Cleanup mission accomplished during Endeavour spacewalk

''Finally,'' astronaut Stephen Bowen said after a spacewalk yesterday outside the International Space Station. Yesterday's spacewalk was the fourth for shuttle Endeavour's astronauts. (NASA TV via Associated Press)

CAPE CANAVERAL, Fla. - Astronauts carried out one last spacewalk yesterday to finish an unprecedented clean and lube job that they began a week ago at the international space station.

Spacewalker Stephen Bowen wrapped up work on a jammed solar-wing rotary joint as his partner, Shane Kimbrough, squirted some extra grease as a precaution on another joint that is working fine.

When the repairs to the gummed-up joint were deemed officially complete, Mission Control radioed up its applause.

"Finally," Bowen exclaimed. "Thanks for your work," replied Mission Control, erupting in laughter.

Just before the spacewalk began, NASA added a 16th day to space shuttle Endeavour's mission. Managers wanted to give the astronauts more time to fix a machine that's supposed to turn urine into drinking water and more repair work was on tap for the fifth day in a row.

The $154 million recycling equipment was delivered by Endeavour, along with other home makeover items needed to expand the space station crew to six next year.

Yesterday's spacewalk was the fourth for Endeavour's astronauts. Not everything got done during the last one - one more bearing needed to be replaced in the clogged joint - so Bowen and Kimbrough have to take care of that, too.

The rotary joint on the right side of the space station hasn't worked properly for more than a year, preventing the solar wings on that side from pointing automatically toward the sun. Grinding parts left the joint full of metal grit.

Almost all the greasy mess was cleaned up during the first three spacewalks and new bearings were put in. Bowen finished the job yesterday, paving the way for a test of the newly repaired joint today. Regardless of the outcome, more spacewalks are planned on later missions for a better, longer-term fix.

An identical joint on the left side of the orbiting complex has worked perfectly, but NASA wanted the spacewalkers to grease it up to ensure its longevity. Once they opened up this joint, the astronauts noticed wear on some parts.

The dialogue between the spacewalkers and the astronauts inside was technical and full of numbers denoting the various panels on the joints. "Too many numbers," one of the spacewalkers grumbled.

As they have before, the spacewalkers had to share grease guns 225 miles up. There was one less tool kit after a sack full of grease guns and other items floated away on the first spacewalk last Tuesday.

The extra day in space for Endeavour now means that the two crews will celebrate Thanksgiving together and not part company until Friday. Endeavour's touchdown is now scheduled for Sunday.