NASA has rescheduled a fourth spacewalk from Thursday to Friday after a rip was discovered in a solar panel on the International Space Station Tuesday. The mission was originally scheduled for Thursday.
A solar panel ripped while it was extended after being reinstalled on the space station Tuesday. The array, part of the P6 truss that was moved from one side of the space station to another, has a 2½-foot tear in it. During the fourth spacewalk, which could be moved from Thursday to Friday, astronauts will attempt to repair the damage.
Engineers and analysts worked through the night to figure out how the panel was torn and how it can be fixed.
The current space shuttle mission, STS 120, may also be extended another couple of days as a result of the problems.
When space shuttle Cmdr. Pam Melroy noticed the rip, she immediately aborted the deployment. "It looks like the damage appeared fairly suddenly," Melroy told Mission Control.
If NASA doesn't figure out a way to fix the torn array, it has implications for future missions. Space shuttles, Soyuz capsules and Progress supply ships will not be able to dock at the space station, because the arrays aren't positioned properly.
The mission management team is trying to determine which problem is the most important priority for the next space walk.
The plan now is to have spacewalking astronauts take a thorough look at the solar array rotating joint on the starboard side of the space station. A large ball joint, used to point solar panels on the station, seems to be rubbing up against something, using more power than normal, and vibrating the solar array.
Astronaut Dan Tani found metal shavings inside the joint when he opened it up during a spacewalk on Sunday.
Is this a problem for NASA? Space station program manager Mike Suffredini says yes.
The solar array is operating at 97 percent capacity, but the concern is about future damage if it is not fixed.
Flight director Derek Hassman said they were on the way to having a 95 percent good day, until the solar array ripped. Astronauts Scott Parazynski and Doug Wheelock completed a demanding seven-hour spacewalk to finish installing the truss and inspect another solar array part for damage.