Ventilation is needed to ensure we get air disbursed throughout the Station. Air stagnates without flow, so it is essential to have good ventilation so one doesn't end up in a bubble of CO2 by accident and then not be able to breathe.

Gravity on Earth provides a force that keeps our bones and muscles working. In the microgravity of space, our bones and muscles are not taxed, so they begin to atrophy.

The first 6 hours of being in orbit were a little difficult on my stomach. I think things just didn't know where to go!

Sunita Williams Quotes