posted March 12, 2009 11:41 AM               

Station Crew Takes Precautionary Measures Due to Space Debris

International Space Station Expedition 18 crew members are taking precautionary measures due to space debris that has been determined to be within the range where a collision is possible. News of the close approach came too late for flight controllers to coordinate an avoidance maneuver. A portion of a spent satellite motor is within the distance of the station's debris avoidance maneuver requirement "box."

Crew members are entering their Soyuz TMA-13 capsule and soft-locking the hatches, in case the debris should affect the space station and they are required to undock. The closure of the hatches ensures the safety of the crew and the ability to quickly depart the station in the unlikely event the debris collided with the station causing a depressurization.

The time of closest approach of the debris to the station is 12:39 p.m. EDT. Once the object is clear of the station, the crew will exit the Soyuz and reopen the hatches.

The crew will be in the Soyuz from 12:35-12:45 p.m. EDT. They will remain in the Soyuz until the debris risk has passed. Moving the crew into the Soyuz is a precaution, as the probability of impact is low. The crew is currently putting space station into an unmanned configuration, including several interior station hatches.

posted March 12, 2009 11:43 AM               

A NASA source said the debris in question was listed as "PAM-D" debris, an acronym implying it was a spent payload assist module solid-fuel motor used to boost payloads to higher orbits. It was not immediately clear if that was, in fact, what the debris might be.

posted March 12, 2009 11:47 AM               

NASA: Space Station Debris Threat Passes

The debris threat to the International Space Station has passed. The crew was notified of the all clear at 12:45 p.m. EDT. The crew will depart the Soyuz and return the station to normal operations.

posted March 12, 2009 12:17 PM               

...a small weight attached to a 1-meter cable which unwinds from the spinning PAM-D stage and which departing angular momentum is used to tumble the stage to make sure that residual thrust doesn't cause it to hit the payload.