Imagine we could accelerate continuously at 1 g-what we're comfortable with on good old terra firma-to the midpoint of our voyage, and decelerate continuously at 1 g until we arrive at our destination. It would take a day to get to Mars, a week and a half to Pluto, a year to the Oort Cloud, and a few years to the nearest stars.

Those afraid of the universe as it really is, those who pretend to nonexistent knowledge and envision a Cosmos centered on human beings will prefer the fleeting comforts of superstition. They avoid rather than confront the world. But those with the courage to explore the weave and structure of the Cosmos, even where it differs profoundly from their wishes and prejudices, will penetrate its deepest mysteries.

Arguments from authority carry little weight – authorities have made mistakes in the past. They will do so again in the future. Perhaps a better way to say it is that in science there are no authorities; at most, there are experts.

I'm only a four-dimensional creature. Haven't got a clue how to visualise infinity. Even Einstein hadn't. I know because I asked him

You mean am I for it or against it? You think this is a key question I'm going to be asked on Vega, and you want to make sure I give the right answer? Okay. Overpopulation is why I'm in favor of homosexuality and a celibate clergy. A celibate clergy is an especially good idea, because it tends to suppress any hereditary propensity toward fanaticism.

All colours are arbitrary.

There is never only ONE of anything in nature.