Biosphere 2 becomes a ‘big science’

As you approach the turnoff to Biosphere Road, 30 miles north of Tucson on State Highway 77, you see nothing but the Sonoran Desert of southern Arizona and a couple of odds and ends of semi-civilization. There is a rock with the Biosphere 2 logo. There is a flag pole. At the flagpole, in order from top to bottom, wave (1) that star-spangled banner that disgusts the current Washington administration so much, (2) the stellar explosion of Arizona Copper State, and finally the flag “A” from the University of Arizona.

Turn right (if heading north). Pass a couple miles past cattle crossings, a copper mine, an electrical substation that has nothing to do with B2, and an empty guard post at the entrance to what was once Sunspace Ranch. Along the way, you can catch a glimpse of what Columbia University called “The Gadget” when they ran the place. Finish off in a tree-lined parking lot next to a driveway outfitted with fabric shade sails. Be on the lookout for snakes.

Just to get you out of the way, keep in mind that Biosphere 2 offers “under glass” tours inside the 3.14-acre biosphere apparatus (the U of A likes to call it “The Sphere”) from 9am to 4pm. M. At 4 p. M., 363 days a year. except for Thanksgiving Day and Christmas Day, which they call “December 25th.” They do tours even if it snows a little. (Biosphere 2 is 3,900 feet above mean sea level, 1,400 feet above downtown Tucson.) They do so even if the summer monsoons are raging in the foothills of Catalina Mountain, where the Biosphere is located, as long as it is deemed safe. For ticket prices (about $ 20), you will have called 520-838-6200. Voice is automated so you will NOT find out this way that you can get a better deal with membership, as revealed by the B2Science website. See “Links” at the end of the article.

The website also explains why people with physical limitations may not be able to manage the tour. Stairs are unavoidable. The balance can be uncertain. You have to watch your head. You have to watch your steps. You have to look at both at the same time.

Well, it can’t be that bad. More than 100,000 visitors a year come this way, from 100 a day or less in the summer months, when tours run 1 hour and 15 minutes apart, up to 900 a day in the winter, when tours start every 15 minutes. Add in the ten minutes or so it takes to amble back to the starting point, and you should spend 90 minutes on the tour, not counting bathroom breaks, walking through underwater caves to see the artificial ocean floor, or visiting what which was the human habitat when Biosphere 2 was home to “biospheres”. Fifteen biospheres in two “missions” lived there in simulated space colony conditions from 1991 to 1994. There is a souvenir shop. There is a “cafeteria”, but its offer is limited, as are its hours. If you’re not in a rush, Biosphere 2 is good for 2.5 hours.

You start the tour with a 10 minute movie. Make a wake-up call if you don’t care about party line, because it’s about political imagery. It tells the viewer that the “Sphere” is the only place where certain experiments can be performed and therefore the U of A must control the Sphere, or the world will end. You will hear it over and over again throughout the tour. If you question the concept, you’ll hear it one more time, along with the words “I said that,” so don’t torture the tour guide.

Pay attention to the signs posted everywhere proclaiming that the Biosphere is now, thanks to the University of Arizona, “Big Science.”

Be that as it may, Biosphere 2 is a feat of engineering. That becomes clear when your guide points out construction details such as the hermetically sealed, triple-pane glass and steel structure, the cave-shaped air registers and massive returns, the network of rain pipes on the roof. and the artificial ocean wave machine. The tour will include a passage through the “Technosphere”, domain of air handlers, chillers, pumps, tanks, reverse osmosis filters, circuits and pipes. Above, you may have noticed that the rainforest could be operating at 120 degrees Fahrenheit with 90% relative humidity, while the coastal desert at 85 degrees with 25% humidity. Each biome has its own independent environmental control system in the technosphere.

While the temperature inside the glass must vary with the time of day and season to mimic the Earth, it is essential that the pressure variation inside does not exceed the limits of resistance of the glass (Charles Law, people, chemistry of the high school). The problem is solved by using two “lung” structures covered by a dome to the south and west of the main Biosphere. Inside each white protective dome, there is a cylinder covered by a rubber diaphragm (Hypalon) that lifts a central weight. Both the diaphragm and the disc-shaped weight form the roof of the wide cylinder connected to the Biosphere by a tunnel. The weight controls the pressure and the diaphragm rises or falls like a piston to convert what would otherwise be a change in pressure to a change in volume as it rises and falls during the day (Boyle’s Law). Your tour will visit the southern lung, with its added feature of a 250,000 gallon tank to collect “rainwater” for recycling. With a pair of massive pumps visible above the central pool on the floor, the reservoir also provides a fire suppression service for the Biosphere.

When exiting the southern lung to the outside world, hold on to the hat. A fierce wind will blow you out when you go through the hatch. That wind will provide the best evidence for positive air pressure within the biosphere.

Later, while touring the habitat dwellings on your own, be sure to visit the bath. You will find the usual toilet paper in a roll, but it will be in an awkward place, as if the bathroom was not designed to hold it. It was not. Note the hose and valve on the wall. It is a bidet. The biospheres never used toilet paper. The sewage treatment plant was, well, plants, in the saltwater marsh. Everything, including sewage, was recycled to maintain closed-loop life. Today, of course, the bathroom is connected to a standard septic system. That will be your best evidence that Biosphere 2 is no longer closed to the outside.

In fact, Biosphere 2 has been reconfigured to allow selected gases (mainly carbon dioxide) to enter and exit. Using this method, the composition of their atmosphere can be precisely controlled, as is necessary to do the kind of science they do there now. Water is no longer fully recycled. If it were, the isotopic markers used to pinpoint the drain source would be counted twice.

Biosphere 2 is an ecology laboratory, but its appearance and its atmosphere preserve the romanticism of its history in a place that, at times, evokes the magnificent desolation of the Red Planet. Only the most hollowed-out and passionate visitors buy the history of “Big Science.” Really, they are going to Mars.


Leave a Reply

Your email address will not be published. Required fields are marked *