# @downinnadesert on Instagram

- **Type:** Image
- **Original URL:** https://www.instagram.com/p/DdH91-lDyN8
- **Gondola URL:** https://gondola.cc/posts/70299987-downinnadesert-instagram
- **Thumbnail:** https://img.gondola.cc/tr:w-,h-,fo-auto/postThumbnails/70367ce28d.jpg
- **Posted:** 2026-09-10T23:00:01.000+00:00
- **Account Owner:** Down In The Desert🌵 (@downinnadesert) — https://gondola.cc/downinnadesert

## Caption

Sixteen months into a two-year experiment, eight people sealed inside a glass building in the Arizona desert were slowly running out of oxygen, and nobody could figure out where it was going.

Biosphere 2 sits near Oracle, north of Tucson. Built with roughly $150 million from billionaire Ed Bass, the massive glass complex contained a rainforest, ocean, mangrove wetland, savannah, desert, agricultural area and living quarters.

On September 26, 1991, eight people entered and the doors were sealed behind them for two years. They had to grow their own food, recycle their water and maintain their own atmosphere.

Then the oxygen started disappearing.

It began around 20.9%, but over 16 months fell to roughly 14.5%, similar to breathing at about 13,000 feet. Crew members became exhausted, struggled climbing stairs and sometimes had to stop mid-sentence to catch their breath.

The oxygen wasn’t simply leaking out.

Microorganisms in the soil were consuming oxygen and releasing carbon dioxide. But the complex contained huge amounts of exposed concrete, which absorbed much of that CO2 as it cured.

So the oxygen was disappearing while the evidence was literally being trapped inside the structure.

The building was basically eating the air.

Outside oxygen eventually had to be pumped in, but the crew still completed the full two-year mission and walked out on September 26, 1993.

Today, the University of Arizona operates Biosphere 2 for Earth and climate research, and you can still tour it.

Have you ever been inside Biosphere 2? 👀

Send us your Arizona stories to be featured.

#Oracle #Tucson #Biosphere2 #Arizona #ArizonaHistory

## Stats

- **Views:** 0
- **Likes:** 558
- **Shares:** 0
- **Comments:** 21

## Tags

oracle, arizonahistory, tucson, arizona, biosphere2

---
Copyright (c) Gondola