By DPA
Washington/Moscow : After days of uncertainty about the six computers that keep the orbiting space station in place, Russian cosmonauts used a jumper cable bypass to get four of them working again, NASA officials said.
In another good bit of news, US astronauts visiting with the docked Atlantis shuttle were successful in stapling fast an errant tear protruding from the spacecraft's thermal blanket. The tear needed to be repaired before the shuttle heads back to earth next week.
Spacewalker Danny Olivas "used a medical stapler to secure it to adjacent blankets on Atlantis' left orbital manoeuvring system pod", NASA said.
The computer and shuttle glitches underlined the risks of spaceflight and complicated the main task of the mission – unfurling yet another set of solar panels to increase electric generation on the station.
Indian American Sunita Williams and six other astronauts were slated to leave Tuesday on board Atlantis, but NASA managers were considering adding a day at the space station to figure out the problem with the Russian computers.
The Russian computers began experiencing problems soon after the solar panels were deployed Wednesday. The problems were thought to be due to static or noise caused by variations in electric signals – similar to the effect a mobile phone receiving a call can have on a television or computer.
Physical damage had been done to the power units of the computers, a NASA official said in broadcast remarks, but nobody at NASA "thinks this vehicle is at risk of being lost, not even remotely", he added.
Russian space station commander Fyodor Yurchikhin and flight engineer Oleg Kotov went through every cable looking for electrical interference, then found a faulty secondary power switch that they bridged with the jumper cable, according to NASA.
Meanwhile, Russian and US flight controllers and engineers were also exploring alternatives to keeping the station in its proper altitude and tilt for maximum solar collection and energy supply.
The ISS is not endangered as long as a gyroscope in the US part of the station can hold it on course. If that were also to fail, the Atlantis could provide stabilisation, officials said.
Russian officials Friday said they were considering bumping up the launch date of a spacecraft to bring new energy sources for the failing computers, which are critical to the operation of the ISS, though US space agency NASA said the astronauts were safe and there was no need to evacuate.
US astronauts Olivas and James Reilly entered the open cosmos for more than six-hours to fix the thermal blanket and install a valve connected to the station's oxygen system and help retract an old solar panel.
They also inspected the cable they connected to a new set of solar panels installed during earlier spacewalks this week, which was a suspect in the computer problems.
While the US computers have not been affected, Sevastyanov said static electricity from the panels had knocked out the Russian computers' power.
Energia, the firm that produces Rusdsia's space rockets, said it had contacted NASA to request the space shuttle Atlantis bring back one of the computers for analysis when it leaves the ISS next week.
The problems have concerned NASA enough to take energy saving measures on the Atlantis so that it could stay in space another extra day if it is needed to stabilise the ISS. The robot arm and other non-necessary systems were turned off.