Electrical service upgraded in space

Two spacewalking astronauts successfully rewired half of the International Space Station on Thursday, a job that when finished will allow the orbiting outpost to double the size of its crew and add two more labs in the coming years.

Flight controllers on the ground happily reported to the space station that power was flowing through two electrical channels hooked up by astronauts Robert Curbeam and Christer Fuglesang.

“Excellent. Excellent,” said astronaut William Oefelein, who was coordinating the spacewalk from inside the orbiting outpost, which has a crew of three.

NASA immediately started powering up systems aboard a large section of the space station; the power had to be turned off for the spacewalkers’ safety while they were handling the electrical connections.

The space agency also rushed to get the station’s ammonia cooling system operating again before the new electrical equipment overheated. It took less than an hour for the cooling system to start running smoothly.

It was the second spacewalk for Curbeam and Fuglesang since space shuttle Discovery arrived at the orbiting lab for a seven-day visit. The five-hour foray ended at 4:41 p.m. PST, a full hour earlier than planned.

The rewiring job involved switching the space station from its old, temporary power source to a pair of solar arrays that were delivered in September. The spacewalkers had to unhook three dozen electrical hoses and reconnect them. The astronauts also completed some housekeeping tasks.

The trip outside the spacecraft brought the total of spacewalking time dedicated to assembling the space station to 455 hours and 50 minutes, said NASA spokeswoman Nicole Cloutier.

During a short break, the spacewalkers watched shooting stars and the blaze of the aurora borealis, or northern lights, a phenomenon caused by solar flares colliding with Earth’s atmosphere.

A third spacewalk set for Saturday will repeat the rewiring job, but on the flip side of the station’s U.S. segment.