If you build it, scientists and the public will come. That's the hope researchers are holding on to as they work to revive a defunct artificial ocean in the middle of the Arizona desert.

The ocean belongs to Biosphere 2, the glass-walled structure near Tucson, Arizona, made famous by human experiments in the 1990s. Eight people sealed themselves inside the facility designed as a self-sustaining version of Earth. The two-year mission was supposed to approximate how people would have to live and work on a space colony. (Related: "1994: People Migrate to Biosphere 2.")

Biosphere 2's original 676,000-gallon (2,555,894-liter) ocean was designed as a coral reef reminiscent of the Caribbean. But over the years, most of the coral died