|
The International Space Station and the fictional Venus Equilateral Station (from a 1942 story by George O. Smith) have a problem in common - a failure of the "air plant."
(Elektron Oxygen Generator Diagram)
The ISS uses (among other components) the Elektron oxygen generation system. After several stoppages, the unit failed completely about a month ago. Astronauts are now using SFOG (solid-fuel oxygen generator) "candles" at a rate of one per person per day.
In his 1940's Venus Equilateral station series, author George O. Smith runs into this problem in the very first story. A bureacrat from Earth arrives to fill the post of station Director; shortly after his arrival, all of the inhabitants of the station suffer from oxygen deprivation. The problem? On an inspection, he looks into a room labeled 'air plant' and finds - a jungle of weeds! Naturally, he has them removed.
(Sawgrass)
Turns out the weeds are Martian sawgrass:
"What better purifying machine is there than a plot of grass?" shouted Channing. "... We breathe oxygen, exhale CO2. Plants inhale CO2 and exhale oxygen. An air plant means just that. It is a specialized type of Martian sawgrass that uses chlorophyll... We've spent years getting that plant so it will grow just right. It got so good that the CO2 detectors weren't even needed...
(Read more about Martian sawgrass)
It turns out that NASA worked on a related problem in the 1970's. They found that the air inside Sky Lab 3 was contaminated with more than 100 toxic substances. They put environmental engineer Bill Wolverton, PhD, to the task of ensuring cleaner air. After much research, he found that plants provided a solution. He found that common plants like Boston fern, dracaena, Ficus benjamina (rubber plant), and chrysanthemum eliminated up to 90% of such poisons as benzene, formaldehyde, and trichloroethylene from enclosed spaces. Dr. Wolverton noted that plants actually get better at the task of removing pollutants over time, saying "The longer a plant is exposed to certain chemicals, the more effective it becomes at removing them."
I've been paging through some of the Mars rover pictures looking for little clumps of sawgrass - no luck there. But maybe a solar-powered chlorophyll-based 'air plant' might be just what a space station needs.
If you are interested in the subject of space-based horticulture, see Robotic Tomato Harvester Ready For Space and Chinese Seed Satellite. Read a bit more about the Ektelon Generator Failure. Thanks to reader Christopher Thomas for providing additional material for this article.
http://www.livescience.com/scienceoffiction/050718_station_air.html
|
