The spacewalk, first scheduled for Thursday, was originally intended to inspect a gummed-up rotary joint that keeps electricity-generating solar panels aimed at the sun. But flight communicator Tony Antonelli radioed from Mission Control on Wednesday to say that things had changed.
"We're going to shoot for (a spacewalk on) flight day 11 (Friday) and if we get that accomplished, the content of which will be solar array wing stuff," he told the 10 astronauts on the station and the docked space shuttle Discovery.
The abrupt change in plans highlighted NASA's uncertainty about how to deal with the simultaneous issues that have forced the agency to lock three massive solar power arrays in place to prevent further damage and to keep the station stable.
A smooth mission turned tricky on Sunday when metal shavings were found in a 10-foot joint that rotates the massive solar arrays that produce the station's power.
Spacewalkers Scott Parazynski and Douglas Wheelock were scheduled to go take a closer look at the joint on Thursday and possibly try a repair.
But space station program manager Mike Suffredini said on Tuesday he would prefer that spacewalkers deal with the solar panel, which has a 2.5-foot-long rip that occurred while it was being unfurled on Tuesday.
Both are vexing problems because NASA does not know yet what caused them nor how they can be repaired.
The 110-foot-long solar panel was stowed in a truss that astronauts installed on Tuesday at the far end of the station.
Its twin panel was unfurled first and smoothly. The second one was extended about 95 feet when the astronauts guiding the deploy from the station spotted the damage.
Shuttle commander Pamela Melroy said in a crew press conference from space on Wednesday that the sun was blinding the astronauts as they monitored the deploy through a television camera and they did not see the damage occurring.
"The sun was shining directly into our camera," she said. "We can second-guess ourselves and there might have been some other things that we could have done, but I think we certainly aborted (the deploy) as soon as we saw something that wasn't right."
NASA has scheduled a December space shuttle launch to deliver Europe's Columbus laboratory, followed by the multi-segment Japanese Kibo laboratory starting with a February shuttle flight.
Suffredini said he would be reluctant to move ahead with expansion plans until the solar panel is repaired.
Station commander Peggy Whitson said in Wednesday's press conference she was confident it could be fixed.
". If there's a way to do it, we will figure out a smart way to come up with whatever work-around to make it happen," she said.
NASA has already added a day to the mission, with Discovery now due to return to Earth on November 7, but officials at Johnson Space Center another extension was possible.
NASA hopes to finish the space station, which is a project of 15 nations, by 2010 when the shuttle fleet is set to be retired.