Volunteers sought for simulated Mars mission, with a duration of 520 days

At our current level of technology Mars remains an extremely challenging destination, with launch windows only every 780 days and a journey time of six months or more, one way. I created a map a while back showing a comparison of the distance between Earth and the Moon vs. Earth and Mars, as without the comparison it can be difficult to imagine. The distance from the Earth to the Moon is represented by the blue line going down the street a bit, and the distance from Earth to Mars is in red, making a journey that takes over an hour by car (on the map, that is).


View House to school in a larger map

This is why the volunteers needed to simulate a Mars mission will need to undergo the mission for a total of 520 days - 250 days there, 30 days on the ground, and 240 days back. The numbers themselves show the problem with Mars, as we haven't even had people in space for that length of time yet. The longest a human has ever been in space has been 437 days, and that was in Low Earth Orbit. Since most of this time would be spent in 0g, it could prove to be damaging to the physiology of those on the mission.

So why not embark on a one-way mission then, to live off the land as many advocate? This is actually the best plan we have at the moment for seriously colonizing Mars, since a mission to such a distant location in such a large gravity well becomes exponentially more difficult if we have to plan for a return mission on top of everything else. A one-way mission allows all the resources at our disposal to be used for the trip there and living off the land after arrival.

BUT

If that's true then the same argument can also be made for the Moon. If one-way plus living off the land is the best and cheapest way to colonize Mars then it's also the cheapest way to colonize the Moon as well. The Moon would also technically not be a permanent one-way mission since those on the surface would take with them plans to construct a return vehicle, and would also be helped by mission control step by step as communication between the Earth and the Moon only has a delay of about 2.5 seconds. The return trip could also happen at any time whereas one from Mars would have to be timed to the very infrequent launch windows that open up between Earth and Mars...and of course the return trip would only require a few days of supplies for the astronauts compared to at least 240 days for those on the way back from Mars.

So why not make the argument for a one-way trip to the Moon instead?