Its not as hard as contemperary scientist make it out to be.. i mean.. sure it seems hard due to say.. like mars.. has more carbon dioxide..but thats because they always think they need complex means to make it posible.. although sometimes it can be easy to use simple ways.. for example.. radiator.. you can use a scarf to tie up the hose.. or.. use ductape to tie a exhaust pipe to the car.. you dont always need a mechanic.. same complies with that.. you dont need complex machines to turn all that carbon dioxide into oxygen and to form an equal balance..we have a more simple natural way..its the micro organisms.. its the plants.. its the means we have now.. we can send micro organisms to mars in a jar with a space rover if need be. whats stopping us? the scientist think inside the box with their "advanced" understanding of things.. but sometimes it takes thinking outside of the box to fix stuff. and you can find examples everywhere. feel free to comment