To date, there is not even agreement on whether large crews require more or less area per person than small crews. When the direction of this effect is ascertained, we can begin to explore the details of the relationship between crew size and spatial needs. Several questions emerge regarding how the space that is available should be allocated. There are numerous environmental factors which singularly are of only minor importance, but which together determine the quality of life in a spacecraft. Although few of these factors have yet posed serious problems, certain questions suggest themselves as deserving attention in extended spaceflight.
Food emerges as an important habitability consideration in many confinement situations.
Various studies indicate that an even greater emphasis is placed on food and on mealtime generally when individuals are confined. It will be important to determine what role food consumption, as a diversionary or social activity, will play in long duration spaceflight. Also, it will be important to determine how the use of food can be influenced by other environmental factors. For instance, it is likely that the greater the satisfaction with work and leisure activities, and the more prevalent the opportunity for social interactions, the less will be the interest in food. A psychophysical question was suggested by the astronauts of Skylab.