As part of their "Month of Thinking Dangerously" series, in which they interview "experts" about various "dangerous" ideas, Big Think interviewed Stephen Hawking. Mr. Hawking is considered a Theoretical Physicist.
"It will be difficult enough to avoid disaster on planet Earth in the next hundred years, let alone the next thousand, or million. The human race shouldn't have all its eggs in one basket, or on one planet," says Stephen Hawking.
Watch Stephen Hawkings in the following Big Think interview clip to hear him in his own words. Following the Big Think clip, we will discuss whether space is habitable.
Stephen Hawking:
I believe that the long-term future of the human race must be in space. It will be difficult enough to avoid disaster on planet Earth in the next hundred years, let alone the next thousand, or million. The human race shouldn't have all its eggs in one basket, or on one planet. Let's hope we can avoid dropping the basket until we have spread the load.
I see great dangers for the human race. There have been a number of times in the past when its survival has been a question of touch and go. The Cuban missile crisis in 1963 was one of these. The frequency of such occasions is likely to increase in the future. We shall need great care and judgment to negotiate them all successfully. But I'm an optimist. If we can avoid disaster for the next two centuries, our species should be safe, as we spread into space.
If we are the only intelligent beings in the galaxy, we should make sure we survive and continue. But we are entering an increasingly dangerous period of our history. Our population and our use of the finite resources of planet Earth, are growing exponentially, along with our technical ability to change the environment for good or ill. But our genetic code still carries the selfish and aggressive instincts that were of survival advantage in the past. It will be difficult enough to avoid disaster in the next hundred years, let alone the next thousand or million. Our only chance of long term survival, is not to remain inward looking on planet Earth, but to spread out into space. We have made remarkable progress in the last hundred years. But if we want to continue beyond the next hundred years, our future is in space. That is why I'm in favor of manned, or should I say "personed," space flight.
Is life in space a real possibility? In order to answer this question, we must investigate what has been accomplished in the area of biosphere development.
"Biosphere 2" is a well known experimental complex (thanks to their public relations efforts) with a closed ecological system. Funded by Texas multimillionaire Edward P. Bass, Space Biospheres Ventures built an airlock-sealed habitat in Arizona, USA, initially stocked with over 3000 species (since nobody could predict which ones would survive as food chains evolved) - food producing and other plants, fish, trees, etc., and a crew of eight people. It is the largest closed ecological system ever built, at 2.3 acres - about 13,000 square meters. In Mission 1, the facility was closed and sealed, and the crew lived inside for two years from 1991 to 1993.
Biosphere was heavily instrumented for research, safety and operations management, with over 2000 points of data collection.
The 3000 species were separated into several different miniaturized biomes based on different earth ecosystems, land systems ranging from rain forest to desert, and marine systems ranging from marsh to coral reef. The diet was nutritious and diverse, utilizing over 80 crops along with goat's milk, eggs and some animal meat, with average daily caloric intake of approximately 2200 calories, including 70 grams of protein and 32 grams of fat.
There were some small leaks in the facility, but air exchange was kept to less than 10% per year. In the second year, the oxygen level hit a low point (14%, as compared to 20% in earth's atmosphere) and carbon dioxide a high point in the winter (9.5 hours of sunshine) due to less sunlight plus unusual cloudiness due to an "El Nino" weather event in the region that year (the cloudiest winter in more than 50 years - worst case scenario bad luck!). The carbon dioxide level varied between 1000 parts per million (ppm) in June 1992 (14 hours sunshine) and 2700 ppm in December 1991, with sunny daily/nite fluctuations on summer days resulting in 600 to 800 ppm changes. (In the continuous sunshine of orbit, exchanging carbon dioxide and oxygen between plants and animals shouldn't be a problem at all, with mirror controls increasing either to any reasonable level. Of course, there's plenty of oxygen in the dirt of the Moon and asteroids, and plenty of carbon in asteroids, but it would be nice to have a naturally balanced system.)
After an initial shaking out of some species, the ecosystem reached a fairly stable overall equilibrium with careful human management. The facility produced 90% of the crew's dietary needs over this time. (With more sunshine in space, food self-sufficiency should be readily attainable.) Most of the other 10% came from foods grown in the facility before the crew arrived, and from seed stock. (There was also some fudging, as discussed in a moment.)
Many lessons were learned about managing a small closed ecological system in Mission 1, and there were proposed changes in the species stocking in preparation for a Mission 2. Facility sealing to give an air leakage of just 1% per year was anticipated for Mission 2.
As one of the live-in researchers wrote: "As we prepare to eventually test and deploy preliminary, small biological life-support systems in space, and then move on to biospheric systems constructed of space-available materials, we may feel constrained by the limitations and requirements which life systems impose. But we may also be surprised, as we have been in Biosphere 2, by the adaptability of nature and by its resourceful self-organization into viable systems. As we create mini-worlds for space exploration and habitation, the prospect beckons that we will create a profusion of new and beautiful worlds never before seen on Earth. And as these worlds mature in their unique metabolic linkages … we can expect that we and they will continue to adapt and evolve in response."
A good report entitled "Biosphere 2 and Its Lessons for Long-Duration Space Habitats" was given at the SSI/AIAA Princeton conference in 1993. A vast bibliography of papers and books on "biospherics" is given at the home site of the managers who worked on this initial Biosphere.
A picture of Biosphere 2 is now on the internet.
However, a Mission 2 will apparently never happen in Biosphere 2, and indeed, Biosphere 2 has been retreating into oblivion as regards application to space habitats. Its financier has apparently reacted to criticism by not only changing the management but also changed the purpose of Biosphere 2 along the lines of interest of a new joint venture.
What happened?
During the course of Mission 1, the management of Biosphere 2 installed a carbon dioxide scrubber and also provided some supplies from the outside without reporting these actions to outsiders observers. To make matters worse, two of the managers took a defensive stance when criticisms were raised regarding the degree of self-sufficiency and the lofty claims of the project. (We're not sure whether it was dishonest or misleading actions.)
It would have been understandable (though a little bit disappointing) if the managers had reported unforeseen problems with Mission 1 and reported the measures they had decided to take. If they had been open, the project would have been seen as a great learning experience nevertheless, though not a complete success. Surely, some journalists and egotistical scientists would still have taken shots and sought high profile publicity by criticisms in any case, but it would not have been such sensational criticism, and there would have been due respect by the low key portion of the scientific research community which truly matters. There almost certainly would have been a Mission 2 based on the lessons of Mission 1.
Instead, the press had enough justification to engage in a feeding frenzy. Understand that before Mission 1, the press built up Biosphere 2 as one of the greatest ongoing projects on Earth, e.g., Discover magazine called it "the most exciting scientific project undertaken in the U.S. since President Kennedy launched us toward the Moon", and Phil Donahue did a live on-site broadcast, calling it "one of the most ambitious man-made projects ever". Once something becomes that famous, it attracts egotistical journalists and upwardly mobile scientists who rely on criticisms of others to raise themselves up - the bigger the target, the greater the benefit to one's self if they can land a valid punch. Before long, practically nobody would defend the elements of Biosphere 2 that were worth appreciating, and the stories focused only on its misgivings. Indeed, the focus quickly migrated to sensational, juicy personal matters, e.g., characterizing the group as a cult. In terms of sociopolitical trends, Biosphere 2 had gone from one extreme to the other in the eyes of the press.
When the above issues were raised, the scientific merit of the project also came under a media microscope. While the project collected valuable scientific data and practical experience, it was never set up as a proper scientific laboratory according to certain standards. (Indeed, it's difficult to take on such a large and complex task as Biosphere 2 with a near-term schedule and stick to the stringent scientific standards of academia and the slow, one step at a time process of exact science.) When the project's openness and honesty was called into question, the value as well as the integrity of the scientific data was also called into question by some elements of the popular science media as well as hard science media analysts.
In order to deal with this overwhelming pressure and dramatic loss of face, the financier of Space Biospheres Ventures fired the management of Mission 1 and replaced it with highly respected scientists of the most impeccable credentials. After almost two years, a different project had taken a life of its own, albeit much drier, less ambitious and lower profile. The later project benefitted from the publicity and support of the former project, but without the corresponding ambition and risk.
According to a press release by Columbia University, Biosphere 2 started working closely with Columbia University's Lamont-Doherty Earth Observatory in 1994, one of the world's leading institutions on studying Earth's complex systems, in a joint venture named Biosphere 2 Science Consortium, which included scientists from many leading universities and institutions around the world. For example, scientists from Harvard, Yale, Stanford and Australian National universities, the Smithsonian Institution and others have been working as part of the consortium on issues ranging from biogeochemistry to ecology. (I don't know where the income for all this came from, but they are apparently pulling it in.)
In late 1995, Biosphere's entrepreneurial backer, Edward P. Bass, announced a 5 year agreement to extend this joint venture whereby Lamont-Doherty manages and directs the Biosphere's scientific, educational, and visitors center operations, and will share rights to the commercial application of all new technologies and inventions.
The purpose of the facility is no longer "habitats for space", but is for studying earth's ecosystems. There will be no more sealed missions of people inside the habitat, and the work does not look directly applicable to space habitats any more. Space Biosphere Ventures is out, and Biosphere 2 Science Consortium is in.
RESOURCES:
The Human Experiment: Two Years and Twenty Minutes Inside Biosphere 2
A Briefer History of Time
Life Under Glass: The Inside Story of Biosphere 2
The Universe in a Nutshell
Me and the Biospheres: A Memoir by the Inventor of Biosphere 2
The Grand Design
Dreaming the Biosphere: The Theater of All Possibilities
The Illustrated Brief History of Time, Updated and Expanded Edition
Eating in: From the Field to the Kitchen in Biosphere 2
The Theory Of Everything
The Human Experiment: Two Years and Twenty Minutes Inside Biosphere 2
Stephen Hawking and the Theory of Everything
The Biosphere, 2nd Edition
George's Secret Key to the Universe
Biosphere 2, Oracle, Arizona Photographic Poster Print by Eddie Brady, 9x12
God Created the Integers: The Mathematical Breakthroughs that Changed History
The Illustrated A Brief History of Time / The Universe in a Nutshell - Two Books in One
The Illustrated On the Shoulders of Giants: The Great Works of Physics and Astronomy
On The Shoulders Of Giants
A Brief History of Time: From the Big Bang to Black Holes
Stephen Hawking: A Biography
Stephen Hawking's Universe: The Cosmos Explained
Stephen Hawking's Universe
The Nature of Space and Time: (New in Paper) (Princeton Science Library)
A Brief History of Time and the Universe in a Nutshell
Black Holes and Baby Universes and Other Essays
Illustrated Theory of Everything: The Origin and Fate of the Universe
Stephen Hawking's Universe
The Black Hole War: My Battle with Stephen Hawking to Make the World Safe for Quantum Mechanics