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.

Almost everything I do when I approach an operational problem comes from the time I've been in space. It's a way of organizing your thoughts. We use problem-solving; what we call "what-if-ing." What if this happened? What would we do? We go over plan B, C, D, E, F, and whatever else, depending on the criticality of what we're doing. This kind of thing can be applied almost everywhere, even at home.

You're always under the microscope, and you don't know which mission you're going to get. It's a surprise.

When I saw the Earth from above, personally, as a spacecraft operator, it certainly reinforced and drove home the fact that there's one place where we can live right now. The seven billion of us are sharing a wonderful planet, and it's an absolute privilege to see it from above.

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.

The prerequisite that people have a scientific or engineering degree or a medical degree limits the number of female astronauts. Right now, still, we have about 20 per cent of people who have that prerequisite who are female. So hey, girls: Embrace the very fun career of science and technology. Look at computer science. That's what I did.

Most astronauts are very down-to-earth people. Many of us, three-quarters, have an engineering degree, and we have a very Cartesian, rational approach to things. You don't go and get swept off your feet. That's not your job and that's not why you're hired. So if you get so mesmerized that you forget to do what you're supposed to do, whether it's to open the cargo door of the space shuttle or configure something inside, then you should not be there as a professional operator.