MOSCOW - Mir's crew turned in early Friday to rest up for a rare Russian-American spacewalk aimed at finding punctures from the space station's damaging collision with a cargo ship.
Cleared by NASA to perform the mission just a day ahead of time, astronaut Michael Foale was set to float into open space with Mir commander Anatoly Solovyov at 4:55 a.m. Saturday (8:55 p.m. Friday EDT).
"This spacewalk is extremely important and puts a lot of responsibility on the crew," Yuri Glazkov, deputy chief of the cosmonauts training center, said Friday. "We wish them courage and composure."
The scheduled six-hour walk was to be the first chance for a direct inspection of the damaged hull since a remote-controlled supply ship rammed Mir in June, cutting into the station's power supply and heightening concerns about safety.
Much of the power was restored last month after a repair mission inside the ruptured Spektr module. The American-Russian team, besides looking for holes and videotaping damage, hoped to restore even more energy by realigning at least one of the module's three undamaged solar panels.
The patching of any holes will be saved for a future spacewalk. Even if the depressurized Spektr can't be fixed, the work is seen as valuable training for the international space station being launched next year.
As on every spacewalk, the main known safety hazards were sharp edges on the outside of the station that could rip the spacewalkers' suits. Any such tear in open space could be fatal.
The two were expecting a wake-up call before midnight to undergo thorough, last-minute medical checks and don their bulky Russian-made space suits - preparations taking as long as the spacewalk itself.
Foale was then to step out of the hatch to start what will be the second U.S.-Russian spacewalk ever. It was to be slightly longer and more challenging, NASA says, then the five-hour walk Jerry Linenger performed with Vasily Tsibliyev in April.
Loaded down with tools and seven flashlights, the two spacewalkers were to have enough air to last more than seven hours outside, but were told not to cut it too close.
It is the second spacewalk for the 40-year-old Foale, who made his first outside a U.S. shuttle in 1995. Solovyov, 49, holds the world record of more than 41 hours in open space on nine walks, not counting last month's "interior spacewalk" inside the airless Spektr.
On the ground, Russian space officials took a break Friday from a week of wrangling over who's to blame for the June 25 collision, uniting in a ceremony in honor of the ill-starred previous Mir crew.
Vasily Tsibliyev and Alexander Lazutkin wrapped up their three-week, post-flight rehabilitation and returned Friday to the cosmonaut training center outside Moscow, where they were met by an air force band, girls offering the traditional welcome of bread and salt, and officials' praise.
Keeping up a Soviet-era tradition, the crew laid flowers before a monument to Yuri Gagarin - the first man in space - and were welcomed by long speeches and cascades of flowers and other gifts, including plots of land for summer homes.
The cosmonauts again denied any wrongdoing, blaming the crash on a combination of factors. They praised Mir despite all its problems.
"The station was built very solidly and can receive many other crews," Tsibliyev said.