Biosphere 2

Biosphere 2 is an Earth systems science research facility, owned by the University of Arizona since 2011. Its mission is to serve as a center for research, outreach, teaching, and lifelong learning about Earth, its living systems, and its place in the universe

It is a 3.14-acre structure originally built to be an artificial, materially closed ecological system, Constructed between 1987 and 1991, it is the largest closed system created.

Biosphere 2 contained representative biomes: a rainforest, an ocean with a coral reef, a mangrove wetlands, a savannah grassland, a fog desert, an agricultural system, a human habitat

Biosphere 2 had two closure experiments, Missions 1 and 2, during which the structure was sealed with researchers living inside. The first closed mission lasted from September 26, 1991 to September 26, 1993. The second mission began on March 6, 1994 but Mission 2 was ended prematurely on September 6, 1994.