It was the ultimate social-distancing experiment.

On September 26, 1991, four men and four women in dark-blue spacesuits waved goodbye to friends, families and a bank of television cameras as they stepped through an airtight door to embark on an unprecedented mission. In spite of their “Star Trek” styled uniforms, the eight adventurers did not blast off to outer space but sealed themselves off from the outside world for two years inside Biosphere 2—a three-acre, glass-and-steel terrarium in the Arizona desert.

“The future is here!” declared crew member Jane Poynter as she stepped inside the $150 million ecological laboratory and planetary commune prototype that featured 3,800 species of plants and animals and five miniature biomes—a rainforest, coral reef ocean, marsh, savanna and desert.

To test the human capacity for living in isolation in outer space, the eight “Biospherians” hoped to be entirely self-sufficient by growing their own food and recycling all air, water and waste. While they could communicate with the outside world by email, telephone and fax, for two years there would be no hugs with loved ones, no food deliveries, not even any toilet paper.

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The idea for Biosphere 2 (Earth being the first biosphere) emerged from an avant-garde theater and ecological commune known as the “Synergists” that originated in San Francisco in 1967. “What distinguished this group from other counterculture types is they identified as capitalists,” says Matt Wolf, director of “Spaceship Earth,” a 2020 documentary about Biosphere 2. “Their model was to create enterprises designed to be both economically and ecologically sustainable.”

The Synergists operated ecological projects from the tropical rainforest in Puerto Rico to the Australian outback and even built their own ship that they sailed around the world. They were led by charismatic polymath John Allen, a Harvard MBA and metallurgist who penned poems and short stories under the pseudonym Johnny Dolphin and who, according to a 1994 Arizona Daily Star article, was “described by those who’ve known him as both a visionary and an abusive mind-control guru.” Allen has repeatedly refuted the charges made by his critics and denied to the newspaper “all allegations concerning singular and authoritarian control over the Biosphere 2 experiment.”

Billionaire Edward Bass, the maverick son of an oil tycoon and a self-styled “ecopreneur,” was among those drawn to Allen after visiting his Synergia Ranch in New Mexico. With Allen’s vision and Bass’s money, the Synergists constructed Biosphere 2 north of Tucson.

Longtime commune member Mark Nelson was among the eight-person crew who entered Biosphere 2 in the fall of 1991. “There were moments of absolute bliss, and if you wanted privacy you could hide yourself in a number of biomes,” he says of his experience. The Biospherians celebrated Thanksgiving with a feast of chicken, baked squash and sweet potato pie and toasted the winter solstice with rice wine.

Wintertime cloud cover, however, contributed to crop failures and low oxygen levels that made the eco-explorers feel as if they were at an elevation of 14,000 feet. Hummingbirds and honeybees died while ant and cockroach populations exploded. The Biospherians lost significant amounts of weight as the long workdays, oxygen depletion and low-calorie diets made even climbing stairs a daunting challenge.

Those setbacks didn’t help group dynamics, which Nelson said was the most difficult part of life inside the bubble. Although Biospherians broke into factions, he says it didn’t impact their research. “What usually happens in small groups is subconsciously they start to sabotage their work and the overall mission,” Nelson says, “but that never happened because we all fell in love with Biosphere 2.”

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While scientists questioning the validity of Biosphere 2’s experiments cast stones at the glass house, the project’s public image also suffered from a lack of transparency. Two weeks after entering Biosphere 2, Poynter departed for surgery after severing a fingertip in a rice-threshing machine.

Months later, it was revealed that she brought along a duffel bag full of equipment upon her return. Then came revelations that a three-month supply of food had been stockpiled inside Biosphere 2 before the experiment began, that air was being pumped inside and that its doors had been regularly opened to bring in supplies such as seeds, vitamins and mouse traps.

With an endeavor so big, the Biospherians fully expected failures. “That’s why you do experiments—to learn what you don’t know,” Nelson says. However, the media tended to cover the enterprise like a survivalist reality show. “The theatricality drew a lot of eyeballs, but the nuance of what this group was trying to do with long-term visions was lost in the expectation that it was this human experiment in which eight people are locked in and nothing can go in and out,” Wolf says.

In spite of the challenges they faced, the eight Biospherians made it through their two years apart from the world. The next crew, however, would not.

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Weeks after the new seven-person crew entered Biosphere 2 on March 6, 1994, problems back in the first biosphere intruded on the project. With the enterprise’s finances floundering, Bass placed the company into receivership and named investment banker Steve Bannon, who would become a key advisor to Donald Trump’s 2016 presidential campaign, as the new CEO.

Bannon insisted on the removal of Allen and other senior managers. Fearing for the new crew’s safety, original Biospherians Abigail Alling and Mark Van Thillo broke into Biosphere 2 before dawn on April 4, 1994, to warn of Bannon’s involvement. “I considered the Biosphere to be in an emergency state,” Alling said. “I made a conscious decision to terminate the experiment.”

While the Biosphere 2 crew decided to stay, they vacated it five months later as the venture devolved into a flurry of lawsuits and countersuits. Bass donated the facility to the University of Arizona in 2011, and research on smaller projects continues.

“The reality of what the endeavor was all about got lost in the shuffle,” Nelson says. “This was to be the prototype for a space colony and to judge it by whether it worked for two years isn’t true to its purpose and trivializes the whole thing. Biosphere 2 is a 100-year project. We built it for the long-term investigation of fundamental processes underlying the earth experience.”