Lending a hand
All spacesuit gloves stiffen and fill with gas during an astronaut spacewalk, also known as extravehicular activity, or EVA. This pressure production is required to keep astronauts alive in space, and current spacesuits provide one-third of an atmosphere, which is sufficient to ensure astronaut well-being. But the pressurized gloves in a pressurized spacesuit make it very difficult, and often painful, for astronauts to grasp objects during an EVA, which can last up to eight hours each day. Not surprisingly, the most common type of injury reported by astronauts involved in EVA work is hand-related, including a condition known as fingernail delamination, in which the nail completely detaches from the nail bed. As designers seek to make spacesuits more comfortable, they are exploring the causes of injuries like fingernail delamination. Until recently, researchers suspected that finger length might play a role because astronauts’ fingers push against thimble-like structures inside the tips...