More sleeping in space

From sleeping on the Moon we move onto sleeping on to sleeping on the ISS. They have much better arrangements than the lunar lander. They have little compartments with a sleeping bag tethered to the wall, a computer they can use for email and whatnot, and a door they can close for privacy and darkness.

One interesting detail -- the air needs to be well circulated or, in the weightlessness, a bubble of exhaled carbon dioxide will form around their heads as they sleep.