11 Craziest Things About Living In Space
8. It Screws Their Sleep

Floating about in zero gravity might seem like the ultimate in comfort, but getting you shut-eye in space isn't as easy as you might think.
For a start, on the ISS there's no such thing as a good night's sleep, as the astronauts experience 16 sunrises and sunsets in the space of an earth day, making an ISS "day" just 90 minutes long. This, understandably throws their circadian rhythms right out of whack, making it difficult to fall asleep and stay asleep for any length of time.
Another problem is the sheer amount of noise a space station makes. Every little part of it is usually spinning, whirring, beeping and clicking and, until they get used to the noise, not even the sleeping pills and ear plugs are enough to cancel it out.
On the plus side, there's no chance that the snores of your crew mates will keep you awake, as weightlessness has been found to reduce sleep apnoea and stop snoring. If you really can't sleep, then each if the cabins has a huge window, so you can get a bit of stargazing done.
At the beginning of the working cycle, mission control plays music selected for the enjoyment of a particular astronaut to wake them up. Wonder if it's ever a bit of Bowie?