Station crew has close call with space junk

— -- The three crewmembers of the International Space Station had to take refuge Thursday in an escape pod while a piece of space junk big enough to punch a hole in the station hurtled dangerously nearby.

The crew spent 11 minutes in the Russian spaceship called the Soyuz. The capsule could have carried the crew — Americans Mike Fincke and Sandra Magnus and Russian Yury Lonchakov — to Earth if needed.

Any hole in the station's walls could allow the oxygen to leak out, depriving the crew of air. The piece of debris was more than 10 times bigger than the smallest object that can penetrate the station's shielding, said Gene Stansbery, orbital debris program manager at NASA's Johnson Space Center. The threat was a 5-inch long piece of debris speeding some 22,000 mph relative to the orbiting lab, he said.

The debris was part of a U.S. rocket that launched in 1993, Stansbery said. Objects break down in space because of collisions and temperature swings, creating more and smaller pieces of debris. The station's walls are clad with armor in case of collisions with space junk, but the piece of rocket was bigger than the station could withstand.

"Mr. Dempsey was sweating bullets," astronaut Clay Anderson in Mission Control told the crew, referring to station flight director Bob Dempsey.

"We were ready in case of a worst-case scenario, but thank goodness it didn't happen," Fincke replied.

The evacuation of the station came as yet another headache for NASA in a difficult week. A fuel leak forced the agency to call off Wednesday's launch of space shuttle Discovery, which had already been delayed by a month. The shuttle is scheduled to blast off Sunday.

A Sunday launch will still require Discovery's mission to be cut short, to prevent an overlap with a new crew's arrival at the station. If Discovery doesn't launch by Wednesday, it would be delayed until April. That kind of postponement would in turn delay a high-profile mission to fix the Hubble Space Telescope.