In a tidy house or office with a clean floor you can see immediately if someone has dropped something, a glasses case, for example. Lying on the floor, this object catches the eye, and everybody passing by will notice it. In the Space Station a number of factors make it very difficult to find something that is lost.
First of all, of course, zero gravity. The other day I had a ballpoint pen clipped to my trousers when I brushed past something and lost it. I noticed immediately, so I turned around quickly to pick it up. Nothing. My ballpoint pen was nowhere to be found, it had flown away, I didn't know in which direction, up, down; it could have been anywhere.
I began to accept the fact that I had lost it, but when I turned to proceed with my daily schedule I saw it in front of me, flying in the same direction I was moving. When it flew away it must have bounced on something, and kept going without waiting for me.
The Station is made of modules in which the working area is more or less rectangular, but ahead and behind; up and down; and even right and left there are multiple adaptors with hatches. As a consequence there are many corners in which things can hide.
Besides that, which wall is the floor? And which is the ceiling? In many places the four walls of the 'tube' that make a module are all the same, so everything is difficult to find.
For example, I do quite a lot of work in a module that is not in the main 'tube', but is attached to a side. You have to make a ninety-degree turn to enter that module from the others. Until then, everything is fine; when you enter, what is below you, you call 'the floor', and what is above, 'the ceiling'.
But sometimes you might come from the other direction on your trip along the tube, and make the turn. Now you find that the ceiling is the floor and vice-versa. Because of this, if I have left the computer switched on and attached to the wall, when I go back I always have to make a full turn to find it.
And, finally, there are so many things attached to all four walls. Describing it like this must make it sound untidy, with everything in the way, but it's a matter of necessity. The photo cameras can't be put away because we take a lot of pictures of the work we do with the experiments, and of the Earth as well. The cameras are all stuck in place with Velcro, together with a variety of lenses, flashes etc. Sometimes you need to turn three times to find the camera you are looking for.
Other items that are also in view are spare parts, food packages, bags full of clothes, etc. It is not that we use these things everyday, but there's no more room in the cupboards. The Station is not finished yet, and there won't be enough storage space to put everything away until all the planned modules have been connected.
One of the things that I use most frequently is a notebook where I take down information about the experiments. I carry it with me everywhere, I write down the precise hour at which I have changed the samples, the results, things to be aware of, etc.
This notebook has to come back to Earth with all this data; it will help the scientists to rebuild exactly how everything has happened. The first days this little notebook drove me crazy. I stuck on it, of course, a large piece of Velcro to help keep it from flying around. But at the end of the day, if it was not in the first place I searched then it took me a while to find it.
Now I've got used to leaving it in one of three different places, but at first it was a nuisance because I didn't know if I had dropped it somewhere else or if it had loosened itself from the Velcro and was floating around, in which case it could be just about anywhere.
Once I made the famous turn carrying the notebook in my hand, together with some books and other items. When I reached the workplace I didn't have the notebook anymore. I knew I must have lost it when I slightly hit the corner, so I went back immediately. It was nowhere to be found. After some frantic minutes – fearing that I would bitterly pay in delays by the end of the day - I found it in a little hidden corner. Thank heavens.
I forgot to mention an important factor in loosing things: the air stream. As everything floats, and because the air gets renewed and cleaned with fans and filters, anything that flies away tends to follow the direction of the air stream. The air stream actually helps more than hinders, contrary to what you may expect. If you have lost something small you only have to wait a couple of hours and you know where it will go: to the filter where the air enters the circulation system. We are already used to checking there every now and again: all kind of interesting things can be found.