Spacewalking astronauts tackle urgent repair job

CAPE CANAVERAL, Fla. (AP) — Space station astronauts are taking a spacewalk to replace a dead computer and get their orbiting home back up to full strength.

The two Americans on board, Rick Mastracchio (muh-STRAK'-ee-oh) and Steven Swanson, stepped out Wednesday for the urgent repair job.

The computer is a critical backup outside the International Space Station that failed nearly two weeks ago. The prime computer has been working fine, but NASA wanted to install a fresh spare as soon as possible.

Mission Control waited until after the arrival of a capsule full of fresh supplies on Sunday

The spare computer is a compact 50-pound box. Engineers don't know why the original failed. The astronauts will check for any damage.

It's expected to be a short spacewalk, involving just three bolts.