biodome experiment in arizona

October 4, 2021

Biosphere 2: The Once Infamous Live-In Terrarium Is Transforming Climate Research

Despite its controversial past, the quirky desert facility is becoming increasingly relevant as it turns 30

By Keridwen Cornelius

Biosphere 2’s living quarters and library, circa 1992.

Joseph Sohm Getty Images

ORACLE, Ariz.—Opening the door to a glass pyramid, a visitor steps from the arid heat of Arizona into a coastal fog desert that stretches toward a savanna. A Lilliputian ocean laps against a rocky shore. A passageway leads to a steamy rain forest where vine-necklaced trees tower 90 feet high. Here in Biosphere 2, the world’s largest controlled environment dedicated to climate research, scientists can tinker with scaled-down ecosystems by switching off sprinklers and cranking up the thermostat to learn about the effects of global warming out in the real world.

The facility has long been shadowed by its ill-fated 1991 maiden mission to establish an analogue of a self-sustaining colony on another planet. But after some retooling and successful, high-profile studies —including one that revealed warming oceans are killing corals—the giant terrarium (led by the University of Arizona since 2011) is finally living up to its potential as a site for novel and risky research.

In its half-acre rain forest, scientists are probing how tropical ecosystems might weather late-21st-century heat and drought. Soon researchers hope to experiment with radical coral reef restoration methods in the enclosure’s million-gallon ocean. And in March 2022 the operation will unveil a Mars analogue that reprises the original founders’ dream of mimicking a plant-filled habitat on a lifeless alien world. Biosphere 2 is effectively like a time machine that can preview a climate-altered Earth “by changing the concentrations of gases in the atmosphere to those that we think are going to exist in the future to see how the planet could fare,” says the facility’s current director Joaquin Ruiz.

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Past Struggles

Biosphere 2 launched 30 years ago, on September 26, 1991, when a crew of eight—including a physician, botanist and marine biologist—began a two-year residency inside this 3.14-acre terrarium. The structure, a prototype for an extraterrestrial habitat, was conceived by a counterculture theater troupe that partnered with businesspeople to form a company called Space Biosphere Ventures. It was intended to be a hermetically sealed ecosystem where several biomes, 3,000 species of plants and animals, and a farm would provide the “biospherians” with all the air, water and food they needed. “At the time, a lot of scientists said it literally could not be done, that the whole thing was going to turn into green slime,” says Jane Poynter, one of the original biospherians and founder of spaceflight company Space Perspective.

Biosphere 2 contains a mini ocean next to a savanna and a mangrove forest. Credit: Alamy

The enclosure did not ooze slime. But after a year, the oxygen had dwindled to dangerously low levels, the farm was not producing enough crops—and the crew was suffocating and hangry. To solve the problem, some members of Space Biosphere Ventures’ management team pumped oxygen into the building and used a CO 2 “scrubber” without disclosing their actions publicly. When the truth emerged, the mission lost credibility with scientists and was panned by the press. Some still consider this unfair. “It was absurd that the media portrayed it as a failure, because it completely missed the point that it was an experiment,” Poynter says, adding that the goal was to discover what problems arise in a human-made biosphere and to learn from those dilemmas. The failure, say several of Biosphere 2’s current staff, lay in the lack of transparency—not the lack of oxygen.

Scientists did, in fact, learn something important from what went wrong: the soil was too rich in organic matter, and its thriving bacteria gobbled up too much oxygen. At first, the researchers could not track down the excess carbon dioxide those microbes should have released as a byproduct of that oxygen consumption. Eventually they found it had chemically bonded with concrete in the building. “It was a light bulb moment,” says John Adams, Biosphere 2’s current deputy director. “They could trace, molecule by molecule, where [carbon] was going and where it was being stored in ways that they couldn’t outside” in the real world.

When Columbia University took over Biosphere 2 from 1996 to 2003, researchers realized that, inside this controlled mini world, they could tweak the CO 2 , heat and precipitation to predicted future levels and could measure the effects on varied biomes. “Quite a few people thought that this is an exquisite tool because you have a complicated system that you can completely close and risk damaging and learn how stressed systems behave,” says Klaus Lackner, director of the Center for Negative Carbon Emissions at Arizona State University, who is not affiliated with Biosphere 2. “The challenge is: you have to make sure it’s actually reflecting a real system. I think one can walk that walk, and some of that [research] is being done now.”

Understanding the Future

Christiane Werner, an ecosystem physiologist at Germany’s University of Freiburg, used the facility’s rain forest to investigate how tropical plants and soil share nutrients to protect each other from climate change—and what happens when those support systems fail. Several recent studies have shown that deforestation and climate-related tree death are transforming rain forests such as the Amazon from carbon storage spaces into massive greenhouse gas emitters. Werner’s goal is to find what causes these tipping points. Doing so could help researchers make better climate predictions and develop more effective reforestation techniques.

Werner’s team released traceable forms of carbon and hydrogen into the glass-domed rain forest, then turned off the sprinklers to induce a 9.5-week “drought” and tracked where the elements traveled. “That has never been done before,” she says, “and Biosphere 2 is the one place on Earth where you can do such an experiment because you have a fully grown forest you can manipulate.” In the Amazon, it would of course have been impossible to conjure a two-month dry spell, and the chemical tracers could have escaped anywhere, she notes.

The soon to be published results are being kept under wraps, but Werner says the main takeaway was the diverse ways various plant species coped with the stress. “Because they have different functional responses, it buffers the whole forest,” she explains, adding that biodiversity is therefore key to keeping forests stable in turbulent climatic times.

Other experimental results from Biosphere 2’s rain forest have been heartening. In

a 2020 study published in Nature Plants, Michigan State University ecologist Marielle Smith and her colleagues dialed up the temperature and found that the tropical flora were more resilient to high heat than many had anticipated.

At the facility’s mini ocean, researchers are partnering with microbial sciences company Seed Health to dose corals with probiotics to see if this can deter bleaching (which occurs when heat-stressed corals expel the symbiotic algae that help feed them). The scientists are also developing a program to experiment with “super corals” that are bioengineered to be resistant to heat and acidity. “If you’re in Miami or Hawaii, you can’t get permits to do that research because there’s a fear that genetically modified corals will get into nature,” says Chris Langdon, a University of Miami marine biologist who is on Biosphere 2’s science advisory committee. “With Biosphere 2 being in the middle of the desert, there would be absolutely no risk if anything escaped.”

Langdon is no stranger to Biosphere 2’s ocean. In the 1990s he conducted research there, revealing for the first time that ocean acidification causes corals to dissolve from a lack of calcium. He says the giant tank would also be a good place to test a leading idea to achieve negative carbon emissions: raising the ocean’s pH by adding dissolved rocks, giving the water a greater capacity to pull carbon dioxide out of the atmosphere.

Not all of Biosphere 2’s projects focus on climate. Its so-called Space Analog for the Moon and Mars (SAM), currently under construction, “is very much, at a scientific level and even a philosophical level, similar to the original Biosphere,” says SAM director Kai Staats. Unlike other space analogues around the world, SAM will be a hermetically sealed habitat. Its primary purpose will be to discover how to transition from mechanical methods of generating breathable air to a self-sustaining system where plants, fungi and people produce a precise balance of oxygen and carbon dioxide.

Visiting researchers will hydroponically grow fruits and vegetables in SAM’s greenhouse, which is painted and tinted to block the sun and mimic the dimmer daylight on Mars. They will also experiment with transforming regolith (crushed rocks that resemble lifeless Martian basalt) into fertile soil. This could have implications for reviving some of Earth’s degraded terrains.

And in light of the precarious status of Earth’s climate, Staats hopes the scientists who live in SAM will experience the kind of epiphany he says was described to him by Linda Leigh, one of the original biospherians. “She said that, in such a closed environment, you can’t help but be aware of every breath you take, every drink of water you consume and every morsel of food you eat because it doesn’t go someplace where you never see it again,” he says. “It comes right back to you.”

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Take a trip to the tropics with our mangroves at Biosphere 2. This system allows us to look closely at two key types of wetlands and put plans to action for restoring these systems in the wild.

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When Biosphere 2 Became a Grand Experiment in Self‑Isolation

By: Christopher Klein

Published: May 12, 2020

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.

READ MORE:  Who Invented Toilet Paper—and What Came Before 

A Countercultural Commune Launched Biosphere 2

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.”

READ MORE:  1960s: Counterculture and Civil Rights Movement

Lack of Transparency Plagued the Project

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.

WATCH: The Untold Story of the 90s  on HISTORY Vault

Biosphere 2 Management Turned to Steve Bannon

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.” 

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8 men and women once sealed themselves inside this enormous fake Mars colony for 2 years. Here's what it's like today.

• Biosphere 2 was a highly ambitious experiment to simulate a self-sustaining Mars colony in the Arizona desert.
• Eight men and women locked themselves inside for 2 years and experienced one incredible challenge after another.
• Though the experiment is often described as a failure, Biosphere 2's participants disagree. They say it generated science that has only grown in value as NASA and Elon Musk, the founder of SpaceX, push to populate Mars .

A decade before Elon Musk founded  SpaceX  or spoke publicly about colonizing Mars , a different billionaire captivated the world with Biosphere 2.

Ed Bass, an oil tycoon, spent about $250 million to build and operate the facility as a proof-of-concept for a permanent, self-sustaining habitat on Mars. Four men and four women sealed themselves inside the airtight space in September 1991 and emerged two years later.

What followed was a spectacular and controversial story of human endurance , which is chronicled in a new documentary called "Spaceship Earth." The film debuts Friday on a handful of independent streaming   sites .

Built into a hillside of the Arizona desert during the early 1990s, the 3.14-acre Biosphere 2 complex remains a functional marvel of engineering. Business Insider visited the facility in April 2018 to investigate  the many challenges that early Martian colonists could face.

Here's what the high-tech complex of bubble buildings looks like today.

Biosphere 2 is nestled in the foothills of the Santa Catalina Mountains in Oracle, Arizona. The area is part of the Sonoran Desert — an arid, unforgiving, and eerily Mars-like region that stretches from western Mexico into the US Southwest.

Source: Biosphere 2 , Business Insider

A roughly 80-foot-tall glass pyramid poking out of the hillside greets visitors.

Source: Biogeosciences , Business Insider

Farther west in the sprawling 40-acre campus are other futuristic structures.

Source: " The Human Experiment ," Business Insider

The architect Peter Pearce created Biosphere 2's space-age frame out of 77,000 steel struts and 6,600 silicon-lined glass panes to trap air inside. It can even withstand orange-size hail, which pummels Arizona about once every century.

The first crew of Biosphere 2 walked through a modified submarine bulkhead on September 26, 1991, and sealed the airlock behind them. They wouldn't leave as a group for two years. That entryway is where tours begin today.

Source: Business Insider

Business Insider's tour guide was John Adams, the facility's deputy director. Adams has worked there since the mid-1990s and is an expert on Biosphere 2's complex systems, science, and history.

"It really showed us how little we truly understand Earth systems and how infinitely complex they are," Adams said of the first Biosphere 2 experiment. "There were a lot of people who said, 'You bottle this up, you close it up, it's just going to turn into a big ball of slime.'"

It didn't, and the eight crew members emerged alive — though they wound up needing some outside assistance.

When the first crew of "biospherians" settled inside the complex, it trapped 7.2 million cubic feet of air. All of its leaks added up to the equivalent of a thumb-size hole.

Source: " The Human Experiment ," Biosphere 2 , Business Insider

Though the facility was once a privately funded experiment in human survival, the University of Arizona bought it in 2011. It's now a scientific research facility, conference center, and tourist attraction.

Biosphere 2 has seen about 3 million tourists and 500,000 students since 1991. The site also contains a village where visiting researchers can stay. It's quiet out there in the desert, save for the wailing of coyotes at dusk.

Inside Biosphere 2, five "wilderness" zones — rainforest, ocean, savanna, marsh, and desert — emulated Earth's ecosystems. They helped scrub carbon dioxide from the air and generated oxygen. The crew lived in a connected habitat and farmed crops in an agriculture zone that's now called the hill slope.

In that intensive agriculture zone, shown here in 1993, crew members spent most of their 12-hour days toiling in the fields and animal pens to harvest enough calories.

The kitchen was hallowed ground. Biospherians ate only what they could grow — mostly sweet potatoes and beans. It took four months to harvest enough ingredients to cook a pizza. Animals had to be raised and slaughtered to get meat. Coffee was a twice-monthly luxury.

Biospherians kept detailed records of seeds, plants, food, and animals. About 20% of species inside — mostly insects that were out-competed by cockroaches and crazy ants — went extinct during the first two-year experiment. Today, a small fraction of the original species survives.

Crops no longer grow in the agriculture zone. Instead, the University of Arizona gutted and renovated it into a multimillion-dollar experiment called the Landscape Evolution Observatory (LEO).

LEO uses 90-foot-long bins of crushed volcanic rock to study how microbes transform inhospitable grit into environments where plants can take root.

The goal is to understand how climate change will transform formerly arid regions as they're doused with rain from new weather patterns. Hundreds of sensors and sampling tubes embedded in the bins give scientists a 3D view of the evolving soil. The work may one day come in handy for Martian farmers.

The most iconic areas of Biosphere 2, however, are its wilderness biomes. The air still smells of wet soil and plants, and though it's no longer sealed, it is noticeably more humid in here.

The "ocean" holds about 660,000 gallons of saltwater and undulates with the help of a large wave generator.

The ocean, one of the largest contained saltwater research facilities in the world, is being renovated to study coral bleaching, a scary consequence of climate change.

Source: Biosphere 2 , Business Insider ( 1 , 2 )

Next to the ocean — through a sealed door on a cliff — is the rainforest biome.

It's a thick, steamy jungle choked with tropical vines and trees.

Visitors aren't typically allowed into the rainforest area beyond a viewing point, but Adams escorted us around.

Biospherians treasured the bananas it grew for them. The sweet fruit was so versatile and prized in meal-making — and snacking — that it had to be locked in a room while it ripened (so no one stole it).

Many of the crew members sought out the rainforest's diverse ecosystems and soothing waterfalls for an escape. Today, it's an active research facility used to study tropical drought due to climate change, as well as the cornucopia of compounds emitted by plants.

After a trek through the rainforest, Adams walked us through the savanna, which connects the ocean, rainforest, marsh, and desert biomes.

This story was originally published in May 2020.

Plants of all shapes and sizes fill the savanna. During the first experiment, it also harbored a troop of four galagos, or nocturnal bush babies, that served as primate companions to the biospherians.

The desert biome at the end of the savanna encapsulates the environment that's right outside.

Biospherians spent a lot of time weeding the region, since winter condensation on the roof dripped into the soil, growing plants that should have been dormant.

Source: " The Human Experiment, " Business Insider

The complex's steel struts not only support the facility's glass panes, Adams explained, but also serve as a way to scale the walls for harvesting, measurement, cleaning, repairs and more. For fun, some biospherians even climbed to the ceiling and dove into Biosphere 2's ocean.

Today, a few biospherian living quarters are roped-off museum exhibits showcasing some belongings of the crew members of second mission's crew. (Because of financial and legal issues, it lasted only seven months, in 1994.)

In their spare time, some biospherians created art.

A small science museum set up in Biosphere 2's former control room shows off a prototype for establishing a self-sustaining base on the moon or Mars.

That concept, called the Prototype Lunar Greenhouse, consists of sealed tubes intended to supply 100% of the oxygen and 50% of the food a person needs in space.

The tubes are designed to pop out and assemble within 10 minutes.

A central module could deploy a dozen greenhouse tubes to keep a small crew alive for two years. This technology would, in theory, buy crucial time for astronauts to establish a permanent settlement on the moon or Mars. But NASA's funding for the project recently ran dry.

Around the corner from the museum is a staircase leading to the habitat's towering library.

The library offered biospherians a refuge from the cameras of a never-ending stream of tourists and press. This area, which still has the original and distinctive purple carpeting, is now off-limits to visitors.

It's a beautiful space with a skylit dome ...

... and a glass floor.

Underneath Biosphere 2 is secret underworld of vital human machinery: the Technosphere.

The Technosphere is a maze of pipes, tubes, conduits, pumps, sprinklers, transformers, air handlers, and other parts required to keep air, water, and electricity flowing through the complex.

As biospherians would discover, concrete that lined the facility's base was soaking up carbon dioxide. Soil microbes were gobbling up oxygen, turning it into carbon dioxide, and trapping it in the concrete — away from plants that could turn it back into oxygen.

Source: " The Human Experiment ," New York Times , Business Insider

This led oxygen levels to drop to the equivalent of the peak of a 15,000-foot mountain. To fix the problem, biospherians tried to collect every scrap of organic matter, dry it out in the Technosphere, and halt its decay.

But the design flaw proved too great. Mission managers eventually injected 14 metric tons of liquid oxygen into Biosphere 2 to make up for the chemically trapped gas.

That procedure was performed in one of two domed buildings called "lungs," which helped balance Biosphere 2's air pressure and prevent leaks. Without them, air that warmed during the day would have expanded and blown out panes of glass, ruining the experiment.

The lungs are remarkable feats of engineering. A giant weight suspended on an airtight membrane moves up as the facility's air warms and expands during the day, and drops when it cools and contracts at night. And if there is a small leak, the weight pushes air out (rather than sucks it in). A fan above the weight helps it move up and down.

"The membranes rose or fell simply in response to the state of expansion or contraction of the whole volume of air within Biosphere 2," Mark Nelson, who conceived of and made the overall design for the lungs, told Business Insider in an email. "Typically, that would be around 20 feet of vertical movement by both lungs every day."

To show how the lungs work, Adams opened a nearby airlock. The lung's weight immediately descended, forcing a blast of air through the unsealed door.

With my tour complete, I exited through the gift shop. On display was a book by Jane Poynter, one of the original crew members.

The book is one of the most detailed and candid accounts of Biosphere 2's genesis, construction, goals, and problems.

It's also an insider's account of a plethora of human and scientific controversies that haunt the project's reputation to this day — including a remarkable story involving sabotage, federal agents, and Steve Bannon, the former White House chief strategist.

Poynter eventually married Taber MacCallum, a fellow biospherian. "It was an incredibly audacious and, in so many ways, incredibly successful attempt at building a prototype space base," Poynter said of Biosphere 2.

Together, the couple started a high-altitude-balloon company called World View .

Some scientists today view the experiment with skepticism and describe its founding staff as "cultish," a description Poynter vehemently rejects. Barring a few design flaws, she said, Biosphere 2 showed that people could survive for years without much — if any — outside help.

Getting to Mars is the easy part — the success or failure of a colony will depend on its resiliency and life-support systems. Elon Musk is targeting a first SpaceX crewed mission later in the 2020s, but it remains to be seen how anyone would survive long-term.

"First we need to understand Earth's systems — we need to understand how we're going thrive here on Earth," Adams said. "We have not figured this out yet."

Sources: Business Insider ( 1 , 2 , 3 )

This story was originally published on May 1, 2018. It has been updated with new information.

• Main content

Biosphere 2: Explore the habitat's history and mystery in these amazing photos

Almost 30 years ago, eight researchers entered a glass-walled recreation of Earth's collective ecosystems out in the Arizona desert and didn't emerge for two years as part of a radical experiment.

In these striking images from the original experiment, which began in 1991, you can explore the facility known as Biosphere 2 (so named because the researchers considered planet Earth to be "Biosphere 1"). To dive even deeper down this rabbit hole, check out " Spaceship Earth ," a new documentary premiering on digital platforms and on the streaming platform Hulu May 8. 

These images, taken from archival footage from the original Biosphere 2 mission and shown in the new documentary, help to tell the true story behind this unique experiment.

Video: 'Spaceship Earth' tells story of 8 'visionaries' in Biosphere 2 - Trailer Related: 20 sci-fi movies and TV shows to binge watch on Netflix right now

Biosphere 2 was built from 1987 to 1991 in Oracle, Arizona. In 1984 the site was purchased by Space Biospheres Ventures and, in 1991, the first Biosphere 2 crew quarantine mission began. While it had some significant issues (a crew member had to once leave to go to the hospital, carbon dioxide levels were reaching unsafe levels and food was in short supply), the crew was able to complete their two-year stint in the odd, "bubble" environment. 

However, the second mission folded mid-way through its duration in 1994 and the facility changed ownership and it was shifted to more traditional research. There are no longer sealed, crewed missions like this in the habitat, but the facility is currently used as a large-scale laboratory by scientists at the University of Arizona.

Review: 'Spaceship Earth' is a radical ride through science, quarantine & more

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Inside Biosphere 2

Researchers originally built Biosphere 2 with the intention to create and study an artificial, self-sustaining biosphere, or the sum of all ecosystems that support life on Earth. The researchers wanted to explore and test whether they could recreate such a diverse and delicately balanced system in a closed environment. By living in it, they took this research a step further and tested whether the enclosure could support human life. 

"The main objective of the experiment was to determine if an artificial biosphere could operate, increasing storages of energy and biomass, preserving a high level of biodiversity and biomes, stabilizing its waters, soils and atmosphere," Biosphere 2 inventor and research director John Allen and original Biosphere 2 crew member and ecologist Mark Nelson said in a paper they published on the experiment in 1997 . They also wanted to know if the biosphere could provide "a healthy and creative life for humans working as naturalists, ecosystem scientists, and technicians," the researchers added. 

The habitat, with its striking, futuristic architecture, houses a number of human-created biomes including a rainforest, coral reef, ocean and more. The "biospherians," who made up the crews who lived quarantined in the facility, even had livestock that lived as part of this unique, enclosed system. 

Where things went wrong

The true story behind these quarantined missions in the 90s, which "Spaceship Earth" dives into, is as close to science fiction as reality gets. 

While the first group of biospherians were able to finish their two-year quarantined mission, the problems that arose in the habitat garnered such negative media attention that the second crewed mission was shut down halfway through its intended duration.

In the biosphere, interpersonal issues and tensions rose alongside issues with the biomes themselves. In the first mission, food shortages and a lack of oxygen required oxygen to be pumped in and the media took this as a serious failure of the experiment. But, while the second mission was able to correct some of the issues that arose with the first mission, Space Biosphere Ventures, the company behind the experiment, was dissolved, the facility changed ownership and the mission was cut short. Amidst this turmoil, Allen, along with other executive team leaders, was pushed to resign from the project following public scrutiny about his methods. 

Although the second mission ended early, these crewed missions were not failures. The team behind Biosphere 2 intended for these quarantined missions to be focused on research and development, and the biospherians were still able to collect an incredible wealth of data from their experiments and learn and explore. So, despite the unintended early ending, the mission still resulted in exciting exploration.  

Still, despite the original intent of the biospherians to simply explore and conduct unique research, the Biosphere 2 enclosure's sci-fi-esque look, the second mission's abrupt end and Allen's public perception have created some negative public perceptions of the project. "Spaceship Earth" intends to set the record straight with what actually went on inside the habitat.

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Chelsea “Foxanne” Gohd joined  Space.com in 2018 and is now a Senior Writer, writing about everything from climate change to planetary science and human spaceflight in both articles and on-camera in videos. With a degree in Public Health and biological sciences, Chelsea has written and worked for institutions including the American Museum of Natural History, Scientific American, Discover Magazine Blog, Astronomy Magazine and Live Science. When not writing, editing or filming something space-y, Chelsea "Foxanne" Gohd is writing music and performing as Foxanne, even launching a song to space in 2021 with Inspiration4. You can follow her on Twitter  @chelsea_gohd and @foxannemusic .

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The Lost History of One of the World’s Strangest Science Experiments

The hummingbirds were dying. Cockroaches were everywhere. And then Steve Bannon showed up.

By Carl Zimmer

Mr. Zimmer is a science columnist for The New York Times.

Before dawn on April 4, 1994 , Abigail Alling and Mark Van Thillo slipped across the foothills of Arizona’s Santa Catalina Mountains. They made their way to a looming monument of geodesic domes and pyramids known as Biosphere 2. The three-acre complex contained a miniature rain forest, a mangrove, a desert and a coral reef — along with seven people who had been sealed inside for a month.

Ms. Alling and Mr. Van Thillo had recently emerged from a two-year stay in Biosphere 2. Later, after they were arrested, they told reporters that they feared for the safety of the people inside. They were determined to bring the mission to an end .

They pulled open five of Biosphere 2’s doors and broke their seals. As outdoor air rushed in, they made their way to the ventilation system, where they smashed some glass panels.

That break-in effectively marked the end of one of the strangest experiments in the history of science. No one had ever built a sealed ecological world as big as Biosphere 2, and no one had ever survived so long inside one. The project would later be dismissed as a folly and a waste of effort. And yet, 25 years on, it’s an experiment worth rediscovering. Biosphere 2 might have some lessons to offer about managing Biosphere 1 — our planet.

The idea for Biosphere 2 emerged on a New Mexico ranch in the early 1970s. The residents of Synergia Ranch — who split their time between experimental theater, farming and furniture-making — saw themselves as picking up the pieces from the wreckage of civilization. “ Western civilization isn’t simply dying ,” the co-founder, John Allen, once said. “It’s dead. We are probing into its ruins to take whatever is useful for the building of the new civilization to replace it.”

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SUBMIT A STORY IDEA

Becoming a multiplanetary species: Crew completes first mission in pressurized habitat at Biosphere 2

Cassandra Klos, mission commander (left) is greeted by Linda Leigh (right), one of the original eight Biospherians, as the door is opened on the Space Analog for the Moon and Mars.

Chris Richards/University of Arizona

On April 27, a four-person crew sealed themselves in an air-tight, pressurized habitat on the grounds of the University of Arizona's Biosphere 2 , where eight people conducted a similar experiment more than 30 years earlier.

The Space Analog for the Moon and Mars , or SAM , habitat was created to allow people to experience what it might be like to live on the surface of another celestial body.

On May 2, six days after the first crew members entered the habitat, a crowd gathered to watch them emerge. As valves were released to decompress the habitat, it began to hiss, and a hush fell over the crowd. Minutes later, the pressure inside the habitat matched the outdoors, prompting Linda Leigh – one of the original eight people to live in Biosphere 2 for two years – to turn a red lever and swing open the habitat's airlock hatch.

The crew members spilled out with smiles on their faces and applause in their ears, marking the completion of SAM's first successful mission, Inclusion I .

"It's been a whirlwind, but a good one," said Inclusion I mission commander Cassandra Klos. "I'm so proud of everything we've accomplished together. We are a family and very appreciative to be the very first mission."

A habitat like no other

Kai Staats , director of research for SAM at Biosphere 2, spearheaded the habitat's design and construction with support from Tech Launch Arizona , Research Innovation and Impact 's Technology and Research Initiative Fund , the Controlled Environment Agriculture Center , Paragon Space Development Corporation and NASA.

Staats and his team created SAM to serve as an experimental prototype of a fully enclosed system that could be used to inform humans who might one day live and work in space. Preparation for living in space requires testing the feasibility of mechanical and plant-based life support, learning to maintain food crops in a sealed greenhouse, studying the microbiome of a sealed environment, practicing using tools when conducting an extra-vehicular activity in a full pressure suit, further developing a high-fidelity computer model to help design future habitats, and much more.

"SAM is an analog, which is a place to practice before you do the real thing," Staats said. "You can think of a pool as an analog – a place where you practice swimming safely before entering the ocean. In that respect, this building is an analog for how we might live on the moon and Mars. We're practicing our techniques, procedures, technologies and even our interpersonal interactions before we eventually carry ourselves to another planetary body."

The 1,200-square-foot SAM habitat combines the Biosphere 2 prototype Test Module greenhouse built in 1987 with a workshop, kitchen, common area and sleeping quarters. The Test Module greenhouse includes a hydroponic system to grow food with controlled lighting, humidity, heating and cooling. The workshop provides tools and a place to repair or build equipment for research and mission projects.

About a dozen analog space habitats exist globally, Staats said, but no others are sealed and pressurized like SAM.

The exterior of SAM. The test module is on the left, and the kitchen is on the right. The Inclusion I crew and some of the SAM team members stand in the foreground prior to the start of the mission.

The first mission

Anyone can apply to use SAM to conduct their approved research projects. Inclusion I is the habitat's first mission.

"Each team member brought their own science and mission objectives to this facility," Staats said. Staats and his team also asked the crew to study and report on conditions in the habitat, such as carbon dioxide and oxygen levels and flow.

The crew consisted of Klos, a fine art photographer and curator who visually documented the mission; mission medical officer Eiman Jahangir, a cardiologist, scuba diver, space enthusiast and two-time NASA astronaut candidate finalist; mission engineer Bailey Burns, a Blue Origin aerospace systems engineer focused on environmental control and life support systems; and mission communications officer and accessibility officer Sheri Wells-Jensen, a linguist who teaches at Bowling Green State University in Ohio.

Burns focused on monitoring lung pressure, oxygen and carbon dioxide levels in the habitat. Wells-Jensen helped the team consider the accessibility of the habitat. Jahangir ensured that the team stayed healthy and tested stress mitigation strategies.

While sealed inside, the crew members' only means of communication with the outside world was via delayed email, to simulate the physical reality of being far from Earth. From outside, Staats' team also constantly monitored the pressure, carbon dioxide, oxygen, relative humidity and temperature of the habitat.

The kitchen and common area of SAM.

"The team had to learn how to manage the airflow to control carbon dioxide levels. Even their exercise, cooking and sleep patterns affected carbon dioxide levels," he said. "But at no point were they close to harmful levels."

The crew got creative with vegetarian rehydrated and freeze-dried ingredients to prepare meals that resembled those that would be available to lunar or Martian astronauts. They also dehydrated and stored their food scraps so future crews could feed them to mycelium – mushroom roots structures – that in turn produce protein-packed mushrooms.

In addition, Wells-Jensen, who is blind, took a simulated space walk through the habitat's prototype moon-Mars yard – a space filled with very fine basalt and rocks to mimic lunar and Martian surfaces.

"What makes this extraordinary is that she is blind and used a cane," Staats said. "This is quite likely the first time a blind person has maneuvered across simulated Martian terrain in a pressurized space suit while breathing air through an umbilical cord drawn from a pressurized habitat."

Since you can't hear anything outside while wearing a pressure suit, Wells-Jensen could only rely on her team to guide her through the yard by radio.

Wells-Jensen added braille to many of the surfaces inside SAM to guide future crew members who might also be blind.

"My objective was to look at the systems and policies in terms of what would make this a welcoming space for any astronaut regardless of their background or how their body is configured," she said after exiting SAM. "One-quarter of the Earth has some significant disability, and we can't leave them behind. We need everybody with us."

Lessons for space and for Earth

Managing resources in SAM offers lessons not only on how to successfully live on the moon and other planets, but also how to live more sustainably on Earth, say those involved in the project.

For example, Inclusion I was allotted 60 gallons of water for four people over six days.

"They had to be careful with consumption, recycle as much as they could, and engage in daily quality of water analysis as they experimented with filtration," Staats said.

By the mission's end, the crew had used only 40 gallons of water.

"Many of us take 40-gallon showers, let alone live with three companions for six days with that much water," Staats said.

How we will someday live on the moon or Mars is how we should be living on Earth today, the mission participants said.

"Living within your means and living sustainability is not suffering," Wells-Jensen said. "It doesn't hurt you to be a good steward of the resources we were given."

Coming full circle

The Test Module greenhouse portion of SAM was originally built as a prototype for Biosphere 2, a large glass-enclosed habitat designed for research and development of self-sustaining space-colonization technology. Two missions, between 1991 and 1994, sealed Biospherians inside to test the design. Leigh lived in the test module for three weeks in 1989, before her two-year stay in Biosphere 2 with seven others. For over 20 years, the Test Module went unused until Staats had the idea to repurpose it, years after the university assumed ownership of Biosphere 2 in 2011.

Kai Staats, SAM research director, tends to the hydroponics system in SAM's Test Module greenhouse. The Test Module was originally built in the late 1980s as a prototype for Biosphere 2.

In 2014, Staats was a member of a two-week mission at the Mars Desert Research Station in Utah, which has been run by the Mars Society since 2001.

"I learned a lot," he said. "But as an inventor and entrepreneur, it got my wheels turning, and I thought that I could build something even better – not in a competitive fashion but by using my passion to create an analog that was as close as possible to the real thing."

After years of proposals and fundraising, Staats assembled a team that started building SAM in January 2021.

"We were lucky enough to come across this facility, refurbish it and bring it into a new era of function," Staats said. "This brings us full circle."

Turning science fiction into science reality

Staats said he's often asked why we should spend our time planning to go to the moon and Mars when there are still significant issues on Earth.

"The answer is easy," he said. "We are a species that has been exploring since its birth. We're always looking on the horizon and saying, what's beyond?" As he sees it, we're destined to "become a multiplanetary species."

Arizona state Sen. David Gowen introduced a bill to the Arizona legislature that, if approved as written, would allocate $1.5 million dollars to SAM.

"Arizona has been a great portal to the space industry. This is another project that comes from this great state and university," Gowen said after the crew emerged from SAM. "We want to continue to develop it."

A work in progress

Staats' team will take the crew's feedback and continue to improve upon SAM. The day after the crew exited, Staats and his team were installing a new pressure gauge and water filtration system, and making small modifications based on feedback, such as adding a place to hang flight suits and adding chairs in the Test Module. With each mission, they hope to get closer to a facility that could keep people alive elsewhere in the solar system.

This process is meticulous.

"Over the six days, every hour was accounted for," Staats said. "Everything from sampling water to monitoring pressure to oxygen, carbon dioxide and humidity. They also conducted a series of psychology studies around stress management and documented each day with photos and journaling. It's a complicated machine; it's a spaceship without rockets."

As SAM continues to grow, so will mission lengths. Eventually, missions will be months long. Until them, Staats and his team will prepare for the second SAM crew and mission, Inclusion II , which will run May 10-15.

Resources for the Media

Kai Staats Space Analog for the Moon and Mars [email protected]

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Biosphere 2

Biosphere 2 serves as a unique large-scale experimental apparatus housing seven model ecosystems with active research by teams of multidisciplinary scientists.