NASA astronaut Sandra Magnus was among six astronauts aboard NASA's final shuttle mission in July. Photo Credit/NASA photo
During NASA’s final shuttle mission in July, astronauts demonstrated techniques borrowed from nature that may help future fliers on spacewalks, or even explorers on long missions to distant planetary bodies, recycle impure water for drinking.
The process is called forward osmosis. It’s already used by backpackers and on a grander scale by desalinization plants on Earth to filter impurities from non potable water.
Gravity is an essential part of the natural process. But the Atlantis crew took some time from their primary duties of delivering supplies to the International Space Station to demonstrate that forward osmosis can work in weightlessness.
In nature, living cells rely on forward osmosis to draw water through a semi-permeable membrane. The membrane acts as a filter that permits the passage of small water molecules, while it blocks unwanted salts, sugars, starches, proteins and harmful micro organisms like protozoan parasites, bacteria and viruses.
The Atlantis astronauts recreated the process in the absence of gravity with a Forward Osmosis Bag developed with the help of scientists from QinetiQ North America. By shaking the bags for several minutes, the shuttle crew demonstrated that water will pass through a commercially manufactured membrane to remove impurities.
Experimenters believe the same process could be used during spacewalks, for instance, to purify water. The natural exertion of the spacewalking astronauts could be enough to recover drinkable water from perspiration, even urine.
Up scaled, the same process could be used by astronauts on deep space missions to recover drinking water, researchers believe. Forward osmosis could lower the weight of the supplies and equipment required to start the mission — a potential cost saver.
The 13-day July flight of Atlantis marked the 135th and final flight of NASA’s long running shuttle program. Six astronauts participated.