Whatever Happened to Biosphere 2?

Many of us may recall captivating images of an enormous glass and steel superstructure making the headlines in the 90’s, along with the tale of eight human test subjects who would enter, live, and remain in this special environment completely sealed off from the outside world. At the time with phrases like ‘test facility for possible future lunar and planetary habitation’ associated with it, the Biosphere project re-inspired imaginations the world over and sustained the hopes of those ambitious for mankind to further explore and someday inhabit new destinations in space.

Planet Earth’s largest closed ecological system in Arizona, the Biosphere 2 complex.

Planet Earth’s largest closed ecological system in Arizona, the Biosphere 2 complex. (Image credit: Johndedios via Wikimedia Commons)


So what about the Biosphere today? Does it still exist, and if so how has the project fared with the passing of time? Also what were the results of the human experiments and what do they indicate for the feasibility of future lunar/planetary habitation? These are some of the questions we will seek answers to as we re-examine the Biosphere, 20 years on.

With Biosphere-like space structures featuring in sci-fi films such as Sunshine and even as far back as 1979’s The Black Hole, the essential concept of Earth’s oxygen-rich life-sustaining atmosphere being recreated in space, vegetation beneath glass, has been around for a very long time. Perhaps the Biosphere’s landmark achievement, in terms of potential space technology, was that it mysteriously fused this myth with reality and on a spectacularly lavish scale.

Named after Earth’s biosphere, the only known life system in space (Biosphere 1), the world’s largest artificially closed system –‘Biosphere 2’ was constructed from 1987 at the foot of the St. Catalina Mountains in Arizona. A feat of engineering in itself, the 3.14 acre glass building and its five ‘biomes’ were completed by Space Biosphere Ventures in 1991. On 16 June 1994 a crew of eight, four men and four women (including the two authors of the project), were sent to live inside Biosphere 2. With no comings, goings, or contact permitted between the ‘Biospherians’ and the outside world for a period of two years, these sole human occupants were to test if life within an artificial recontruction of Earth’s life-supporting environment could be sustained.

Some of the most informative findings of the Arizonian ICE (Isolated Confined Environment) experiment proved to be in regards to the actual effect of the confinement on the mission crew, their working relationships with one another and the direct influence these had on the fulfillment of the overall mission objectives. The Biosphere 2 two-year experiment proved beyond any doubt that the interpersonal relations affects a crew’s productivity. These lessons are of value as in turn, productivity would be of paramount importance when and where a Biosphere 2-type crew would be mankind’s sole representatives as lunar/planetary explorers and on whom potentially crucial scientific discoveries in space may depend.

As a kind of ‘Noah’s Ark’ for plants, animals, and humans, Biosphere 2 sought to recreate the communities of Earth’s main ecosystem districts. These various ‘biomes’ included an agricultural area, a human working and living space, a million-gallon ocean and coral reef, a fog desert, savanna grassland, mangrove swamp, and tropical rainforest, all of which were housed under the manmade structure’s glass and steel canopy. A great facet of these artificial biomes was the unique opportunity they afforded to study climate hypotheticals along with the multiple effects, large and small, expected and unpredicted that these changes would have on the species within. Since twenty minutes of unregulated temperature on a sunny day could permanently damage plants beneath the biosphere’s glass, a natural gas primary generator and a diesel fuel back-up generator in the five-arch Energy Centre could within minutes provide power to maintain control of the biome environments. To this day, 26 air handler units in the basement or ‘Technosphere’ have the ability to heat and cool air and create condensate water for Biosphere 2’s ocean, rain and fog atmospheres.


glass and steel

A closer look at the structure whose project Discover Magazine once described as “…the most exciting venture to be undertaken in the US since President Kennedy launched us toward the Moon.” The building’s architects also won the top ‘Special Award’ in the Pacific Rim 1992 Gold Nugget Award Contest for the Commercial/Industrial Public/Private Special Use Facility category.  (image credit: Daderot via Wikimedia Commons)

With no comings or goings permitted during the Biospherians’ two-year confinement, the experiment among other things set out to test if living inside an artificial reconstruction of Earth’s life-supporting environment in the long-term would be possible. With the Sun’s heat frequently causing Biosphere 2’s contained volume of 161 000 cubic metres of atmosphere to expand, the formation of cracks started to indicate some structural stress on the building’s exterior. The solution for this problem was provided with an additional set of chambers or ‘lungs’ which allowed for the overflow and extraction of air, yet  without compromising the enclosure’s integrity.  Although ‘materially closed’ to the outside world, energy and information (electricity, computer data, video etc.) could come and go.Biosphere 2 supported and was operated by the eight crew members until their confinement was completed on 26 September 1993. The Biosphere 2 contained over 3000 documented species of plants and animals across its five biomes.

This once-flourishing agricultural biome provided the Biospherian’s with 80% of their nourishment for the two-year period, a figure recognised internationally as ground-breaking in terms of self-sustainability for a closed ecosystem

This once-flourishing agricultural biome provided the Biospherians with 80% of their nourishment for the two-year period, a figure recognised internationally as ground-breaking in terms of self-sustainability for a closed ecosystem. (Image credit:Daderot via Wikimedia Commons)


Not only did the prolonged Biosphere enclosure provide an excellent opportunity to study the processes of closed ecosystems and the complex interactions between species, but much was learned retrospectively about the social factors and the psychological effect on the mission and its crew. With the Biosphere and space missions crew structure based on the usually highly-effective maritime model, the two-year Arizonian desert experiment  made some interesting revelations. The project data suggested that a more flexible management style independent of interference from Mission Control and giving more autonomy to individual crew members in the execution of their duties could help reduce stress levels. Although the crew members’ personal commitment and belief in the Biosphere ideology was never in question, at some point during the confinement most of the crew said they had the feeling of “wanting to go somewhere”.

Also, three facilities the Biospherians were reported as having valued most highly during their ICE experiment were the private room/sleeping quarters allocated to each of them to which they could retreat, being able to talk to other crew who were simultaneously performing an ICE in Antarctica, and the electronic mail facility which enabled them to maintain some relationships outside of their Biospherian existence.

The crew’s living quarters and ‘lung’ beyond

The crew’s living quarters and ‘lung’ beyond (Image credit: DrStarbuck (Flickr) via Wikimedia Commons)


Despite the fact that each individual on the team had been carefully selected and thoroughly interviewed before being admitted to Biosphere 2, two main groups emerged from among the eight during the Biosphere’s closure. Essentially with differing views on the best mission strategy for the crew,  a correlation was observed identifying interpersonal relations being at their lowest ebb simultaneously with oxygen levels also dropping to their lowest point during the 24 months. With an unusually dark, overcast winter to blame for reduced plant and crop production, lowered oxygen and increased carbon dioxide levels in turn affected the crew’s otherwise improved health. Where the Biospherians’ reduced cholesterol and blood pressure had been a glowing tribute to the vitamin and mineral-rich diet along with the closed system lifestyle concept in general, the changing atmosphere within Biosphere 2 in equal measure demonstrated the fatigue, lack of motivation and hypoxia that could result from a disfunctional biosphere existence. More serious management problems during a second human confinement in 1994 heralded the experiment’s early cancellation and this brought the world’s longest closed system human confinement project to an end. During the period the oxygen dropped, the Biosphere 2 experiment demonstrated that a human crew could operate well between an oxygen level of 16%-19%.

The Biosphere’s beach, million-gallon ocean (containing a coral reef), and Savanna grassland beyond.

The Biosphere’s beach, million-gallon ocean (containing a coral reef) and savanna grassland beyond. (image credit: Phileco1 via Wikimedia Commons)


Often large-scale ventures that are the manifestations of a radical vision acquire their fair share of critics and objectors. The original Biosphere project in Oracle, US was no different. Many believed that human existence could simply not be supported within an artificially-closed environment, and others thought that it was wrong to try. However not only did it achieve the two year confinement goal for which the media blessed it with international fame, but Earth’s ‘second biosphere’ ultimately provided a harvest of useful scientific, biological, social, and psychological discoveries that could not have been attained any other way. In terms of the usefulness of the Biosphere 2 project for possible future deep-space colonisation NASA have seemed anxious to keep a finger in the Biosphere pie. Involved in the early international conferences that formed the foundational planning for Biosphere 2, and since the main human psychological findings from Biosphere 2 concur with those of other ICEs such as those in the Antarctic, NASA will most likely return to this specialised data in future when planning for deep space missions such as the requisite 8.5 month journey to Mars (interestingly two former Biospherians, Jane Poynter and Taber MacCallum, are key players in Inspiration Mars, Dennis Tito’s proposed crewed Mars fly-by). Even when oxygen levels were low and the Biospherians’ existence was less pleasant as a result, and although overruled on the issue by the Biosphere’s Mission Control, all crew members wanted the complex to remain sealed for the integrity of the closure experiment. This and the fact that despite some social stresses and frictions during the two-year ICE all crew members were unanimous in their stated desire above all, to see the artificial biosphere’s two-year test through to its conclusion is a tribute to the persistence of the human spirit and vision that has marked the Biosphere 2 venture since its birth.

Since the ICE missions of the ’90s, Biosphere 2 has been reinvented as an ‘open’ scientific research institute and under the management of the University of Arizona educational programs and walk-through tours are offered to the public. Or in its own words, Biosphere 2 exists today “To serve as a centre for research, outreach, teaching and life-long learning about Earth, its living systems, and its place in the Universe”.


(Article by Nick Parke, Education Support Officer)