High-tech Sleeping Bag Protects Astronauts’ Eyes from Damage in Space

The impact of a mission to space doesn’t just end with a lifelong aversion to astronaut ice cream. In reality, there are very real physical impacts to the body after prolonged exposure to zero gravity. Take, for example, the highly publicized height gain of two inches astronaut Scott Kelly experienced after his last mission. And while Kelly shrunk back to his former size within days of his return, there are some impacts of space travel that are more permanent. For years, scientists have documented the negative impacts of space on the eyes. On earth, gravity serves many purposes, but one little-known benefit is to suck fluids down back into the body after a person rises from bed each morning — a process that’s known as “unloading.” Because astronauts in zero gravity never really stand up, unloading doesn’t occur. Without it, scientists say more than a half-gallon of extra fluid collects in the head and applies pressure to the eyes, impacting eyesight along with it. According to the BBC, in 2005, astronaut John Phillips left Earth for the International Space Station with 20/20 vision and returned with 20/100.