The ship ran on a state-of-the-art technobabble drive. So long as there was a semi-plausible but ultimately meaningless explanation, accepted by the crew on faith, everything was fine. The life support used ultra-dense biomimetic arrays to replenish oxygen. They were propelled either by solar sails or nuclear fusion. Maybe both. No one cared to question it. Everyone knew what happened when someone doubted; they had seen the Perseus fall out of the sky. All it took was one word to punch a hole through the hull faster than you could say “I do believe in fairies.” One traitorous word: “Why?”
Initially, this was going to be a string of technobabble trying to explain something. I like this better.