Babylon 5, Season 1: Signs and Portents

Mary Ann Cramer:
Is it worth it? Should we just pull back? Forget the whole thing as a bad idea, and take care of our own problems, at home.

Sinclair:
No. We have to stay here. And there's a simple reason why. Ask ten different scientists about the environment, population control, genetics, and you'll get ten different answers, but there's one thing every scientist on the planet agrees on. Whether it happens in a hundred years or a thousand years or a million years, eventually our Sun will grow cold and go out. When that happens, it won't just take us. It'll take Marilyn Monroe, and Lao-Tzu, and Einstein, and Morobuto, and Buddy Holly, and Aristophanes…[and] all of this…all of this…was for nothing. Unless we go to the stars.