June 17, 2007 — Two U.S. astronauts planned to make the fourth spacewalk in a week on Sunday, as critical Russian computers which had failed last week in the International Space Station continued their recovery to normal operations.
Four of the six computer processors were operating, while the remaining two were turned on and then flipped back off to be "in cold standby mode" so that they could be used if needed, said flight director Holly Ridings.
"We can report that things are still improving," Ridings said.
With the exception of an oxygen generator, all of the systems that were powered down when the computers failed were back running.
The final benchmark for deciding whether the computers work properly and whether space shuttle Atlantis needs to stay docked an extra day to continue offering help will be a test of the station's thrusters on Monday. Atlantis is set to undock on Tuesday.
"We'll make sure the computers are still talking to the thrusters and prove to ourselves that we've got everything we need in order to undock safely," Ridings said.
The top priority for the spacewalkers, Patrick Forrester and Steven Swanson, is to activate a rotating joint on the outpost's newest segment, allowing a new pair of solar wings to track the sun.
They also planned to install a camera, a debris shield and a computer network cable between the United States and Russian sides of the space station during the planned 6 1/2-hour spacewalk.
