Why is forced air circulation necessary on spaceships?

Without forced air circulation, it would be impossible to maintain a normal temperature on board the ship. The cosmonauts would breathe exhaled air, since in a state of weightlessness there is no convection, that is, no natural air circulation.

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.