By ARNEWS and NASANovember 18, 2008
WASHINGTON (Army News Service, Nov. 14, 2008) -- Army Lt. Col. Robert S. Kimbrough blasted off in the space shuttle Endeavour Friday evening on a scheduled 15-day mission to the International Space Station.
Kimbrough is a mission specialist on STS-126 and is scheduled to participate in space walks to service the station's solar alpha rotary joints, to ensure adequate solar power can be provided to the expanding space station.
STS-126 has been planned as the mission that will give the International Space Station the ability to support twice the crew currently living there. Endeavour has a reusable logistics module that holds additional crew quarters, additional exercise equipment, equipment for the regenerative life support system and other supplies for the space station.
"It's the most jam-packed logistics module we have ever carried up there," STS-126 Commander Chris Ferguson said. "We're taking a three-bedroom, one-bathroom house and turning it into a five-bedroom, two-bathroom house with a gym."
STS-126 will also ensure adequate power for all the new equipment and the future space station crew that will eventaully expand from three to six. Four days of space-walking are scheduled to fix issues with the station's solar alpha rotary joints.
The solar alpha rotary joints are two 10-foot-wide, wagon-wheel-shaped joints on the station's truss that allow the electricity-generating solar arrays to rotate so that they're always getting as much sun as possible. Flight controllers on the ground noticed a year ago that it was taking more power than normal to rotate the joint on the station's starboard side, and it was vibrating more than it should.
Previous spacewalks to inspect the joint narrowed the more than 100 possible causes of problems down to one: insufficient lubrication. Without enough lubrication, the trundle bearing assemblies that hold the two halves of the joint together, and allow one side to rotate while the other stays still, were pressing too hard against one side of the joint, according to NASA officials. They said this added pressure damaged the steel of the joint's "wheel," which the bearings roll against, and left metal filings that could cause more damage.
So three astronauts will spend the majority of their four spacewalks working to clean metal shavings off of the surface of the solar alpha rotary joint, then lubricating it and replacing the trundle bearing assemblies.
Back inside, the Endeavor crew will spend time unpacking new crew quarters for the space station, a new toilet, a new kitchen, a new refrigerator and new exercise equipment , along with science experiments.
STS-126 is the 27th shuttle mission to the International Space Station. Sandra H. Magnus of STS-126 will remain on the space station, replacing Expedition 17/18 Flight Engineer Gregory E. Chamitoff, who returns to earth with the shuttle crew.