The only hazard in this experiment is that there was no real sense of risk, which likely would affect the results tremendously. If they could have simulated loss of life somehow, that might give a more realistic view of how the confinement, and the isolation would have affected the astronauts.
I suspect they'll repeat in a few years with a capsule in orbit. If you're in orbit for 520 days, something's almost guaranteed to go wrong, so it'll be a good bit more realistic.
(I'm actually pretty sure I read about plans to do this around 2018 in orbit, but I can't find the article now. Anyone?)
No single crew has been in the ISS, without other non-radio human contact, for 520 days. In fact, no single person has been in space for that long, period. The record at the ISS is 198 days; at MIR, 437[1].
The differences between an orbital mars voyage simulation and the ISS would be that the ISS gets resupply shipments and isn't on a 26 minute radio response delay with ground control.
It's cool, but utterly pointless. Valeri Polyakov spent 437 days in orbit in one mission, in which he was routinely tested.
> Polyakov's mood stabilized to pre-flight levels between the second and fourteenth month of his mission.
So I really don't see a point of a test of this length, if mood stabilizes to pre-flight levels during the second month then there's no point of a test beyond two-months in duration if this holds true for multiple people. Given the number of astronauts and cosmonauts that have been on prolonged missions the data should be readily available to crunch.
Why bother isolating people for 520 days when you can crunch the data of hundreds of people isolated for months to gather the same data. It's a complete waste of money that could have been spent on real research.
33 men survived 69 days trapped in a mine after a collapse. Big groups have bigger risks of social cohesion failing. I think it speaks when 33 men not trained for the situation got through it fine.
Top that in risk, stress, quantity of participants and isolation. It was 16 days before they knew anybody was even looking to rescue them. Top that one for stress.
The only hazard in this experiment is that there was no real sense of risk, which likely would affect the results tremendously. If they could have simulated loss of life somehow, that might give a more realistic view of how the confinement, and the isolation would have affected the astronauts.
Nonetheless, a great experiment!