Glass Pyramids of Biosphere 2

The white domes and glass pyramids of Biosphere 2 rise high above the desert outside Tucson, Arizona. In the early 1990s, it housed eight people for two years as part of a notoriously failed experiment in self-sufficiency. Now it’s a research station maintained by the University of Arizona.

In its second year, the largest indoor soil weathering experiment involves three million pounds of soil piled in huge mounds and sprayed regularly with water. “It’s like Groundhog Day,” says Peter Troch, science director.

“You basically create the same conditions all over again, every three days.” This will go on for 10 years across three manmade hills, each peppered with more than 1,800 sensors to measure exactly where the water goes, down to the molecule.

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