 Why was space exploration so important?
They were something more—and something less—they were, in short, humanity's hopes for survival! The starlanes between Earth and her potential colonies were rough on the men who traveled them now. Earth couldn't turn out enough starmen in the schools, so promising kids were being shipped out for training as cadets on their twelfth birthday. But something had happened to the exploration party fifteen years back, and to the more recent ship under Hennessy that was sent to check up. Earth had ordered him to detour here, after leaving his load of deep-sleep stored colonists on Official World 71, to check on any sign of Hennessy. We've scoured this planet by infra-red, and there was no sign of native villages or culture.
 they were running out of time on Earth
 it was trendy to live on a different planet  there was a lot of interest in life on other planets  they were running out of time on Earth  people were trying to leave the wars on Earth