requires flawless delivery of air, food, and water, flawless temperature control, and flawless waste handling for that entire period. This adds enormous mass and hence increases the technical problems. Available cabin space would be minimal, and communications would be very slow. Moreover, no one has ever spent that much time continually in space, and very long-term zero-gravity effects on the body could be quite substantial
There are many possibilities for potentially fatal problems: List of spaceflight-related accidents and incidents
Mars mission poses greater risk to human life than Nasa would allow
Crew on Dennis Tito's Mars mission will face unprecedented dangers – and time is too tight for the usual test flights
Ian Sample, science correspondent
guardian.co.uk, Friday 1 March 2013 09.36 EST
... Tito has assembled an experienced group to plan and advise on the adventure, they must still develop life-support systems and radiation protection, and heat shields to withstand a re-entry that will be twice as fast as any other return to Earth. Then they must buy and modify a rocket and capsule for the mission, with no time for test flights ... "On survival rations you can do it, but there's not much margin for error," said Ojha. Fuel, liquid oxygen and water tanks would be held in a service module attached behind the crew capsule ... On a typical voyage to and from Mars – which would be longer than Tito's planned trip – estimates suggest the crew has a 10% chance of experiencing at least one fatal SEP event, and more than a 30% chance of exposure to a blast that would kill 35% of people in 50 days. Fortunately, the proposed launch date of 5 January 2018 is when solar activity is near its lowest, and when SEPs are correspondingly less intense and less frequent ...
= new reply since forum marked as read