They do that with good reason. Introduce life to Mars and you are now studying a planet that has been contaminated by modern Earth life, and it will be extremely hard to find out if it had life already before you got there, and whether or not you have made the existing life on Mars extinct by introducing modern micro-organisms from Earth.

If anyone thinks it is possible for humans to go to Mars without introducing new organisms to it, reflect that the skin flora alone of a human being has 1000 species in 19 phyla, some not well known yet, and over a trillion individual organisms. Just your skin. More and more species are turning out to be extremophiles, with hidden capabilities, don't need to live in extreme places at all, just capabilities that they have from the past. There is increasing modern evidence that some of these species could survive on some niches on Mars just as it is now without any terraforming of Mars and without any special adapatation of the organism, just transfer the organism to Mars and it could survive and colonize all available niches on the planet quite quickly. That is if the niches exist - but - e.g. thin salty films sub surface (which may well exist in places on Mars), or the water vapor that briefly condenses in evening and morning from the air on Mars - both been shown to be possible habitats or existing modern micro-organisms. And many organisms form spores that are amazingly resistant even to everything that mars can throw at them.

And - the COSPAR guidelines require that Mars be protected in the event of a hard landing. A hard landing on Mars of a human occupied spacecraft would deposit human bodies directly on the surface - immediate huge Mars contamination, hard to see how that could ever be reversed.

I think it is a scam, they said they received 80,000 applications @ $38?, that is around $3 million they have made.

Hmm. This contamination issue sounds extremely serious -- do you think it might be that we should never send humans to the Mars surface, except perhaps if we can conclusively rule out the existence of any native life first (which, if it is true, would still be a long ways off), or until terraforming is started, if we decide to go down that route? As it's an unalterable fact that humans are biological. So however you send them, you WILL contaminate Mars. Period. So sending humans to the surface effectively means ending whatever studies one might want to do on a pristine Martian biological environment permanently. So you'd better get all science requiring that done before the first human boot goes on the ground. And if you look at how many decades we've been studying the Earth's environment for, then think about that much time for Mars... and you see that human boots shouldn't be on the ground for a similarly vast amount of time.

Also, you mention orbital colonies -- how much would it cost to build one around Mars? How long would it take? Consider the difficulty and complexity involved in building the ISS, just a few hundred miles over our heads. Now multiply that distance by something in the neighborhood of a million. What would you think of a plan by any entity to get such a base by the year 2045? Do you think any government, or coalition of governments, working with technology available now or that could be developed within that time frame, could pull it off even if private companies couldn't? Would 2045 still be too optimistic? What happens when you throw in political crap? Politics, it seems, at least in a place like the US, tends to impede things more than make them happen. And as far as I can tell, nobody has a serious plan to actually do this orbital colony thing -- right now it seems like it's mostly conjectural and speculative. What would it take to turn that into real plans? How likely is it that it could be done?

I'd also wonder: what about, for a very first mission, to start out with something real simple -- just a "fly-by" of the planet and that's it? This would itself be valuable experience for future missions. Still want some trained personnel on there, but could it potentially be doable in 20 years, perhaps even by a private?

And what about radiation? This seems like a big problem. New research (http://www.kurzweilai.net/cosmic-radiation-found-harmful-to-astronauts-during-space-travel) shows that in addition to the known risks of cancer, radiation may trigger degenerative, irreversible brain disease. What to do about this new wrinkle? This would seem to not only put a "safe" (for some suitable definition of that word) trip out of the reach of privates but out of the reach of our current technological know-how. Someone in an orbital colony on a long-term mission could have a really serious problem here. It's not like the ISS near Earth -- Earth has a magnetic field of useful strength, Mars doesn't. And an orbital colony doesn't even have the help of the thin Martian atmosphere, whatever use that may be.

It'd seem the best bet for orbital colonies would be the two little moons. One could imagine drilling into them to get away from radiation... but how much would it take to launch heavy drilling/digging equipment? Man, with these kind of considerations it'd seem that even a "BetterMarsMission 2048" would still be waaaay too optimistic a timescale. Heck, even without rad. concerns -- consider all the technology that'd be required to extract, process materials from the moons, etc. Suddenly your orbital base faces a challenge WAY bigger than the ISS... and it's about 1,000,000 times further away. That stuff's gotta get to Mars somehow... !!! It seems like it'd be an even bigger technical challenge than landing people on the surface and returning them. How likely is it that it could be done with realistic budgets and a not-too-long-but-not-as-short-as-10-years timescale?

Do you believe there could be any prospect for a manned mission by any entity that could be feasibly done with a time frame of 20 years as opposed to 10? How about 30? Orbital base instead of land colony, even w/trained personnel? Odds?

Okay first for the cost of actually getting there, in rocket fuel, Mars is quite easy to get to if you go to the Mars orbit rather than the surface. It is actually slightly easier than going to the Moon. So it is not that hard to get reasonably large habitats to Mars orbit.

The cost is actually rather enormous...

We did not send large habitats to the Moon and doing so wold not be cheap. The delta-v required to get into orbit around Mars is not less than landing on the Moon unless you allow for aerobraking, which for a large habitat is not going to be very practical.

ou were right. I edited my post.