In any new situation, whether it involves an elevator or a rocket ship, you will almost certainly be viewed in one of three ways. As a minus one: actively harmful, someone who creates problems. Or as a zero: your impact is neutral and doesn't tip the balance one way or the other. Or you'll be seen as a plus one: someone who actively adds value. Everyone wants to be a plus one, of course. But proclaiming your plus-oneness at the outset almost guarantees you'll be perceived as a minus one, regardless of the skills you bring to the table or how you actually perform.

No one ever accomplished anything great sitting down.

One Chief Astronaut used to make a point of phoning the front desk at the clinic where applicants are sent for medical testing, to find out which ones treated the staff well-and which ones stood out in a bad way. The nurses and clinic staff have seen a whole lot of astronauts over the years, and they know what the wrong stuff looks like. A person with a superiority complex might unwittingly, right there in the waiting room, quash his or her chances of ever going to space.

The rough and ready improvisational quality to life on board the International Space Station is reminiscent of a long trip in a sailboat: privacy and fresh produce are in short supply, hygiene is basic, and a fair amount of the crew's time is spent just on maintaining and repairing the craft.

It’s not enough to shelve your own competitive streak. You have to try, consciously, to help others succeed.

Our three big emergencies are fire, loss of pressurization or contaminated atmosphere. Any of those things in a spaceship are very deadly and time critical. Everybody's trained, but I'm the commander of the ship, and it's up to me to decide.

In all of the movie portrayals, a spacewalking suit seems sort of insignificant, like a pair of shorts and a T-shirt. No one thinks much about it. But it's a spaceship, not a spacesuit, an entire life-support mechanism that's incredibly complex and cumbersome. It's very difficult to put on and off. You have to run it the whole time you are wearing it, and it redefines how you move. It's like if you put on a wetsuit and a snowmobile suit and froze yourself solid and then tried to go and do work.