Reader Erica asks, “What do astronauts do when they get an itch on their face while in their space suits?”

Astronauts have a few tricks up their bulky sleeves for dealing with facial discomfort when tucked inside their suits (known as Extravehicular Mobility Units, or EMUs, during the shuttle era). As NASA’s Phil West demonstrates in this video, space walkers can use the microphone in their helmet as an improvised scratching post. Astronauts also sometimes attach patches of velcro to the inside of their helmets so they can scratch. 

Sometimes, an itch is the least of an astronaut’s problems. It can get pretty warm in those EMUs, and an astronaut’s body heat and sweat can fog up the face shield on the helmet, leaving space walkers visually impaired. To combat this, the insides of the helmets get treated with an anti-fogging chemical. In 2011, Endeavour shuttle astronaut Andrew Feustel was on a space walk outside the International Space Station when some of that anti-fogger got in his eye, leaving it stung and watery. Feustel was able to relieve some of his pain by rubbing it against his suit’s Valsalva device, a foam block attached to the interior of the helmet. Astronauts use the device to block their nose when they need to use the Valsalva maneuver to readjust pressure. You can see ESA astronaut Sam Cristoforetti using the device here