One peculiarity of an astronaut's job is that we do everything in public. Also, you don't want to make a mistake. In the best case, it's an embarrassment, in the worst, death. That's also part of the training. They teach you to think like an astronaut, like they do with a pilot, a military man, a fireman. You dissociate in your mind the gravity of the consequences of your mistake.

Many people don't know that you don't spend 10 minutes without using a satellite. Or that agriculture is managed from space. Banking, too. The space program is like our airports and highways. It's not a luxury. It's part of the fabric of the modern world.

Half of one per cent of the U.S. budget is space-related stuff. In Canada, we spend more on dog foodScreen Shot 2015-08-19 at 2.39.35 PM. Space flight is intrinsically international and very modern. It's like a co-op. Every country provides services. In Canada, we have a focus on robotics in the shuttle and space station. In exchange, we get research time for our scientists and astronauts' flights. Our contribution is as a junior partner.

In space, you can't see the borders. It doesn't look like a map. We're all like kids fighting in a sandbox, on the political and human side of it. The International Space Station was built in orbit. Each piece hurtled into space at eight kilometres per second. From an engineering point of view, it's madness. It's also a feat of policy - Russia, the U.S., Germany and Japan working together. Do you realize what that means? These countries were sending nukes to each other a generation ago. Space does that. It gives us that amazing big picture.

Space is our tool to take care of the world. From space, we know the Earth is fragile, and we can follow oil spills and forest fires, and monitor the environment and save it. The needs of remote communities and the needs of astronauts are similar. Canada is a country that is big and has a lot of people living in faraway places. Physicians in remote areas need to have contact with more senior colleagues. We depend on telehealth for advice, X-rays, labs. At the most simple technical level, space technology contributes to remote health care.

There's always this message I want to give kids: Everybody has a dream, but it's often very vague. We owe it to ourselves to identify it and not be afraid of it. Even if it's crazy and unachievable. The importance of finding your dreams doesn't lie in the fact that it gives you a target that you have to achieve, but it gives you a direction. When you set it into motion, things happen. That's the message I want to give my kids. If your dream isn't scary, it's not big enough. Sure, use your head, get a job. But don't lose sight of wonder.

One peculiarity of an astronaut's job is that we do everything in public. Also, you don't want to make a mistake. In the best case, it's an embarrassment, in the worst, death. That's also part of the training. They teach you to think like an astronaut, like they do with a pilot, a military man, a fireman. You dissociate in your mind the gravity of the consequences of your mistake.