The station's robotic arm, Canadarm2, is in position with cameras to videotape the condition of a solar array gear this weekend. The video inspection of the Solar Alpha Rotary Joint (SARJ) as it rotates will assist engineers on the ground as they formulate a plan on future repairs. The starboard side SARJ will rotate 360 degrees twice, once on Saturday and once on Sunday.

Commander Peggy Whitson and Flight Engineer Dan Tani were at the robotics workstation as the Canadarm2 walked off the Harmony Node to the Mobile Transporter (MT) on the station's truss structure. The MT then slowly moved the robotic arm near the Starboard 3 truss where it was maneuvered into position for this weekend's inspection.

Earlier in the week, Flight Engineer Yuri Malenchenko tested an automated rendezvous system on the Russian side of the International Space Station. Russian ground specialists will review the downlinked data as they prepare for the upcoming launch and docking of Europe's new cargo delivery vehicle, the Automated Transfer Vehicle.

Station crew members continue packing a docked Progress 27 cargo craft with discarded items. The Progress 27 will undock, deorbit and burn up in Earth's atmosphere over the Pacific Ocean on Feb. 4. A Progress 28 resupply vehicle will arrive at the Pirs docking compartment three days later.

Source http://www.nasa.gov/mission_pages/station/main/index.html