Deep in the Arizona desert near Oracle sits one of the strangest experiments ever built, a sealed, 3.14-acre glass and steel enclosure called Biosphere 2. Constructed between 1987 and 1991 at a cost of roughly $150 million, funded largely by Texas billionaire Edward Bass, it was designed to test whether humans could live inside a fully self-sustaining artificial ecosystem, complete with its own ocean, rainforest, desert, savannah and farmland. On 26 September 1991, four men and four women, known as biospherians, sealed themselves inside for what was meant to be a two-year mission. What followed became one of the most closely watched, and ultimately most controversial, science experiments of the decade. The unexpected chemistry between soil microbes and curing concrete remains a valuable cautionary lesson for engineers today, showing how even carefully designed closed systems can fail in ways that only become apparent under real, sustained conditions.
Get breaking news anytime, anywhere. Download the TOI app now!
