The crew on the International Space Station has been collecting something special for weeks now, waiting for the Space Shuttle Endeavour to deliver the new Water Recycling Unit for installation on the space station.
The unit, known as the WRS, was finally installed Tuesday and will be hooked up to the new $19 million dollar toilet that is being added during this mission. It will be used to recycle astronauts' urine and sweat, and turn it into drinking water.
The next step for the astronauts is to hook it up and fill it with the urine the crew has been saving for this occasion.
The toilet is equipped with funnels that will channel the liquids to the WRS, which then runs solid materials like hair and lint through a series of filters. Any other contamination will be scrubbed using a high temperature catalytic reaction to create safe drinking water.
Flight director Ginger Kerrick hopes to test the samples on flight day 11. It takes two days to process a batch of water, but the first batch will not be used for drinking.
"We are not partaking of the samples on orbit; we are bringing them home for analysis," Kerrick said.
Don Pettit, who is on his second space mission, said that before now, with regular drinking and urination, astronauts in orbit basically used their water once and threw it away. But that isn't practical for long-term living in space, where a limited amount of water can be transported at a time.
"Water is a precious commodity when you leave Earth," he said. "Here on Earth we just take new water and use it, then let nature recycle it for us, and we have to learn to do that."
Pettit said this system is unique to the space station.
"You don't do that on submarines, you don't do it in Antarctica, and you don't do it in the Arctic. There is no scientific frontier environment where people basically recycle their own urine," she said.
If successful, the WRS system will be crucial to some of the long-term missions NASA is planning for the future.
"This is the most significant event of this mission, because without this technology we won't be able to go back to the moon, or support life on a three-year journey to Mars," said LeRoy Cain, the mission management chairman for this mission.
Of course, the thought of drinking recycled urine might make some squeamish, but not Pettit.
"The space station is a testing ground and we are learning how to make robust life support technology that allows us to squeak every drop of water out of the process," he said. " We plan to make coffee with [it]."