Nasa reported major progress on glitches in a critical computer system on the International Space Station on Friday as astronauts repaired insulation damage to the space shuttle Atlantis during a spacewalk.
Four of the six boxes or ”lanes” that comprise the computer were up and running, raising hopes they would not break down again.
”They do appear to be working,” Nasa space-station programme manager Mike Suffredini told a press briefing late on Friday.
He said the computers, which are in the Russian segment of the $100-billion space station, would be left up and running through the night, but controllers would need 24 to 48 hours to determine if they were reliable.
He said the Russians had bypassed circuits on the computers that appeared to be causing the problems. The space shuttle will likely bring the two that are still malfunctioning back to Earth with it and the Russians will then bring replacements up on a later mission of their own.
Friday’s news was by far the most encouraging since the computers crashed on Wednesday.
The computers control the station’s positioning in space so it can draw power from the sun, maintain proper temperature and position antennas for communicating with ground controllers.
The German-built computers also control critical life-support equipment, such as the oxygen generators and scrubbers that remove deadly carbon dioxide. Those machines can also be manually controlled.
The computer failure, if not corrected, could have forced temporary evacuation of the space station. The computer crash was not considered life-threatening to either the station or shuttle crews.
Successful spacewalk
Nasa astronauts James Reilly and John ”Danny” Olivas completed the third spacewalk since Atlantis arrived at the space station on Sunday. It lasted almost eight hours.
The spacewalkers’ most crucial task was repairing a protruding piece of insulation on an engine pod near the rear of the spaceship. The corner flap of a blanket tore loose during Atlantis‘s climb to orbit last Friday.
While the exposed gap is not believed to pose a Columbia-like heat-shield breach, managers said repairing the damage would protect the shuttle’s underlying structure from weakening during the scorching plunge through the atmosphere.
A breach in shuttle Columbia‘s wing, caused by a debris impact during launch, triggered the spaceship’s break-up over Texas on February 1 2003. All seven astronauts aboard died.
The astronauts also successfully helped retract a bulky solar panel. The productive spacewalk further saw the installation of a hydrogen vent on the space station. The vent is for a new oxygen-generation system.
A milestone on this mission was to be reached at 5.47am GMT on Saturday when Sunita Williams would break the record for the most time spent in space by a woman. She would have spent 188 days and fours hours in space, eclipsing the record set by fellow American Shannon Lucid.
Williams travelled to the space station on the previous shuttle mission in December and is scheduled to return with the shuttle to Earth next week. — Reuters
Additional reporting by Irene Klotz in Cape Canaveral