Astronauts successfully complete first of three spacewalks

International Space Station Commander Mike Lopez-Alegria and Flight Engineer Sunita Williams on Wednesday successfully completed a 7-hour 55-minute spacewalk at 6:09 p.m. EST. During their trip outside the station the two spacewalking astronauts successfully switched half the outpost’s coolant lines into a permanent cooling system.

It was Lopez-Alegria and Williams’ first of three spacewalks planned outside the international space station over the next nine days. They are scheduled to make the second spacewalk on Feb. 4 and the third for Feb. 8. The first two ventures concentrate on the reconfiguration of station power and cooling systems to permanent ones.

The astronauts switched electrical and fluid lines from interim to permanent locations on the station’s girder like supporting truss. They took extra time to do the tedious job of disconnecting potentially leaky ammonia lines and delicately attaching the new system, exceeding a planned time of six and one-half hours.

Lopez-Alegria, the lead spacewalker wearing the suit with red stripes, and Williams in the all-white suit were running low on time and spacesuit battery power, so they had to stop any extra tasks, known as "get-aheads", at the end of first spacewalk outside the ISS.

They began the tasks of the first spacewalk by reconfiguring one of the two cooling loops, ‘Loop A’ & ‘Loop B’, serving Destiny from the temporary to the permanent system.

"That looked pretty difficult," spacewalk engineer Chris Looper at the Mission Control Centre in Houston, told the spacewalkers. "I feel for you."

During Wednesday's spacewalk 220 miles above Earth, four or five flakes of toxic ammonia fell from a cooling line cap, similar to 2001 incident when the toxic substance leaked out of a cooling line onto astronaut Robert Curbeam's spacesuit when he was performing the same task. However, this time the substance did not touch Lopez-Alegria and Williams, both of the Navy.

The leak took place at the time when Williams, who was making her second spacewalk, and Lopez-Alegria, on his seventh, disconnected and prepared to stow away two fluid lines that had been connected to an ammonia reservoir outside the space station.

Though the substance did not touch the spacewalkers’ spacesuit, still Mission Control told them to remain in their spacesuits for some time to make sure there was no ammonia on their suits that could contaminate the orbiting lab.

Lopez-Alegria and Williams spent about 25 minutes in a "bakeout" after they had re-entered the airlock, in order to prevent any possibility of ammonia from the fluid lines entering the station. Tests in the airlock later detect no contamination.

"We don't think we have contamination, but that's probably for the lawyers," Lopez-Alegria said. Replied Mission Control: "We're going to follow the path of safety."

Lopez-Alegria made electrical connections for a new system that will allow power from the ISS to be shared with a docked shuttle.

The two astronauts are to perform a nearly identical spacewalk on Sunday (Feb-04) to complete the cooling system switch, and on Thursday (Feb-08) they will remove some thermal blankets from part of the truss and set up two external platforms for stowing cargo.