I hate to be a nay-sayer, but it is highly doubtful that we will ever "colonize" mars. Setting up scientific research stations is a possibility, however resources are the biggest setback we face insofar as setting up a whole colony on another planet. Oil is, of course, declining worldwide, and we'll be hard pressed to find another kind of fuel that can generate as much energy and as cheaply as rocket fuel to propel shuttles past escape velocity.

With the monumental amount of money needed to transport a sufficient number of personnel and machines to Mars to even begin construction (even with the gradual habitat structure drops proposed, it would still take decades to build up a real colony), I doubt any one nation will be able to bear the full cost; designing, building and launching satellites cost enough money as it is. Perhaps the EU will be able to fund such a project, but the US? Doubtful, especially with the budget crisis we face today.

Let's put this in perspective: The cost of building the launchers and the Apollo spacecraft alone came to a total of roughly 67.5 billion dollars. Granted, this was in a timespan between about 1959 to the mid 70's, so if we were to be generous and use 1968 as a point of reference for inflation change, this cost would come out to be $419,070,607,461.38 today. And the missions themselves cost billions of dollars more - see the attached link for more expenditure figures.

Now, that cost is nothing compared to what we've spent in Iraq, however this was a figure for the journey to the moon. Mars is 35 million miles from earth - at its closest point, no less. It would take 6 months to arrive there with our current technology, as opposed to the four days it took for the Apollo shuttle to reach the moon. Obviously this brings in the issue of muscle and bone atrophy; even if humans find some way to enter a "stasis" like the Sci-Fi flicks, their muscles would still break down while suspended in zero gravity. Thus, the astronauts would need to stay awake and exercise to prevent muscle atrophy, as well as a number of other health issues that accompany extended exposure to zero gravity. This means they would need food and water (since they recycle their urine for oxygen, rather than for drinking water) for the whole 6 month journey, as well as supplies for when they arrive on the planet. This mandates a larger shuttle for storage space, which necessitates larger, more powerful rockets to carry them out of earth's gravitational pull.

Bone atrophy is even worse than muscle atrophy, because exercise does not reverse the calcium and bone cell loss caused by zero gravity. Some may propose that a rotating space craft may induce artificial gravity to prevent this, however such technology is highly controversial and there isn't much consensus on how the hell that would work in the first place. And, of course, this will require even more costly R&D;.

An interesting video on Youtube is a History Channel documentary called The Universe on colonizing space, and it outlines a number of valid complications in the plan to colonize Mars (Search "The Universe: Colonizing Space" - it's a 5 part video series. Very fascinating).

Solar winds also pose a problem that will require specialized equipment to survive; intense waves of radiation can wipe out a crew if they're not prepared; satellites that detect a solar wind would have to be posted in space to relay the information to the crew, and a special bunker would have to be built within the shuttle so they could escape the deadly radiation. This would also be an issue on Mars, since it has a very, very weak magnetic field to stop the solar wind. A bunker would have to be constructed there as well. In fact, the colonies might have to be built underground to shield the people from cosmic rays and violent sandstorms; living on the surface with prolonged exposure to radiation could render the inhabitants infertile - not a good way to run a colony.

Colonies built on Mars would have to have supplies flown in to keep the inhabitants alive while they figure out some way to obtain food from the planet. In fact, the first "colony" to be built on Mars would probably be no more than a single structure where a crew of 4 people live. There are a number of psychological problems that come with this, however on Devon Island in the Canadian Arctic they've already built a simulation ground that will be similar to this scenario: one small structure, a small crew to live there for months simulating scientific research. This might be a good training ground to prepare for that.

Also, going back to the gravity issue, Mars' gravity is 1/3 that of earth's; this could cause complications for the humans living on the planet. Their bone cell count would decrease, they would lose calcium, and if they live there for long enough, their bodies would have acclimated too much to the lower gravity to return to earth and function normally.

Once more, I'm not saying missions to Mars are impossible. But colonizing Mars is a whole other story, and we really should be focusing on the missions themselves rather than get ahead of ourselves and assume that we'll even get that far. Anything is possible, however at this moment the future for such elaborate scientific expeditions looks rather bleak, simply because of our economic situation. We really need to get things together here on earth before we spend a huge amount of money on colonizing another planet. The only feasible way we could fund such a project would be if the nations of the world joined in larger unions similar to the EU, to pool economies and funds. That is, unless the US recovers from its current rut enough to delve into these experimental and very costly expeditions.

Some advocate a colony on Mars 1) as 'insurance' against a cosmic calamity on earth (such as a comet impact) or 2) as a 'stepping stone' for space exploration.

Perhaps astronauts will visit Mars temporarily, as they now visit the International Space Station. But a permanent, self-sustaining colony would require a tremendous amount of infrastructure: farming, medical facilities, educational facilities, factories, housing, power generation, etc. And due to fuel requirements and the hazards of traversing Mars' gravity and atmosphere, construction material will have to come from Martian soil.

In the event of a catastrophe on Earth, at best only a few people could be evacuated to such a colony.

For humans, round-trip interplanetary travel beyond Mars isn't feasible with current technology, so a 'stepping stone' isn't needed.

A permanent colony on Mars would be prohibitively expensive. For the present it is more practical to invest in improvements on Earth.

Did I make it clear that it will cost BILLIONS to proceed with Mars missions, which will be DEDUCTED FROM YOUR PAYCHECK?

Lunar and Martian colonization are necessary, even if we generate them only as temporary colonies designed to be abandoned once our technology reaches the levels we need for mass interplanetary or interstellar flight. Terran locales, even the ISS, are inefficient when it comes to deep-space and interplanetary observation; the solar wind, atmospheric corruption and magnetic interference of the ionosphere combine to make even our most sensitive instruments mostly focus on filtering out the "noise" to obtain the "signal." A lunar outpost would eliminate both atmospheric and magnetic issues, since the atmosphere on the moon is non-existent and the magnetic force of Luna is orders less than Earth's. Mars would also help with the solar wind problem, since it is far enough away that the effect would be attenuated.

Additionally, we currently have only two gravitic environments for chemical and physical experimentation, normal (i.e. terrestrial) and micro/null (i.e. spacebound). Colonization of either Mars or Luna (preferably both) would permit the addition of two low-gee environments to the list of experimental stations. This could result in hundreds if not thousands of advances in science, medicine, pharmaceuticals, and technology.

While the colonization of other worlds is not something that is critical to survival, it is an important step in scientific discovery and even perhaps a possible long-term solution to overcrowding. While a self-sustaining colony on another planetary body, whether it be Mars or the Moon, is a long way off in terms of technological and environmental advancement every project must start somewhere.

However, there must be some profit for humanity, beyond simple scientific curiosity, to motivate man to spend billions of dollars (or any other currency) to first put man (and or woman) on a planet, then launch the materials needed for those settlers to survive.

So while I believe that colonization of the Moon, then eventually Mars, is something that should be done, it is not something that must be done. Nor is it entirely unthinkable to consider that it may not be done; at least not in our collective lifetimes. That being said I find it just as likely, and very possible, that a Lunar colony and a manned Martian landing will occur within the next fifty years.

Big Picture- Yes.

We will get to a point where our population and its needs exceed what this planet can provide.

We will either change the plantes to accomodate us, or even change ourselves genetically to adapt [ I just left the gentetic modification posts, so the idea is still fresh on my mind]

But yes, in the long run its a part of our species' version of evolution, since we don't really have natural selection, it seems our phases of evolution are controlled by our very wants and needs.

A little more than a century ago, human flight seemed impossible. Now our big concern is what we'll have to pay for carry-on luggage.

The colonization of Mars is a matter of 'when', not 'if'. It is inevitable that humankind will make progress toward interplanetary travel. A colony on Mars is a necessary step toward this goal.

Even the physicist Stephen Hawking says that we need to get to other planets in case an asteroid hits earth or someone trips and hits the big red "nuke everything" button. At some point we're going to run out of land, and people always like a challenge.

If you look at the big BIG picture, as the whole universe, and then zoom down on earth and into the lives of men, it seems only necessary.

People want to live and live comfortably. Pack too many people into one place and you get social disorder caused my claustrophobia and the overwhelmingly complex networks that people weave. Population will only go up as medicine saves more and more, and morals are refined or, maybe locked-down would be a better way to put it, to keep people alive, all people. This is due in part by the lack of attention to the philosophy of living and dying, and too strict of religions.

We are already running out of fossil fuels or the means to extract more from places that do have fossil fuels. On that note, burning of fossil fuels is links to the changes in climates around the world, we all know. The world isn't such a bright place anymore.

The only thing for us to do is move on to another planet. It's not like we're doing something unimaginable. It's like moving from Europe to North America, it's just another land.

Abstracted from "The Case for Colonizing Mars" by Robert Zubrin

1. Mars is rich in carbon, nitrogen, hydrogen and oxygen.

2. Mars has the potential for wind-generated power as well as solar power.

3. Mars has an atmosphere thick enough to protect crops grown on the surface from solar flare.

4. Martian colonists will be able to live on the surface, not in tunnels, and move about freely and grow crops in the light of day.

5. Mars may have concentrated mineral ores, with much greater concentrations of precious metal ores readily available than is currently the case on Earth.

6. Deuterium, the heavy isotope of hydrogen is 6x more common on Mars and worth over US$10000/kg.

7. Extreme shortage and a pro-tech culture will drive ingenuity to produce wave after wave of invention in fields such as energy production, automation and robotics, biotechnology, and other areas.

8. Mars is to the new age of exploration as North America was to the last.