Could a man-made, airtight ecosystem be created to sustain people without the need for external material resources? Could the entire thing be powered by energy from the sun or a fusion reaction?
As humanity gears for space exploration, we are getting increasingly interested in technologies that help us reuse and recycle resources in space. On the International Space Station (ISS) water is already being recycled for drinking. In such a habitat, plants can exchange carbon dioxide for oxygen and provide food by using waste as fertilizer.
There was an experiment called Biosphere 2 which was a materially enclosed but energetically open habitat on earth. It unfortunately failed, but it had a pretty good run for a while. That was 20 years ago. What have we learned since?
How do we create a functional self-sustaining habitat where people can survive and thrive in space?