Space is incredibly dangerous, in case you didn’t know.  Harmful radiation, bitter cold, low pressure, no air, and no gravity make for a very difficult environment to survive in.  Even though a space capsule is pressurized with breathable air, protected with radiation shields, and warmed to a comfortable temperature, the effects of microgravity are still damaging to the human body.  We know that astronauts lose bone mass rapidly, have to exercise to keep their muscles active, but what other effects does microgravity have on the body? For one, without gravity to clear your sinuses, they get a bit clogged in...