The landmark glass terrarium known as Biosphere 2, built as a self-sustaining environment for humans 20 years ago, and the 1,650 acres (668 hectares) surrounding the Arizona research site were sold to a home developer for $50 million (37 million EUR).
Texas billionaire Ed Bass spent more than $200 million (147 million EUR) building Biosphere 2 near Oracle. The site attracted global attention in 1991, when eight people were sealed inside to conduct a two-year experiment in self-sufficiency.
The buyer, CDO Ranching & Development, L.P., said the 3.1 acre (1.25 hectare) building will remain open to researchers and tours for now. The sale was announced Monday by Jerry A. Hawkins, vice president of real estate firm CB Richard Ellis Tucson.
Pinal County officials have approved plans to build 1,500 new homes and a resort hotel on the land.
Columbia University began managing the complex in 1996 and later pledged to expand research and programs there, but that relationship ended in 2003.
The University of Arizona hopes to lease the terrarium for large-scale climate experiments, said Joaquin Ruiz, dean of the College of Science.