To date, scientists have not succeeded in the circulation of substances in orbital stations. The decisive role in creating the circulation of substances in such expeditions is assigned to the processes of biosynthesis. The functions of supplying the crew with food, water and oxygen, as well as removing and processing metabolic products and maintaining the required parameters of the crew’s habitat on a ship, station, etc. are assigned to the so-called life support systems (LSS): gas composition supply systems, supply systems water, waste disposal systems, etc.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.