July 7, 2011 By Chad Vander Veen
Answer: Urinate into a baggie.
The Forward Osmosis Bag (FOB) system, according to NASA, "is designed to convert dirty water into a liquid that is safe to drink using a semi-permeable membrane and a concentrated sugar solution. "
Wired reports the bag "makes about a liter of sports drink-like fluid in four to six hours" and does not require external power. The bag will be aboard the final Space Shuttle launch.
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