Nov 26, 2008

Science - After Vital Repairs, Space Station on Track for Larger Crews

Tariq Malik

The apparently successful fix of a solar array-rotating gear and a recycling system that turns urine into drinkable water have set the stage for the International Space Station to ramp up to six-astronaut crews next year, but only after a battery of tests confirm the repairs, NASA officials said Tuesday.


Space station program manager Mike Suffredini said the in-space repairs by station and Endeavour shuttle astronauts to the urine recycler and a massive starboard-side gear have put the orbiting lab on course for next year's plan to double the size of its current three-person crews.


"I would say we're on the right track," Suffredini said of the repairs, adding that Endeavour's mission is capping a series of recent shuttle missions to expand the space station. "We've made a major step towards a six-person crew with just one flight."


Astronauts proudly displayed a batch of the recycled water to NASA television cameras on Tuesday. It was labeled with a sign reading "Yesterday's Coffee," a running joke among the crew, which has said the new recycler turns "yesterday's coffee into today's coffee."


Foundation set for crew boost


The first six-person crew is expected to take up residence aboard the station in late May of next year. Those astronauts will be greeted by a host of vital systems delivered aboard Endeavour.


Commanded by astronaut Chris Ferguson, Endeavour's seven-astronaut crew arrived at the space station last week carrying a new crewmember, two spare bedrooms, exercise gear, a second kitchen and bathroom along with the recycling system for urine and wastewater.


Also aboard were three astronauts who performed a four-spacewalk overhaul the 10-foot (3-meter) wide gear by replacing bearings, greasing up its metal ring and cleaning metal shavings from its delicate mechanism. The gear is one of two designed to rotate the space station's wing-like solar arrays so they always face the sun and maximize power, but it hasn't worked properly in over a year.


Suffredini said the fixes by Endeavour's crew appear to have done the trick. Flight controllers rotated the repaired gear for three hours early Tuesday as the space station orbited Earth twice. But weeks of more tests will determine the full measure of the repair, Suffredini said.


So, too, with the urine recycler, which astronauts spent days repairing after a series of start-up glitches late last week. The high-tech wastewater system is designed to collect astronaut urine, sweat and other condensate and filter it through a seven-step process back into potable water. The end result is fresh water for drinking, food preparation, bathing and oxygen generation.


The ability to recycle urine and wastewater aboard the station is vital to support larger crews since it reduces the amount of potable water delivered to the orbiting lab aboard visiting spacecraft. That saved space, about the equivalent of about 743 gallons (2,850 liters) per year, frees up room for other cargo and supplies.


NASA extended the Endeavour crew's mission by a day to allow the extra work, which included removing small vibration dampeners and adding braces to bolt a centrifuge down more securely. The repair appeared to be a success, with the recycler processing urine as designed for more than five hours Tuesday.


Endeavour will return six quart-size (1-liter) samples of the recycled water for analysis. Engineers expect to spend three months testing the system before clearing the water for astronaut consumption.


"You have to remember that this is serial number 001 for one our brand new technologies which we're testing out here on space station," said Endeavour astronaut Don Pettit. "So you can expect to have a few hiccups."


NASA is providing live coverage of Endeavour's STS-126 mission on NASA TV. Click here for SPACE.com's mission coverage and NASA TV feed.

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