This article from the British Medical Journal should give aspiring space tourists some food for thought. The basic gist: Traveling into the heavens is not really comparable, physically and medically, to Earth-bound travel. In fact, up until now, extreme physical fitness has been a major factor in how we select space travelers. What happens when less-fit people start flying? What happens to sick people? These are questions that matter a lot, given the fact that current astronauts report everything from reduced eyesight to potentially dangerous immune system changes. (Via The Inkfish blog)