Habitats
Commission It First
We have already run phase one. It cost one man 150 million dollars of his own money, and it very nearly killed the people inside.
In heavy industrial construction, nothing gets handed to the client running. You build it, then you commission it — you run it empty, you run it loaded, you find every leak and every wrong valve and every place the drawing lied to you, and only then do you trust it with a life. Nobody skips that step on a gas plant. From what we can tell, nobody is planning to skip it before putting people on Mars, and that should worry us more than it does.
Phase one already happened
Most people who have heard of Biosphere 2 think of it as a punchline — the sealed dome in Arizona where the experiment “failed.” From what we have found, that is close to backward. Biosphere 2 was the closest thing humanity has attempted to phase one of exactly the commissioning process we mean, and it happened because one man decided to pay for it himself.
Ed Bass, a Fort Worth businessman, put up 150 million dollars of his own money to build Biosphere 2 between 1987 and 1991.1 No government funded it. No space agency ran it. A private citizen built a three-acre sealed world — rainforest, ocean, savanna, farm, and roughly 3,800 species — because he believed the question of whether people could live inside a closed system was worth answering before anyone tried it for real. He has kept backing the facility since; as recently as 2017 he gave another 30 million dollars to the University of Arizona to keep the research going.2 As far as we can find, he is still alive today. That is a man who deserves to be named every time this experiment comes up.
What phase one found
The first mission ran for two years, starting in 1991, with eight people sealed inside. It found the thing that only a real commissioning run finds: a failure nobody had designed for.
Oxygen inside the dome started at a normal 20.9 percent and fell steadily for sixteen months, down to 14.5 percent — equivalent to living above 13,000 feet.3 The crew developed fatigue, sleep apnea, and trouble concentrating. Doctors ended up injecting oxygen directly to keep people functioning. Nobody could find where the oxygen was going, because the plants and soil that were supposed to replace it were doing their job. What nobody had accounted for was the concrete. The structure’s own concrete was quietly absorbing carbon dioxide out of the air, faster than anyone expected, and locking the carbon away — which meant the oxygen the plants released was not being balanced by the CO2 the plants needed, and the whole cycle drifted.3
That is exactly the kind of failure a commissioning run exists to catch. You do not find “the concrete is eating your atmosphere” from a drawing. You find it by sealing the doors and living with the consequences for sixteen months. If that discovery had happened on Mars, with the nearest help eight months away, it would have been a death sentence instead of a lesson.
One system is not enough
There is a bigger lesson underneath the oxygen story, and it is one Earth itself teaches if you look at how our own atmosphere works. We assume plants make our oxygen. From what we have found, that is only half true. Roughly half of the oxygen in Earth’s air comes from ocean phytoplankton — drifting, mostly microscopic algae and photosynthetic bacteria — and the rest comes from land plants, with trees and rainforest specifically accounting for something closer to a quarter to thirty percent.4 Earth runs its oxygen supply on two independent systems that do not depend on each other. Biosphere 2 ran on one: soil and land plants. When that one system had a problem nobody predicted, there was no second system to carry the load.
A habitat that copies Earth’s redundancy, not just Earth’s chemistry, is a habitat that does not go quiet when one part of the cycle gets a surprise. That is not a small design note. It may be the single biggest argument for treating life support the way we treat any other critical system in construction: never on one leg.
Many rungs, not three
It would be easy to write this as a simple ladder — Earth, then the Moon, then Mars — and stop there. That is not the argument. There are many phases of commissioning ahead of us, not three. A geosynchronous orbit station is its own commissioning run, with its own failure modes that neither Earth nor the Moon will teach us. A Moon base is another. Multiple bases in multiple locations, each with different soil, different radiation, different gravity, are each their own test. Mars is not the second step after Earth. It may be the fifth or the tenth.
The advantage of doing this in order is the same advantage a commissioning engineer has on Earth: distance to help. A problem on a Moon base is three days from rescue. A problem on Mars is eight months from anything. We do not get to run the Biosphere-2-style surprise on Mars and simply fix it next season. We get to run it once.
Failure is not the word for what happened
Biosphere 2 is usually described as a failure, and it is worth saying plainly that this misreads what happened. The first mission was a shakedown run, and a shakedown run that finds a real problem before it kills anyone has done its job. The second mission ran shorter and cleaner, in part because the lessons from the first were applied.3 Every hard number in this article — the oxygen curve, the concrete, the pollinator collapse we wrote about in a companion piece, the wind that never blew — came out of that one facility, funded by one man, run on Earth, where a bad result cost money and morale instead of lives.
That is what commissioning is for. You do not run the test to prove the system works. You run it to find out how it fails, on ground where failing is survivable, before you bet a life on it somewhere it is not.
Where this leaves us
We are not proposing anything exotic. We are proposing the same discipline every industrial project already requires: build it, run it, break it on purpose or by accident, fix what breaks, and only then trust it with people, one rung at a time — Earth, orbit, the Moon, and whatever comes after, however many rungs that turns out to be — before Mars.
Biosphere 2 already gave us phase one, and it gave it to us for free, paid for out of one man’s own pocket. The only mistake left to make is deciding that phase one was the whole test.
If you worked on Biosphere 2, if you know Ed Bass’s more recent work, or if you think we have the order of phases wrong, we want to hear from you.
Come join us. Because we are Star Bound.
John LangEditor
Ideas in Star Bound are published open — take them, build them better. Our open proposal.
A note on where this comes from. I am not a metallurgist, a spacecraft engineer, or a degreed engineer of any kind. But I am a practical one, with more than forty years in heavy industrial construction: welding, millwright work, hydraulics, mining, and thirty-three years of electrical construction and commissioning on the North Slope of Alaska, in a place that punishes anything built wrong. Much of that time I have worked as a field engineer, which means I am the one standing in front of the equipment when the drawing turns out to be wrong, and the fix has to be made on the spot, with what is on hand, and has to work the first time. Anyone who has done that long enough learns that a lot of engineering gets corrected in the field by people with more experience than the people who drew it. That is the eye I bring to these subjects: not what should work on paper, but what actually gets built, and what breaks. The facts I take from other people are footnoted so you can check them and read further. The ideas built on top of those facts are my own, and I would rather see them knocked down by somebody who knows better than left standing because nobody looked.
Sources
- Wikipedia, “Biosphere 2” — https://en.wikipedia.org/wiki/Biosphere_2 ↩
- Tucson.com, “Billionaire Edward Bass donates $30 million to University of Arizona’s Biosphere 2” — https://tucson.com/news/local/billionaire-edward-bass-donates-30-million-to-university-of-arizonas-biosphere-2/article_392ed715-51fe-54c6-9d95-43a085c2e87b.html ↩
- Wikipedia, “Biosphere 2” (oxygen decline and concrete carbonation) — https://en.wikipedia.org/wiki/Biosphere_2 ↩
- National Geographic, “Source of Half Earth’s Oxygen Gets Little Credit” — https://www.nationalgeographic.com/science/article/source-of-half-earth-s-oxygen-gets-little-credit ↩
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- Life in the BarrelO’Neill gave us the barrel in 1976 and got very little of it wrong. What he did not finish was the inside — and the standard the inside has to meet isn’t twenty years. It’s forever.
- Worms: The Backbone of CivilizationWhy the first Martians will need a bucket of worms more than another rocket
- Send the Robots FirstWhy the road to Mars runs through the moon, and why the first lunar miners will never leave Earth
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- Cold, Vacuum, and a Hundred Thousand JointsWhat geosynchronous orbit does to the ten-inch panels in "A Thousand Garages," starting with the question every steel man asks first — and one thing that article got wrong.
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