5p 11/22 Update: At halfway point, 2 bearings replaced; crew ahead of schedule

=================================

CBS NEWS STS-126 STATUS REPORT: 52
Posted: 5:00 PM, 11/22/08

By William Harwood
CBS News Space Analyst

Changes and additions:

   SR-50 (11/22/08): Spacewalk begins; urine processor troubleshooting continues
   SR-51 (11/22/08): Cleaning goes smoothly in initial stages of EVA
   SR-52 (11/22/08): Two trundle bearings installed; astronauts ahead of schedule at halfway point

=================================

05:00 PM, 11/22/08, Update: Two trundle bearings installed; astronauts ahead of schedule at halfway point

Halfway through a planned seven-hour spacewalk, astronauts Heidemarie Stefanyshyn-Piper and Stephen Bowen are still running about a half hour ahead of schedule cleaning and lubricating the space station's right-side solar array rotary joint. Two of six new trundle bearing assemblies have been installed, Bowen is working to install a third and Stefanyshyn-Piper is cleaning a different section of the joint's 10-foot-wide drive gear before installing a fourth.

At the Johnson Space Center in Houston, meanwhile, engineers are still studying data on the performance of newly installed urine recycling system hardware. The centrifuge motor in the processor's vacuum distillation unit has been re-started twice today, but it currently is off line pending additional troubleshooting to understand what is causing the motor to slow down and draw more current than expected.

=================================

Quick-Launch Web Links:

CBS News STS-126 Status Reports:
http://www.cbsnews.com/network/news/space/current.html

CBS News STS-126 Quick-Look Page:
http://www.cbsnews.com/network/news/space/currentglance.html

NASA ISS Expeditions Page:
http://www.nasa.gov/mission_pages/station/expeditions/index.html

NASA Shuttle Web: http://spaceflight.nasa.gov/shuttle/index.html
NASA Station Web: http://spaceflight.nasa.gov/station/index.html
Spaceflight Now: http://spaceflightnow.com/index.html
GoogleSatTrack: http://www.lizard-tail.com/isana/tracking/

=================================