Chris Hadfield

The best simulator for spacewalking is underwater - it allows full visuals and body movement in 3D. Virtual reality is good, too, and has some advantages, like full Station simulation, not just part. Like all simulators, they have parts that are wrong and misleading: an important thing to remember when preparing for reality.

There are no wishy-washy astronauts. You don't get up there by being uncaring and blase. And whatever gave you the sense of tenacity and purpose to get that far in life is absolutely reaffirmed and deepened by the experience itself.

One place that I looked at a lot from space and which looks alluring is New Zealand, especially the North Island. It's a big broad valley with a river flowing through it, and you can see the wine-making dryness of the land.

By irreducibly complex I mean a single system composed of several well-matched, interacting parts that contribute to the basic function, wherein the removal of any one of the parts causes the system to effectively cease functioning.