a big mirror, and focus the heat of the sun with it. Or you could use a nuclear reactor to generate a lot of electric current, and use that to melt stuff. Or use the reactor to make microwaves. I'm not sure why electric heat is not used a lot more in industry on Earth. I would imagine it is because so much industry has been shipped off to 3rd world countries.

--Brian

 

[neutrino78x]

Frankly, you overcomplicate the issue. Think light. Think dirigible. An earlier post suggested linking blimps into a colony, not a bad idea.

I agree about thinking light, but you still have the issue that you cannot construct buildings using the materials available in the Venusian atmosphere.

whereas on Mars, you can construct things out of the Martian soil.

This is assumed, not proven. You can't just berm it up and call it a shelter. You would still require structural support elements, as much or more than a Venus balloon colony.

It isn't proven? So you're suggesting that mankind never built a building before the advent of modern machinery? It is unproven in the sense that we haven't done it on Mars yet. However, the basic concept has been around since time immemorial. Unfortunately the Mars Society home page isn't working for me right now, but yes, concrete can be created on Mars, and bricks can be made the same way the Egyptians made brick in the desert.

As I pointed out before, atmospheric extraction is even easier than "mining" water.

Well Mars has a CO2 atmosphere also. So if it is easy there, it is easy on Mars.

2. Design the machines to build your shelters.

Men would build them, by hand, just as they did in ancient Egypt. Eventually, yes, it would be good to construct/send machines for this purpose, but the initial structures, beyond the landing Habitat Modules, would be made by hand.

Venus balloon technology would be far less complex, for example:

But you can't build a balloon on Venus from the indigenous materials on Venus.

--Brian

 

[rockett]

I agree about thinking light, but you still have the issue that you cannot construct buildings using the materials available in the Venusian atmosphere.

Well, if you are going to get picky, use the lftover carbon from processing CO2 to make cabon fiber, and eventually nanotubes.

It isn't proven? So you're suggesting that mankind never built a building before the advent of modern machinery? It is unproven in the sense that we haven't done it on Mars yet. However, the basic concept has been around since time immemorial. Unfortunately the Mars Society home page isn't working for me right now, but yes, concrete can be created on Mars, and bricks can be made the same way the Egyptians made brick in the desert.

:lol: You have got to be joking, right? MUD BRICKS??? Sure, I would believe those are airtight enough to sustain an Earth normal pressure on Mars (at less than 1% of Earth normal). I wouldn't risk my life on it.

Well Mars has a CO2 atmosphere also. So if it is easy there, it is easy on Mars.

Yep, it sure does, at less than 1% the density.

Men would build them, by hand, just as they did in ancient Egypt. Eventually, yes, it would be good to construct/send machines for this purpose, but the initial structures, beyond the landing Habitat Modules, would be made by hand.

Do you even have the foggiest idea of what you are saying? In a pressure suit???? The problems of doing physical work in space suits are well documented. The best we have today aren't capable of doing what you are asking. The astronauts would very quickly exhaust themselves. In addition, on Mars you would be at risk of holing the suit and conductance heat loss. Though the picture of "colonists" playing in the mud in pressure suits is too funny. :lol:

 

[Couerl]

Hi, I just wanted to say that this thread has now officially become funny! :lol:

 

[neutrino78x]

I agree about thinking light, but you still have the issue that you cannot construct buildings using the materials available in the Venusian atmosphere.

Well, if you are going to get picky, use the lftover carbon from processing CO2 to make cabon fiber, and eventually nanotubes.

Ok, you still can't make steel, iron, etc. You need access to the surface for that. Teraforming already has to have fixed the atmosphere before you get to that step. Hence, Mars can be done with current technology, Venus can't.

:lol: You have got to be joking, right? MUD BRICKS??? Sure, I would believe those are airtight enough to sustain an Earth normal pressure on Mars (at less than 1% of Earth normal). I wouldn't risk my life on it.

Do you realize how thin some of the walls were on the Apollo 11 capsule?

Sure, it might slowly leak air, but you're continually making air by converting it from the atmosphere.

Well Mars has a CO2 atmosphere also. So if it is easy there, it is easy on Mars.

Yep, it sure does, at less than 1% the density.

Zubrin has demonstrated a machine, using 19th century technology, which takes CO2 in, at Mars pressure, and reacts it with hydrogen to get water, and splits that to get oxygen. And, again, you have access to the Martian surface.

Men would build them, by hand, just as they did in ancient Egypt. Eventually, yes, it would be good to construct/send machines for this purpose, but the initial structures, beyond the landing Habitat Modules, would be made by hand.

Do you even have the foggiest idea of what you are saying? In a pressure suit???? The problems of doing physical work in space suits are well documented. The best we have today aren't capable of doing what you are asking.

I strongly question that. They used tools on the moon rocks. Men routinely use tools and do complex mechanical tasks in space. They repaired Hubble in a pressure suit. Mars suits would be more flexible because there is an atmosphere.

If you insist, they can always bring a robot such as dextre (probably a more advanced version).

I am all about working smarter, not harder. Still, it is not that difficult a task. You would shovel the Martian soil into a mold, heat the bricks, place them, put mortar in between, etc. Men have been doing this since time immemorial. You suggest that I am over complicating things, yet you claim that basic, proven construction techniques could not be used. You want to wait until we have Star Trek level technology before we go to Mars. One wonders how many centuries will pass before you send a mission?

This paper from the Mars Society:

http://www.marssociety.org/portal/TMS_L ... arris_2004

in the book On to Mars 2, describes how they did this very thing at the Mars simulation research station in Canada.It took them 64 hours, as opposed to 6 hours without the space suits.

As they say in the Star Trek: The Next Generation Technical Manual, "if you could press a button to make a starship, you wouldn't have to...".

--Brian

 

[neutrino78x]

Actually Robonaut is more what I was thinking of.

--Brian

 

[rockett]

Ok, you still can't make steel, iron, etc. You need access to the surface for that. Teraforming already has to have fixed the atmosphere before you get to that step. Hence, Mars can be done with current technology, Venus can't.

WHY would you want steel or iron for constructing a floating habitat? That's just silly. :lol:

Do you realize how thin some of the walls were on the Apollo 11 capsule? Sure, it might slowly leak air, but you're continually making air by converting it from the atmosphere.

They were quite strong on the Apollo capsule, it had to survive re-entry, remember? At any rate you would need more than that on Mars, -radiation. Apollo was NEVER intended to be inhabited for more than a week. You are talking about YEARS.

Zubrin has demonstrated a machine, using 19th century technology, which takes CO2 in, at Mars pressure, and reacts it with hydrogen to get water, and splits that to get oxygen. And, again, you have access to the Martian surface.

Not the same as something that has to work in the real world, under extreme conditions. I could do that with a chemistry set.

I strongly question that. They used tools on the moon rocks. Men routinely use tools and do complex mechanical tasks in space. They repaired Hubble in a pressure suit. Mars suits would be more flexible because there is an atmosphere.

You still obviously still have not read the astronaut's accounts (or heard the interviews) of those experiences. Once again, do your research. As for Mar's atmosphere, it's no more help than a vacuum at 1% Earth normal pressure.

If you insist, they can always bring a robot such as dextre (probably a more advanced version).

So we finally get an admission machines will be needed.

I am all about working smarter, not harder. Still, it is not that difficult a task. You would shovel the Martian soil into a mold, heat the bricks, place them, put mortar in between, etc. Men have been doing this since time immemorial.

Again, read the accounts. From Apollo and the spacewalks.

You suggest that I am over complicating things, yet you claim that basic, proven construction techniques could not be used. You want to wait until we have Star Trek level technology before we go to Mars. One wonders how many centuries will pass before you send a mission?

Not at all. They are just not practical. Machines don't use air, water, and supplies. ALL OF WHICH have to be boosted to Mars initially. Manual labor=higher consumption rate.

This paper from the Mars Society:

http://www.marssociety.org/portal/TMS_L ... arris_2004

in the book On to Mars 2, describes how they did this very thing at the Mars simulation research station in Canada.It took them 64 hours, as opposed to 6 hours without the space suits.

Don't you even READ your own articles?
Here's a quote:

To explore this possibility Crew 22 aimed to manually construct a barrel vault with a one meter inner radius, using local stone and sand under simulation constraints. Portland cement and hydrated lime were the only imported materials. Construction lasted for 64.5 man-hours in Sim, and six man-hours out of Sim for comparison.

1. 64.5 HOURS for a 1 meter barrel vault. In case you don't know it, that's ONLY 39 inches. Hardly a habitat.
2. Portland cement and hydrated lime - Ever gone to Home Depot and picked up a few bags? If not, try it. That's a LOT of mass to "import" to Mars.
3. Simulation is ONLY that! We know NOTHING about what it is really like there yet. Think about the variations of soil on Earth (or the moon for that matter). We have only sampled a very few, very small areas, and analyzed them on Mars. Odds are very good that you would land somewhere that made your "simulation" worthless.
4. I saw nothing documented that these experiments were done at Mars temperatures and pressures. If they were not, they are worthless.