Even if FTL travel is not possible...
And it takes 20-30 years to travel to the nearest star...
What if it is possible to extend the human (or alien) lifetimes to 1000 years...A realistic goal if we assume genetic manipulation and or nano-robot repair of damaged organs is possible. (Maybe not in our lifetimes, but in those of our grandchildren?)
Such a trip to and from the stars, might then be a bearable burdon on us (or them).
