Definitely you don't become famous by doing something bad; that's a professional death sentence. You remember that whatever you do, someone will be watching, and you study all the time. It sounds terrible, but you get used to it. I'm 45, and I'm still at school, essentially.

My husband and I don't worry about each other the way we might if we didn't have similar jobs. I sometimes get an email where he tells me he's heading off on a mission to do terrain avoidance 50 feet above the ground at 500 knots. And I just say, "Okay, have a good flight."

Will we go explore? Absolutely. That's what humans have been doing since we left the caves in Ethiopia. Why? Because this is part of our nature. We're curious. We want to push the envelope. That will never stop. We will see people on Mars, hopefully in our lifetime. My hope is that the endeavour is so large, so complex, so technically challenging, so demanding and so uplifting, that it will be done with a consortium of nations. I hope the people who do set foot on Mars will do so for all mankind, and not just one nation in particular.

Most people here don't have a wide emotional range. It's just the type of people astronauts are, they're required to be level.

On the day a country decides not to invest a cent in innovation, discovery or exploration, that country decides to be a tributary to others.

You're less apprehensive when you know what to expect. Also, the first flight is very important in this performance-driven culture I work in; it establishes your reputation. If you don't do well, it's probably your last flight.

The science behind Interstellar is interesting, because some of it is absolutely real astrophysics and orbital mechanics, some of it is theoretical physics, and some of it is completely Hollywood. When a science fiction movie is based on plausible science, it's really good.