Astronauts are allowed to take only one bag with personal belongings to space. By making the most out of this bag, it can provide more emotional comfort, sense of belonging and functionality to the personal area in a spaceship.
Comparable to nomadic lifestyles, living on a journey requires emotional stability and a certain mindset to let things go, which means the things you do have, become more important. Just like a home contains things with emotional value, so does this bag. It has an emotional value and represents home in a portable form.