You know how you always wanted to be an astronaut, because you really wanted to have an EVA jaunt in the great empty of space? Well, good luck with that: it'll make your fingernails fall off. Some astronauts actually pull their own fingernails off before heading into space to get it over with. It turns out that wide-handed astronauts are at the highest risk of "fingernail delamination." NASA's Astronaut Glove Challenge has been running for several years, but still the nails fall off.

In several cases, sustained pressure on the fingertips during EVAs caused intense pain and led to the astronauts' nails detaching from their nailbeds, a condition called fingernail delamination.

While this condition doesn't prevent astronauts from getting their work done, it can become a nuisance if the loose nails gets snagged inside the glove. Also, moisture inside the glove can lead to secondary bacterial or yeast infections in the exposed nailbeds, the study authors say.

If the nail falls off completely, it will eventually grow back, although it might be deformed.