Biosphere 2

Biosphere 2 in Oracle, Arizona, is a vast glass-and-steel research complex created as a materially closed ecological system where humans, farming, technology, and multiple living environments could function together with minimal outside exchange. Launched in 1984 and built from 1987 to 1991, it contained seven biome areas and highly specialized engineering, including airtight construction and variable-volume “lungs.” Two human closure missions tested its original purpose, revealing both successes and serious difficulties, from coral reproduction and surviving biodiversity to hunger, oxygen decline, pest outbreaks, and management conflict. It later shifted to university research and remains the largest closed ecological system ever created.

Saddlebrooke, Arizona · United States