In Arizona, nature is diverse and dramatic. The state's Tonto Natural Bridge State Park is home to the world's largest natural travertine bridge, where visitors can hike and explore its unparalleled ...

In the early 1990s, eight people agreed to vanish from the world and live for two years inside a sealed glass habitat in the ...

ORACLE, Ariz. — Plopped in the Sonoran Desert, just outside Tucson, Ariz., sits a massive, multilevel greenhouse that's probably best known as the inspiration for a Pauly Shore movie. A slick, stepped ...

From a distance, Biosphere 2 emerges from the cacti and creosote of the Sonoran desert like a gleaming oasis, a colony of glass and bright white structures. Despite being just outside Tucson, Arizona, ...

On Sept. 26, 1991, a grand experiment began. Eight people were locked in the giant terrarium, Biosphere II, to live without physical contact with the outside world for two years. Biosphere II was a ...

The study of Earth science isn’t just for students who are interested in how our planet works. It’s also for those who are passionate about addressing urgent global challenges such as climate change, ...