While spending time in space, astronauts must be prepared to face an array of challenges, from technical issues with complicated equipment to the psychological stressors of being isolated and far from home.
But spaceflight also takes a toll on their bodies. Research has found astronauts’ weight-bearing bones lose between 1 and 1.5 percent mineral density, on average, for each month they spend without Earth’s gravity. Their muscles shrink, and some of their bodily fluids shift up into their heads, putting pressure on their eyes that can lead to vision problems.
In an effort to combat some of these physical effects, 12 volunteers are spending 60 days lying in bed in a French laboratory. They’re participating in a study called the Bed Rest with Artificial