Washington: A piece of space debris narrowly missed the International Space Station on Tuesday in a rare incident that forced the six-member crew to scramble to their rescue craft, space agency officials said.
The object was projected to miss the orbiting lab by just 250 meters (820 feet), NASA said, and the crew moved to shelter 18 minutes before it was expected to pass.
"There was a piece of space debris that came near the station and we didn`t find out about it in time to perform a debris avoidance maneuver so we had the crew shelter in place in their Soyuz vehicles," spokeswoman Stephanie Schierholz of the US space agency said.
The six astronauts climbed into the two Soyuz craft at 7:50 am Eastern time (1150 GMT), and the expected time of closest approach to the object was 8:08," Schierholz said.
"They spent about half an hour in their Soyuz," she said. "They are back to their regular day."
The event was unusual but not unheard of, she added. A similar event on March 12, 2009 forced the crew of the space station to seek temporary shelter when a piece of space debris approached.
"We monitor space debris pretty closely so this is not, sort of, out of the realm of what we know can happen," Schierholz said.
"But obviously we are concerned about the safety of the crew so that is why we had them take shelter."
A Russian space official also said by telephone that such incidents had occurred in the past and did not represent an emergency.
"This is not an emergency operation. They have standing instructions to that effect," the spokeswoman told AFP.
Space officials said the crew knew what to do if the orbiter could not be maneuvered out of the way in time.
The ISS is currently manned by three Russians and two Americans as well as a Japanese astronaut.
The commander of the current mission to the ISS, Expedition 28, is Andrey Borisenko. The flight engineers are Alexander Samokutyaev, Mike Fossum, Satoshi Furukawa, Ron Garan and Sergei Volkov.
The Soyuz TMA-20 undocked at the orbiting lab on May 23 and the three newest crew members arrived June 9 on the Soyuz TMA-02M. The crew usually stays for six-month stretches aboard the space station.
The ISS was built up from the first module launched by Russia in 1998 and is now orbiting 350 kilometers (220 miles) above Earth.
The US space shuttle program, which is set to end later this year after the July 8 launch of Atlantis on its final mission to the space lab, helped construct the international research laboratory.