text: why isn't their a "green house" on the space station? since the space station's main purpose to be a stepping stone toward colonization of the moon and mars, why don't they try to grow their own food and be more self sufficient?   also, if they created such a room it would make the sterile life on the station more tolerable.  the plants would remove co2 and add o2. first of all, the international space station has no natural supply of oxygen, the oxygen supply comes from machines that generate it. second of all, you cannot keep soil in one pack in microgravity, everything there would just appear as clumps of things