Most of the modules in the International Space Station have four sides and they’re put together that way so the people can work on a flat plane; wall, floor, another wall, or the ceiling. All you have to do is turn yourself around and your reference changes. People always ask about sleeping in space. Do you lie down? Not really, because it doesn’t matter. You don’t have the sensation of lying down, so you just sit in your sleeping bag.
The sleeping stations are like phone booths, but pretty comfy and you can sleep in any orientation in them. Astronauts don’t have any sensation that tells them that they’re upside down. In the same time sleeping booths are small offices with a laptops, toys, books, and clothes in them.
One of the things that astronauts also do is exercise. They need to exercise because they lose bone density and muscle mass while they’re up there, and that’s a result of not having to fight against gravity. They keep themselves in a shape with a bike, treadmill and a weight lifting machine. The bike doesn’t have a seat, because the astronauts don’t sit down. They actually haven’t sat down for six months.
The bike is not firmly attached to the wall because if they start putting forces on the space station it’s going to make the solar panels bounce around a little bit. So to prevent that, the machines in the space station bounce around a little bit and that way they don’t put any forces onto the structure of the spacecraft and out to the solar panels.
There is also a module where everybody meets in the morning. After you wash your face, and brush your teeth, you want to find something for breakfast. There are all sorts of foods in the kitchen module: drinks, meat, eggs, vegetables, cereals, bread, snacks, side dishes, and some power bars. Some of this food is dehydrated, some of it is readymade.
There are spacesuits ready and primed up to go outside (the astronauts call it space walking) in case they need to do anything outside of the space station. Most of the things they do outside are repairs. There are lot of electrical boxes and machinery that are outside and sometimes they don’t work quite right because the space is actually extremely cold vacuum.
The spacesuits are pretty big and part of the reason they’re so big and bulky is because of their backside. The backpack and the suit weigh about 136 kilograms. Luckily in space nothing really weighs anything so you don’t feel the weight.