Mary Roach was determined to write the definitive 'sex in space chapter' in the history of space journalism. And although she gets into pondering what the pitfalls of sex in zero gravity might entail, her book "Packing for Mars: The Curious Science of Life in the Void" also broaches issues that most earthbound humans have never considered.
For example, try to imagine the tricky process of taking a shower when you're used to water droplets falling in an orderly cascade from a faucet above your head. What happens when that water condenses into a big blob of liquid, unwilling to fall anywhere? And what other bodily processes involving falling water might prove difficult in space? Roach explains the mechanics and preparation behind all sorts of space activities in her new book.