No one ever accomplished anything great sitting down.

If you haven't learned to ride a bike by the time your peer group has, then suddenly it's an embarrassment and you'll avoid opportunities where you're expected to ride a bike. And then it starts shaping your behaviour. Reading is much subtler, but much more destructive if you have not - for whatever reason - learned to read by the time you should.

I've been lucky enough to fly to space twice.

From space, the Bahamas is the most beautiful place on Earth.

My favourite city for nightlife is Toronto, as it has such a multicultural feel, with so many different restaurants and theatres.

It's good to have a fear of heights. I mean, it's kind of crazy not to because if you just lean out a little bit and there's a gust of wind or somebody bumps you or something and you fall, you're splat.

Spaceflight isn't just about doing experiments, it's about an extension of human culture.