Inside the evolution of Biosphere 2, from '90s punchline to scientific playground

Trees grow against the windows at Biosphere 2 on June 20, 2025 in Oracle, Ariz., U.S.

The venture, privately funded to start, is now run by the University of Arizona. And today, scientists there are quietly plugging away at research they hope will help us all adapt to the Biosphere 1 — that is Earth, and the climate change we are causing to it.

(Image credit: Caitlin O'Hara)