Can’t worry about things that you can’t control.

Yes. People died. And people will die. Any time people venture into the unknown, there is a cost. Space has never been safe. No frontier is safe. When it comes to Mars, we must get used to death.

Happiness is death by complacency.

You cannot teach instinct.

All the people who have doubted me, professors, investors, politicians, journalists, they all said the same thing, “I’ll believe it when I see it.” But that’s backwards. Belief comes first. Only then can you see it.