As a life-long of reader "hard" sci-fi, making me a renown expert, IMHO:
How will humans survive the radiation?
How will humans remain mentally healthy?
I don't think we can feasibly become space faring until those challenges, and probably some others, are addressed.
Edit: Oh, I just had an idea. How do people with Asperger's deal with isolation, boredom, continuous contact with a handful of other people? Maybe there's a subgroup of people who are mentally perfectly adapted for space travel.
How will humans survive the radiation?
How will humans remain mentally healthy?
I don't think we can feasibly become space faring until those challenges, and probably some others, are addressed.
Edit: Oh, I just had an idea. How do people with Asperger's deal with isolation, boredom, continuous contact with a handful of other people? Maybe there's a subgroup of people who are mentally perfectly adapted for space travel.