However, they have to attach themselves so they don't float around and bump into something. Generally, astronauts are scheduled for eight hours of sleep … Inside both crew cabins is a sleeping bag and a large window to look out in space. Space Station crews usually sleep in sleeping bags. Each one is just big enough for one person. Each crew cabin is just big enough for one person. Sleeping in space is an important part of space medicine and mission planning, with impacts on the health, capabilities and morale of astronauts. Currently, Space Station crews have three astronauts living and working in space for months at a time. On the Space Station there are two small crew cabins. Space station crews usually sleep in sleeping bags located in small crew cabins.