WASHINGTON – A fragment of space junk, just a third of an inch wide, threatened to collide Thursday with the International Space Station, briefly forcing three astronauts to evacuate the station and take refuge in an attached Russian spacecraft that serves as an emergency lifeboat.

The debris missed, and the astronauts quickly returned to the station after just 11 minutes aboard the Soyuz spacecraft. But the unusual event offered a reminder that astronauts and spacecraft are increasingly playing a deadly game of space-debris dodge ball in orbit.

NASA was notified late Wednesday that, at 12:39 p.m. EDT Thursday, the object, a piece of a motor used to launch a satellite, would pass about three miles from the space station. But orbital trajectories are imprecise, and this rated as a close call, or “conjunction.”

Typically when there is a possible collision with space junk, the flight team at NASA will maneuver the space station, steering it out of harm’s way. But the notification from the military about this particular object came too late to execute an avoidance maneuver.

“From what I can tell, (the piece of debris) was having a very erratic orbit, and that is what contributed to us getting the very late notice,” said NASA spokeswoman Nicole Cloutier.

She said the astronauts were informed of the decision to evacuate at 11:40 a.m. EDT. During the evacuation, NASA stated on its Web site that there was little chance of a collision: “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.”