They won’t return — but, that doesn’t necessarily mean that they’ll die early. It’s really not a lot different from getting on the Mayflower, for a one-way trip to the New World.
I made that argument to a friend today and he replied “Yeah, except for the food, water, and air thing.” Well, yeah, I sez, but at least there won’t be any hostile natives trying to stick pointy things into yer epidermis. “How do you know?” he asked. Hmm...
“It’s really not a lot different from getting on the Mayflower, for a one-way trip to the New World.”
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Mars is not quite like the “New World”. One can not go out and smell the roses, or do anything else for that matter.