"To be on my very first spacewalk, to be outside, and to have contamination in my suit to the point t..." — Chris Hadfield

When you're on one of the Caribbean islands, sometimes it's hard to picture how they fit in with the rest, but when you see them all joined together like a necklace from space, you see the natural geographic connectedness of them all.

Think about what happens on Earth when you throw up. You throw up and you have a bag of something horrible and then you throw it away, but if I have this bag, what am I going to do with it? This bag is going to stay with me in space for months, so we want a really good barf bag.

The International Space Station is a phenomenal laboratory, an unparalleled test bed for new invention and discovery. Yet I often thought, while silently gazing out the window at Earth, that the actual legacy of humanity's attempts to step into space will be a better understanding of our current planet and how to take care of it.

The communities and countries best at using energy to optimize a microclimate for human life are also the ones whose people have the longest average lifespans. Canada, Sweden, and Iceland - places with inhospitable winter weather - are frontrunners in sustaining human health and life.