Not that living on Earth will make you immortal or anything, but a terrifying MIT study calculates that a Martian colony founded using existing technology would start dying off after 68 days. And that’s assuming there are no complications. This is bad news for the privately-funded Mars One initiative, which aims to put a human colony on Mars by 2025 using existing technology.
But even assuming Mars One can address issues posed by short-term threats to human survival, like the food-to-oxygen ratio mentioned in the MIT study, there are other looming threats that the Mars One initiative is completely unprepared to address. One elephant in the room is Martian radiation, which could sentence all of the colonists to an early death. I say “could” because Mars One has proposed an answer to this concern (one mSv is equivalent to a year’s radiation exposure on Earth):
The 210-day trip results in radiation exposure of the crew of 386 +/- 61 mSv. On the surface, they will be exposed to about 11 mSv per year during their excursions on the surface of Mars. This means that the settlers will be able to spend about sixty years on Mars before reaching their career limit, with respect to ESA standards.
Mars One’s calculations are based almost exclusively on 2011 data from the Curiosity rover, and they rely on several optimistic assumptions: favorable space weather, a one-way trip (as a round trip could exceed lifetime radiation limits), and reliable shielding that would limit radiation exposure to actual excursions on the Martian surface. Mars One’s emphasis on lifetime radiation limits also downplays the potential effect of short-term radiation exposure; absorbing up to 447 times the normal per-year dose of radiation in 210 days could be hazardous, independent of the lifetime limit. So there are some unexplored issues here with radiation.
But the more immediately dangerous problem might actually be the technology behind Mars One itself. The relatively small-scale deployment of colony resources allows little room for spare parts and little margin of error; considering the 180-day launch window for future Mars missions and the 210-day trip beyond that point, this means that any technological malfunction could take over a year to correct. If that technological malfunction is related to life support or food production, it’s easy to imagine any number of horrifying scenarios.
Nobody said establishing a colony on Mars would be safe, but it’s very difficult—especially after the MIT study—to see Mars One’s 2025 timetable as anything but reckless. Traveling to Mars is an incredibly brave and competent thing to do, and it takes a rare person to do it. Painstakingly assembling a group of those rare people and sending them off to their deaths would do incalculable damage to future space colonization efforts. We need to develop a timetable based more on research and development and less on plausible fundraising targets and, to be frank, we probably need to land a manned Mars mission and create a sustainable lunar colony before we start thinking about sending people to permanently live on Mars. Yes, the human future lies with interplanetary colonization—but a cluster of deserted, corpse-filled habitat pods doesn’t really count as a colony.