Life in a Spaceship

Necessary living conditions must be maintained in the cabin of a spaceship: specific pressure, humidity, temperature, lighting, absorption of carbon dioxide, supply of oxygen, food, and the removal of the body's waste products. These are complex questions and may be settled in different ways depending on the duration and objectives of the flight. For comparatively short flights around the earth these problems have been solved: physical, chemical, and mechanical methods are quite acceptable. Apparently the same methods may be used for longer flights of man, to the moon for instance. It will be different when man flies to Mars or Venus, which might call for many weeks. Here biological methods will most probably have to be used. Maybe a closed cycle system will be devised so that waste products will not be removed but reprocessed and rendered fit for the astronaut s use. In other words, a process would be created to reproduce in miniature what takes place on a gigantic scale on our planet. This calls for some kind of unique hothouse, with plants to provide man with rood and cleanse the air of carbon dioxide. The size of all this has to be small enough to fit inside the cabin. Probably, the most economic means for air regeneration would be green algae photosynthesis. Research has shown that 2½ kilograms of green algae will supply sufficient oxygen for one person.