2:01:31The Spaceship That Has to Become Earth
A two hour argument that the hard part of interstellar travel is not distance, it is replacing every service Earth performs for free. The video inventories seven of them, gravity, atmosphere, radiation shielding, thermal control, water, food, and waste, with the real numbers: 224 m of radius to fake one g at 2 rpm, 15 to 25 kW of grow lighting per person, 98% water recovery that still bleeds 2% every cycle. It anchors the whole case in Biosphere 2, where oxygen fell from 20.9% to 14.4% in sixteen months because soil microbes ate it and the concrete quietly absorbed the carbon dioxide that would have shown the imbalance. The last forty minutes leave the machinery for the harder problem: confinement psychology, generational knowledge transfer, and children born into a world their parents chose. Its conclusion is that the engineering goal is boredom, because a habitat only works when the people inside can forget it exists.



















































































