CAPE CANAVERAL, Fla. (AP) - Spacewalking astronauts are making urgent repairs at the International Space Station.
Commander Peggy Whitson and Jack Fischer went out Tuesday morning, three days after a critical relay box abruptly stopped working.
Even though a second unit managed the data load just fine, NASA scrambled to put together a spacewalk in order to restore backup capability. The system is vital for operating the station's solar panels, radiators and robotic equipment.
The failed data-relay box was just installed in March.
While Whitson focuses on the 250-mile-high (400-kilometer-high) replacement job, Fischer will install a pair of wireless communication antennas that should have been hooked up earlier this month. That May 12 spacewalk was cut short by leaking station equipment.
Whitson now ties the record for most spacewalks by an American - 10.