Some billionaire has come out.....putting up cash....to rocket a couple off to Mars. The deal? Well....there's no showers once you take off, and there's eighteen months ahead of you. The liquids you drink? After two days....you more less start recycling your urine and sucking sweat off your body....to help the machine give you more liquid. For this eighteen month period....there's no more fresh water. Your team? Just you and your wife. That's it.
You have an area of sixty cubic feet, limited food, and limited places to stand or sleep. And you have to avoid any confrontations or arguments for this entire mission.
Who would want to slurp urine and sweat for months? Who would want to sit in a tightly-fitted area with their spouse for months? Who would want to eat mostly all packaged food and juicey-juice for months and months?
I just can't think of any fool who would raise their hand for this kind of mission.
You can imagine about half-way through the trip....Harvey calls back to mission-control.....Wanda has gone ballistic and almost half-killed him last night. He needs an exit operation immediately Mission-control spends four hours talking to Wanda, and now realize that she's nuts. So the question is....does Mission-control tell Wanda to go ahead and kill Harvey, or do they inform Harvey of her condition, and then suggest he might ought to kill her while he has a chance?
This is the kind of stuff that the Star Trek guys just never had to worry about. Kirk would have said no-way to drinking urine for months, or not being able to take a bath.