The landmark glass terrarium known as Biosphere 2, which was built as a self-sustaining environment for humans 20 years ago, and the 1,650 acres surrounding the research site have been sold to a home developer for $50 million.
Texas billionaire Ed Bass spent more than $200 million 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 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.
Pinal County Supervisor Lionel Ruiz, whose district includes the Biosphere 2 land, said the development will be good for the area but must be approached cautiously.
"I don't want to see just a whole bunch of rooftops from Tucson all the way to Oracle," he told the Arizona Daily Star. "We want to see sustained communities and some open spaces and wildlife corridors. Like anything else, if they come in with proper plans, it'll make it a plus."
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.
In a statement, Bass said he was "hopeful that CDO will have success in attracting significant institutional participation in Biosphere 2 for research and educational purposes."