Unplanned Spacewalk Scheduled as Early as Monday

NASA Astronauts to Conduct Spacewalk as Early as Monday, Dec. 21

"Expedition 46 Commander Scott Kelly and Flight Engineer Tim Kopra of NASA are preparing for a previously unscheduled spacewalk outside the International Space Station on either Monday, Dec. 21, or Tuesday, Dec. 22. The pair will move the station's mobile transporter rail car so it can be latched in place ahead of the Wednesday, Dec. 23 docking of a Russian cargo resupply spacecraft.

The mobile transporter -- used to position the station's robotic Canadarm2 -- stalled on Dec. 16, just four inches (10 centimeters) from where it began its move, while flight controllers in the Mission Control Center at NASA's Johnson Space Center in Houston were attempting to reposition it robotically. The cause of the stall still is being evaluated."