I agree terraforming is a worthwhile goal, but the above statement is untrue. The number of domes that can be built is limited only by the surface area of the planet.

http://en.wikipedia.org/wiki/Paraterraforming

__________________
"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

I'm aware of that concept, I'm also aware of the monumental engineering challenges involved in getting a decent amount of land from it. A complex society has to be able to provide itself with basic supplies using only a fraction of its labour force, and that might not be possible if every plot of agricultural land requires a huge structure to be built and maintained around it.

If your entire population has to work full time just to feed itself, your development simply stops.

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"I worry that, especially as the Millennium edges nearer, pseudo-science and superstition will seem year by year more tempting, the siren song of unreason more sonorous and attractive." - Carl Sagan, 1995

The level of effort needed to build a geodesic dome is not great. An inflated dome is even simpler. And any manned structure in space will require maintainance. I don't see it as nearly the challenge of deveolping a sustainable enclosed ecosystem for such colonies. And certainly far, far, FAR less of an engineering and ecological challenge than terraforming a planet!

__________________
"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

As I understand it, many terrestrial plants can probably be grown at Mars surface pressures (or rather close to them), so an inflatable dome could be done "relatively" simply with essentially just enough pressure to hold the dome up, making fairly large scale agriculture more attractive (though tending would probably be done robotically).

Mike

By the time large-scale structures can be built on Mars, the maintainance will probably be largely automated as well, and the mining of materials and manufacture of parts will have to be at least partly automated. The initial construction will require automation anyway, since any construction crew on-site will need life-support while they're working, which will require at least a moderate-sized greenhouse. The fewer people involved at that point, the easier the logistics. But on Mars, the starter settlement need not be a totally closed ecosystem, as raw materials (CO2, small amounts of H2O) are closer than shipping them from Earth. As more advanced colony structures are built, closure efficiency will increase, if only to save energy.

__________________
"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

I disagree. “Terraforming” is necessarily on a scale too large to undertake anywhere in the foreseeable future. Almost by definition, an “Earthlike” planet will have to be the result of millions of years of evolving and changing life forms. There really is no shortcut.

They are artists because they are not qualified to be scientists. IMO, it is almost certain that Martian colonies will be underground, in excavated tunnels, or natural caves and lava tubes. The extent of the underground agricultural areas will be, by necessity, equal to the task of supporting the contemporary population.

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Reality: What a concept!……………………..><Ç(((Ç°>

Note he didn't say we'd start terraforming now, but rather to examine Mars with an eye towards future terraforming. Which is kind of a moot point; we'll be there gathering as much data as we can anyway, no matter what it's eventually used for.

Mars is never going to be Earthlike, it's not Earth. But a few centuries work could get it up to "human-habitable without artificial aids." Millions of years is nature's way. Humans have innovated quite a few shortcuts.

There are quite a number of people who are both.

Most likely some will, but that has nothing to do with population levels. And agriculture will still require sunlight; the level of shielding needed to produce viable food crops is, IIRC, much lower than that needed for human beings. Most food plants live only one growing season anyway, and can tolerate a bit of radiation and still survive well enough to produce food (I'm not sure, I think so. Anyone here an expert on radiobotany?) So growing crops aboveground is no problem.

__________________
"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort