Much of the cost of a voyage to Mars will be spent on coming home again. If the fuel for the return is carried on the ship, this greatly increases the mass of the ship, which in turn requires even more fuel...I agree. And I note that I floated the same idea on this blog 4 years ago:
[I]f the radiation problems cannot be adequately resolved then the longevity of astronauts signing up for a Mars round trip would be severely compromised in any case. As cruel as it may sound, the astronauts would probably best use their remaining time living and working on Mars rather than dying at home.
If it sounds unrealistic to suggest that astronauts would be willing to leave home never to return alive, then consider the results of several informal surveys I and several colleagues have conducted recently. One of my peers in Arizona recently accompanied a group of scientists and engineers from the Jet Propulsion Laboratory on a geological field trip. During the day, he asked how many would be willing to go on a one-way mission into space. Every member of the group raised his hand....
We might want to restrict the voyage to older astronauts, whose longevity is limited in any case. Here again, I have found a significant fraction of scientists older than 65 who would be willing to live out their remaining years on the red planet or elsewhere....
But I must say, when I saw the headline about a 90-year-old "Explorer of Mars," an idea that occurred to me was having a one-way mission, sending some quite old persons to Mars, with no way to bring them back. I was assuming he'd be in favor of sending a man to Mars and imagined him saying I'm 90, send me! I'm going to die pretty soon anyway. I'd like to have a shot at making it to Mars. And you can just leave me there!
Would it be wrong to have a mission like that? Why is it that young people take the most risks with their lives? Shouldn't the oldest people take the most daring risks, since they've lived the greater part of their lives and therefore risk less of it?
By the way, the NYT published an offensively ageist illustration with its op-ed.