Life on Earth is at the ever-increasing risk of being wiped out by a disaster such as sudden global warming,
nuclear war, a genetically engineered virus or other dangers ... I think the human race has no future if it doesn't go into space.
" Another of his famous quotes reiterates his position that we need to get off the planet relatively soon.
"I don't think the human race will survive the next 1,000 years unless we spread into space."
