ROKKASHO, Japan — Masanori Shinohara was working as a researcher studying dolphin behavior when his wife commented on a newspaper ad seeking scientists to populate a "mini Earth."
Shinohara began checking into it. "It sounded interesting, but I couldn't figure out what it was about" at first, he says
It turned out to be a Japanese version of the ballyhooed, but far-from-successful, Biosphere 2 experiment in the early 1990s in which eight scientists were sealed in a compound in Oracle, Ariz.
Shinohara was intrigued, applied for a spot and was selected.
He's counting down the months until he and chemist Osamu Komatsubara become the first human residents in 2005 at the facility erected in Rokkasho, a small farming and fishing town on Japan's northern coast.
Mini Earth is less ambitious than the 3.15-acre, $200-million Biosphere 2, which had its own ocean, desert, savanna and rainforest.
With a construction budget of $65 million, the 1.16-acre Mini Earth was completed two years ago. Researchers have since been doing preliminary experiments inside the compound, which consists of three gymnasium-sized buildings connected by stainless-steel corridors.
The project calls for the two scientists to be sealed off with animals and plants in the air-locked structure for about a week at first, then for stretches of up to five months.
The goal is to simulate the cycle of oxygen and carbon dioxide among plants, humans and animals in a sealed environment.
Along with providing insights into the cycles and interactions themselves, the perfecting of self-sustaining environments could have important applications in the exploration of space and oceans.
One of the problems that plagued Biosphere 2 was the consumption of oxygen.
Though intended to be a self-sustained, self-contained living system, oxygen had to be pumped into Biosphere 2 because microbes in its soil consumed oxygen faster than the plants inside could produce it. The facility's concrete walls also trapped carbon dioxide, impeding the growth of plants.
Keiji Nitta, a rocket scientist and senior executive director at the Institute for Environmental Sciences, which supervises Mini Earth, says he is confident that won't be a problem in Japan's project.
"One of the big differences from Biosphere 2 is that we put a lot of money and time into designing and making our life-support system," Nitta said.
