"Think about what happens on Earth when you throw up. You throw up and you have a bag of something ho..." — 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.

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.

To be one of the world's top space robotic arm operators is a necessary skill for an astronaut, but it doesn't have much carry-over.