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."

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.

I am definitely a little more nervous for my colleagues when I'm working at mission control than I am myself, on the shuttle.

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.

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.

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."