Living in a Tin Can

Life aboard the ISS mixes frontier science with constant small absurdities. With no gravity to pull anything down, everything drifts — including the sweat on your face, which beads up and wobbles there instead of dripping off. Crews vacuum loose crumbs out of the air before they float into equipment.

The body suffers too. Muscles and bones waste away fast when nothing is pulling on them, so every astronaut works out about 2 hours a day on bungee-strapped treadmills and resistance machines just to come home able to walk.

Even the bathroom is high-tech. The toilet uses airflow instead of gravity to pull waste away, and developing one model cost about $23 million. Nothing is wasted: humidity, sweat, and even urine are captured and recycled into drinking water — filtered until it is cleaner than most tap water back home. In other words, the coffee a crew member drinks today may well return tomorrow as the water for the next pot.