One possible scenario for future manned exploration of Mars is that the astronauts would be given what amounts to a "one-way ticket" with enough fuel and supplies to get them there and keep them alive but with NO plans to return them to earth.
This may strike our modern sinsibilities as an absurd requirement for a mission, and yet it is not much different from what prospect was faced by ocean voyagers during the "age of exploration" right here on earth.
Comments? If you were able to qualify, would you be willing to do this?