Space, it says, is big. Really big. You just won't believe how mind-bogglingly huge it is. I mean you may think it's a long walk down to the chemist's, but that's just peanuts to space! Listen!.................and so on and so forth.
Seriously, considering how ridiculously huge the universe is, it seems a bit preposterous that only one tiny little planet within the entirety of it would have life on it. Unless this is just a really, REALLY early stage in the Universe's lifespan, where this planet was just a starting point and our population is eventually meant to settle the entire expanses of the universe..... but that's highly unlikely.