Water is a precious commodity everywhere, and that's especially true in space. All water must travel from Earth, so astronauts are careful to preserve it. They use damp, soapy towelettes for washing. Often they step into a shower stall that employs a vacuum handle to suction the soap off their bodies. Astronauts even use a special NASA toothpaste that can be swallowed, making rinsing obsolete. Pictured here is astronaut Michael E. Fossum washing his hair on the middeck of the Space Shuttle Discovery while it is docked with the International Space Station.