2 computers systems on space station fail

WASHINGTON -- Russian and NASA engineers worked into the evening yesterday to figure out why two computer systems essential to the operation of the international space station crashed, and the agency began making contingency plans that include potentially abandoning the $100 billion facility if the crews should fail.

Officials with the National Aeronautics and Space Administration said that the situation appeared to be improving and that some communication had been restored to the Russian computer system.

But NASA's space operations chief, William Gerstenmaier, said the failure is complicated and will probably take days to fix.

"At this point, we don't know the root cause of the problem," he said. "Fortunately, we have a lot of flexibility in terms of timing."

The computer systems began to have problems the day after new solar panels were deployed, creating an additional source of electric power. The computer systems control thrusters that keep the station properly oriented. They are also used to control the oxygen-production and carbon dioxide scrubbing systems for the air the astronauts breathe.

The three-person station crew was joined this week by a seven-member team on the space shuttle Atlantis. NASA officials said they are in no danger.

Michael Suffredini, manager of the space station program at Johnson Space Center in Houston, said intensive work to restore the computer functions began yesterday morning, when the station's orbit brought it near its Russian control station, and continued through the day.

He said the computers -- which were made in Germany by Daimler-Benz and donated by the European Space Agency -- may be especially sensitive to "noise," or variations in an electric signal that can cause static.

That noise, he said, may have started after the new array of solar panels were connected.

Suffredini said he expected the computer problem to be resolved. "I'm not thinking this is something we will not recover from," he said.

As a precaution, he said, NASA is looking into options to further extend the shuttle's stay, because its power and thrusters could be used to keep the station properly situated, with the solar panels facing the sun.

Mission Control had decided to extend the 11-day mission by two days to allow time to repair a damaged portion of the shuttle's thermal insulation.

Returning the station's crew to earth -- most likely aboard the emergency Soyuz spacecraft docked at the station -- would be the worst-case scenario.

The Russian computers appeared to be stuck in a rebooting cycle, and their failure led to a number of false fire alarms.

While the astronauts continued their troubleshooting, NASA officials said, nonessential power use was being restricted.

Gerstenmaier acknowledged that the computer program was serious, but he said the crew members and ground control were working out solutions.

"I think we're stable," Gerstenmaier said. "In my world, this is space station operations."