Biosphere 2 is basically an Earth system science research facility located in Oracle, Arizona that serves as a center for research, outreach, teaching, and lifelong learning about the planet, its living systems, and its place in the universe. The 3.14-acre structure remains the largest closed system ever created. Unfortunately, it was only used twice for its original intended purposes as a closed-system experiment: once from 1991 to 1993, and the second time from March to September 1994. Continue reading for two more videos and additional information.
Both attempts ran into problems, including low amounts of food / oxygen, animal / plant die-offs, group dynamic tensions among the resident crew, outside politics, and a power struggle over management as well as the direction of the project. Nevertheless, the closure experiments set world records in closed ecological systems, agricultural production, health improvements with the high nutrient and low caloric diet the crew followed. The second closure experiment achieved total food sufficiency and did not require injection of oxygen.