There is a sunrise or a sunset from space every 92 minutes so there is an incredible amount of beauty to see from up there.
Chris HadfieldMy favourite city is Moscow, because of its history, which I find fascinating. As I learned to speak Russian, it made it even more interesting.
Chris HadfieldOther anatomical changes associated with long-duration space flight are definitely negative: the immune system weakens, the heart shrinks because it doesn't have to strain against gravity, eyesight tends to degrade, sometimes markedly (no one's exactly sure why yet). The spine lengthens as the little sacs of fluid between the vertebrae expand, and bone mass decreases as the body sheds calcium. Without gravity, we don't need muscle and bone mass to support our own weight, which is what makes life in space so much fun but also so inherently bad for the human body, long-term.
Chris Hadfield