Scott Kelly came back from the International Space Station and said his clothing felt weird. It floats around you when there's no gravity, you see.
Which raises all kinds of other questions, many of them addressed in a book by NASA advisor Ariel Waldman called What's It Like In Space?
Things we just do mindlessly here on Earth, like sneeze and sleep and use hot sauce (!) can become issues when you're weightless.
Ariel Waldman joins us with some of the highlights.