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© CDO courtesy of the University of Arizona

How Living Inside Biosphere 2 Changed These Scientists' Lives

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© CDO courtesy of the University of Arizona

Taber MacCallum and Jane Poynter witnessed the most affecting solar eclipse of their lives in 1992. That's because as they watched the Sun disappear behind the Moon’s shadow, they were also watching their oxygen supplies slipping away.

At the time, they and their six teammates were sealed inside Biosphere 2, a 91-foot-tall, 3.14-acre experimental complex outside Tucson, Arizona. “We were all just glued to the monitors,” MacCallum recalls, “because you can see when the Sun was hidden away by the Moon, for that half hour period, the CO2 started going up. The oxygen started going down. You could see the actual, palpable effect.”

Without the Sun, the plants around them had stopped photosynthesizing and producing oxygen. Earth’s atmosphere is so huge that half an hour of this during a solar eclipse doesn’t have a noticeable effect. But inside an atmosphere 19 trillion times smaller than Earth’s, MacCallum and Poynter noticed.

“It's very hard on the Earth to get that tight a visceral connection between your behavior and the environment,” MacCallum says.

Today, the imposing white dome of Biosphere 2 still rises above the Arizona desert like a cross between a greenhouse and the Taj Mahal. Now, it’s a research station maintained by the University of Arizona where researchers study Earth processes, global environmental change, weathering, landscape evolution, and the effect of drought on rainforests, among many projects. Because of its systems and size, scientists can do controlled experimentation at an unprecedented scale in Biosphere 2.

Another view of Biosphere 2. Image credit: © CDO courtesy of the University of Arizona

MacCallum and Poynter returned to Biosphere 2 in May 2016 for the One Young World Environmental Summit to speak to young environmental leaders from around the world. But in the early 1990s, they and six others were sealed inside it for two years and 20 minutes, from September 26, 1991 to September 26, 1993, in a life-changing experiment that was equal parts humility and hubris—both shortsighted and ahead of its time.

“The big questions of the two-year mission,” says MacCallum, were, “Can we build artificial biospheres? Can these be objects of science? Can we learn from them?”

We could and did. As a result of their voluntary containment, we learned how to seal a giant building so that it loses less air than the International Space Station, manage damaged coral reefs, feed eight people on a half-acre of land, and recycle water and human waste in a closed system, among other things.

The structure itself, built from 1987 to 1991, is a technological marvel even today. The idea was to build a miniaturized biosphere completely separated from Earth, see if humans could live inside it, and see how they affected the animals and plants around them and vice versa. (Why call it Biosphere 2? Because Earth is Biosphere 1.) It’s roughly as tightly sealed as the space station and separated from the soil around it by a 500-ton steel liner.

In the early '90s, when the mission started, the ideas that humans were causing climate change or even that Earth was a biosphere at all were much less accepted than they are today. “When we started this project, I was spelling the word ‘biosphere’ down the phone,” says MacCallum.

Much the way a botanical garden's conservatory is, Biosphere 2’s glass-walled domes and pyramids were filled with different biomes: rainforest, ocean (with a coral reef), savannah, desert, mangrove swamp, and agricultural fields in which the team grew all their crops. They ate so many sweet potatoes that Poynter turned orange, but their world also included domestic animals: goats (their only dairy source), chickens, pigs, and tilapia. They had only enough coffee plants to make one cup of coffee per person every few weeks.

The desert biome in Biosphere 2. Image credit: © CDO courtesy of the University of Arizona

Problems quickly developed. The coral reef became overgrown with algae. Most of the pollinating insects died. A bush baby in the rainforest biome got into the wiring and was electrocuted. Each of the crew members had a primary job: Poynter was in charge of the farm and farm equipment, and MacCallum was in charge of the analytical chemistry lab inside Biosphere 2. The crew had to do all their research, farming, and experiments while hungry because they weren’t getting enough calories.

More dangerous was the decline in oxygen. That night in 1992, their oxygen levels dipped temporarily, but overall their oxygen levels declined from 20.9 percent to 14.5 percent. (Any environment below 19.5 percent oxygen is defined as oxygen-deficient by the Occupational Safety and Health Administration, or OSHA.) The low oxygen made them lethargic. For months they couldn’t sleep properly because it gave them sleep apnea. Scientists were monitoring them and communicating with them from the outside, and finally in August 1993, just a month before the crew left Biosphere 2, they decided to start pumping in oxygen.

Taber MacCallum tests air conditions in Biosphere 2. Image credit: © CDO courtesy of the University of Arizona

Later, scientists figured out that the culprits were microbes proliferating in the Biosphere’s compost-rich soil, combined with the building’s concrete. The microbes themselves were not harmful, but they converted oxygen into carbon dioxide, which then reacted with the building’s concrete to form calcium carbonate and irreversibly remove oxygen molecules from the Biosphere's atmosphere.

Still, looking back more than two decades years later, MacCallum and Poynter view the experiment as a success. Its initial science findings have been developed on in the years since—the University of Arizona has owned the facility since 2007—and its research focus remains as big picture as it ever was: global environmental change.

Beyond the science, even just seeing Biosphere 2 could change people’s perspectives. Poynter recalls getting an email while she was inside Biosphere 2 from a man who walked around the perimeter of the structure as part of the monitoring effort, who said, “'I get it now, because I walked around Biosphere 2, this miniature version of planet Earth, and it smacked me in the face: you guys only have what you have in there, and you have nothing else.'”

“That is fundamentally the message: that it's finite,” Poynter says. “And also very resilient.”

When after two years they finally emerged, Poynter had lost virtually all the enzymes to digest meat from eating so little of it. Nevertheless, she says, “Physically, we were in pretty decent shape. I had spent every day farming, so I was pretty strong.”

Jane Poynter checks on the goats in Biosphere 2. Image credit: © CDO courtesy of the University of Arizona

Still, it was a huge change. “The experience of coming out of Biosphere 2 was amazing in that it was like being reborn into this world and seeing it with fresh eyes,” she recalls. That night they had a big party with friends they hadn’t seen in two years. “And then the next morning there was this giant pile of garbage. It was this stark reminder of this consumable world that we live in.”

Poynter and MacCallum, who were dating when they entered Biosphere 2, married nine months after leaving it. Together with three others, they formed Paragon Space Development Corporation. Over the years, they developed a range of aerospace technology, including temperature control and life support systems for NASA and SpaceX that could be used to support people on the Moon or on Mars.

Their current company, World View Enterprises, spun out of Paragon in 2013. Key staff include chief scientist Alan Stern, head of the New Horizons mission to Pluto, and astronaut Mark Kelly (twin brother of astronaut Scott Kelly), who is the director of flight crew operations. World View sends uncrewed vehicles high up in the near-space stratosphere to research weather and other phenomena, and aims to one day bring people up to where the sky is black, the Earth looks curved, and it’s visibly clear that Earth is the home we share.

The curvature of the Earth as captured by a World View craft. Image credit: World View

It's that big-picture view that Poynter and MacCallum want to share with others. After talking with astronauts, they think that the “overview effect” astronauts feel when seeing the Earth from space is not unlike what they felt in Biosphere 2. Like Poynter and MacCallum, astronauts describe feeling deeply moved by the experience to do something to help Earth and its people.

Poynter says the company’s technology is proprietary and has to do with buoyancy control. “The basis of it is our ability to do very accurate altitude control,” she says, which allows their vehicles to take advantage of prevailing winds at different altitudes to travel exactly where they want.

World View Enterprises is particularly interested in taking leaders and influencers up to the stratosphere. Because you can’t just lock world leaders inside a biosphere in the desert for two years to give them the insight that Poynter and MacCallum know so deeply: We, as humans, are fully connected to and dependent on our environment.

“In the biosphere," Poynter says, "I really fell in love with the Earth."

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Big Questions
How Long Could a Person Survive With an Unlimited Supply of Water, But No Food at All?
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How long could a person survive if he had unlimited supply of water, but no food at all?

Richard Lee Fulgham:

I happen to know the answer because I have studied starvation, its course, and its utility in committing a painless suicide. (No, I’m not suicidal.)

A healthy human being can live approximately 45 to 65 days without food of any kind, so long as he or she keeps hydrated.

You could survive without any severe symptoms [for] about 30 to 35 days, but after that you would probably experience skin rashes, diarrhea, and of course substantial weight loss.

The body—as you must know—begins eating itself, beginning with adipose tissue (i.e. fat) and next the muscle tissue.

Google Mahatma Gandhi, who starved himself almost to death during 14 voluntary hunger strikes to bring attention to India’s independence movement.

Strangely, there is much evidence that starvation is a painless way to die. In fact, you experience a wonderful euphoria when the body realizes it is about to die. Whether this is a divine gift or merely secretions of the brain is not known.

Of course, the picture is not so pretty for all reports. Some victims of starvation have experienced extreme irritability, unbearably itchy skin rashes, unceasing diarrhea, painful swallowing, and edema.

In most cases, death comes when the organs begin to shut down after six to nine weeks. Usually the heart simply stops.

(Here is a detailed medical report of the longest known fast: 382 days.)

This post originally appeared on Quora. Click here to view.

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NSF/LIGO/Sonoma State University/A. Simonnet
Astronomers Observe a New Kind of Massive Cosmic Collision for the First Time
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NSF/LIGO/Sonoma State University/A. Simonnet

For the first time, astronomers have detected the colossal blast produced by the merger of two neutron stars—and they've recorded it both via the gravitational waves the event produced, as well as the flash of light it emitted.

Physicists believe that the pair of neutron stars—ultra-dense stars formed when a massive star collapses, following a supernova explosion—had been locked in a death spiral just before their final collision and merger. As they spiraled inward, a burst of gravitational waves was released; when they finally smashed together, high-energy electromagnetic radiation known as gamma rays were emitted. In the days that followed, electromagnetic radiation at many other wavelengths—X-rays, ultraviolet, optical, infrared, and radio waves—were released. (Imagine all the instruments in an orchestra, from the lowest bassoons to the highest piccolos, playing a short, loud note all at once.)

This is the first time such a collision has been observed, as well as the first time that both kinds of observations—gravitational waves and electromagnetic radiation—have been recorded from the same event, a feat that required co-operation among some 70 different observatories around the world, including ground-based observatories, orbiting telescopes, the U.S. LIGO (Laser Interferometer Gravitational-Wave Observatory), and European Virgo gravitational wave detectors.

"For me, it feels like the dawning of a next era in astrophysics," Julie McEnery, project scientist for NASA's Fermi Gamma-ray Space Telescope, one of the first instruments to record the burst of energy from the cosmic collision, tells Mental Floss. "With this observation, we've connected these new gravitational wave observations to the rest of the observations that we've been doing in astrophysics for a very long time."


The observations represent a breakthrough on several fronts. Until now, the only events detected via gravitational waves have been mergers of black holes; with these new results, it seems likely that gravitational wave technology—which is still in its infancy—will open many new phenomena to scientific scrutiny. At the same time, very little was known about the physics of neutron stars—especially their violent, final moments—until now. The observations are also shedding new light on the origin of gamma-ray bursts (GRBs)—extremely energetic explosions seen in distant galaxies. As well, the research may offer clues as to how the heavier elements, such as gold, platinum, and uranium, formed.

Astronomers around the world are thrilled by the latest findings, as today's flurry of excitement attests. The LIGO-Virgo results are being published today in the journal Physical Review Letters; further articles are due to be published in other journals, including Nature and Science, in the weeks ahead. Scientists also described the findings today at press briefings hosted by the National Science Foundation (the agency that funds LIGO) in Washington, and at the headquarters of the European Southern Observatory in Garching, Germany.

(Rumors of the breakthrough had been swirling for weeks; in August, astronomer J. Craig Wheeler of the University of Texas at Austin tweeted, "New LIGO. Source with optical counterpart. Blow your sox off!" He and another scientist who tweeted have since apologized for doing so prematurely, but this morning, minutes after the news officially broke, Wheeler tweeted, "Socks off!") 

The neutron star merger happened in a galaxy known as NGC 4993, located some 130 million light years from our own Milky Way, in the direction of the southern constellation Hydra.

Gravitational wave astronomy is barely a year and a half old. The first detection of gravitational waves—physicists describe them as ripples in space-time—came in fall 2015, when the signal from a pair of merging black holes was recorded by the LIGO detectors. The discovery was announced in February 2016 to great fanfare, and was honored with this year's Nobel Prize in Physics. Virgo, a European gravitational wave detector, went online in 2007 and was upgraded last year; together, they allow astronomers to accurately pin down the location of gravitational wave sources for the first time. The addition of Virgo also allows for a greater sensitivity than LIGO could achieve on its own.

LIGO previously recorded four different instances of colliding black holes—objects with masses between seven times the mass of the Sun and a bit less than 40 times the mass of the Sun. This new signal was weaker than that produced by the black holes, but also lasted longer, persisting for about 100 seconds; the data suggested the objects were too small to be black holes, but instead were neutron stars, with masses of about 1.1 and 1.6 times the Sun's mass. (In spite of their heft, neutron stars are tiny, with diameters of only a dozen or so miles.) Another key difference is that while black hole collisions can be detected only via gravitational waves—black holes are black, after all—neutron star collisions can actually be seen.


When the gravitational wave signal was recorded, on the morning of August 17, observatories around the world were notified and began scanning the sky in search of an optical counterpart. Even before the LIGO bulletin went out, however, the orbiting Fermi telescope, which can receive high-energy gamma rays from all directions in the sky at once, had caught something, receiving a signal less than two seconds after the gravitational wave signal tripped the LIGO detectors. This was presumed to be a gamma-ray burst, an explosion of gamma rays seen in deep space. Astronomers had recorded such bursts sporadically since the 1960s; however, their physical cause was never certain. Merging neutron stars had been a suggested culprit for at least some of these explosions.

"This is exactly what we'd hoped to see," says McEnery. "A gamma ray burst requires a colossal release of energy, and one of the hypotheses for what powers at least some of them—the ones that have durations of less than two seconds—was the merger of two neutron stars … We had hoped that we would see a gamma ray burst and a gravitational wave signal together, so it's fantastic to finally actually do this."

With preliminary data from LIGO and Virgo, combined with the Fermi data, scientists could tell with reasonable precision what direction in the sky the signal had come from—and dozens of telescopes at observatories around the world, including the U.S. Gemini telescopes, the European Very Large Telescope, and the Hubble Space Telescope, were quickly re-aimed toward Hydra, in the direction of reported signal.

The telescopes at the Las Campanas Observatory in Chile were well-placed for getting a first look—because the bulletin arrived in the morning, however, they had to wait until the sun dropped below the horizon.

"We had about eight to 10 hours, until sunset in Chile, to prepare for this," Maria Drout, an astronomer at the Carnegie Observatories in in Pasadena, California, which runs the Las Campanas telescopes, tells Mental Floss. She was connected by Skype to the astronomers in the control rooms of three different telescopes at Las Campanas, as they prepared to train their telescopes at the target region. "Usually you prepare a month in advance for an observing run on these telescopes, but this was all happening in a few hours," Drout says. She and her colleagues prepared a target list of about 100 galaxies, but less than one-tenth of the way through the list, by luck, they found it: a tiny blip of light in NGC 4993 that wasn't visible on archival images of the same galaxy. (It was the 1-meter Swope telescope that snagged the first images.)


When a new star-like object in a distant galaxy is spotted, a typical first guess is that it's a supernova (an exploding star). But this new object was changing very rapidly, growing 100 times dimmer over just a few days while also quickly becoming redder—which supernovae don't do, explains Drout, who is cross-appointed at the Dunlap Institute for Astronomy and Astrophysics at the University of Toronto. "We ended up following it for three weeks or so, and by the end, it was very clear that this [neutron star merger] was what we were looking at," she says.

The researchers say they can't be sure if the resulting object was another, larger neutron star, or whether it would have been so massive that it would have collapsed into a black hole.

As exciting as the original detection of gravitational waves last year was, Drout is looking forward to a new era in which both gravitational waves and traditional telescopes can be used to study the same objects. "We can learn a lot more about these types of extreme systems that exist in the universe, by coupling the two together," she says.

The detection shows that "gravitational wave science is moving from being a physics experiment to being a tool for astronomers," Marcia Rieke, an astronomer at the University of Arizona who is not involved in the current research, tells Mental Floss. "So I think it's a pretty big deal."

Physicists are also learning something new about the origin of the heaviest elements in the periodic table. For many years, these were thought to arise from supernova explosions, but spectroscopic data from the newly observed neutron star merger (in which light is broken up into its component colors) suggests that such explosion produce enormous quantities of heavy elements—including enough gold to put Fort Knox to shame. (The blast is believed to have created some 200 Earth-masses of gold, the scientists say.) "It's telling us that most of the gold that we know about is produced in these mergers, and not in supernovae," McEnery says.

Editor's note: This post has been updated.


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