Space Station Computer Failure, Astronauts Scramble

June 14, 2007 — -- An unprecedented computer failure in the Russian segment of the International Space Station has engineers at space centers in Houston and Russia scrambling to solve the problem before the Space Shuttle Atlantis undocks on June 19.

This morning the computers were beginning to send signals to the ground — not a fix, but the first good news since the problem appeared Tuesday.

The station's commander, Russian cosmonaut Fyodor Yurchikhin, stayed up all night to work with flight controllers in Russia's Mission Control to repair the problem.

All three computers for command and control, plus three guidance computers, which provided triple redundancy for vital space station functions, failed; astronauts and ground controllers made repeated attempts to force them to reboot.

There is speculation that new solar arrays, which were installed earlier this week by the visiting shuttle crew, may have triggered the computer shutdowns. These computers stabilize the space station on orbit. They also control the systems that generate oxygen for the crew and scrub deadly carbon dioxide from the atmosphere inside the space station.

Without the guidance and control computers, rocket thrusters cannot be used to adjust the space station's orientation. Much of the time, the station is stabilized by large gyroscopes, but the gyros and thrusters have to work in tandem.

In the meantime, Atlantis' thrusters were being used, but the shuttle was supposed to leave the space station Tuesday.

Program Manager Mike Suffredini said he had never seen a failure like this before, and it was baffling to him. What would he do if the computers did not return to full operation?

"If we are in that position, we have an option to depart. We always have an option to do that," he said.

Suffredini said he was confident the problem could be solved. "It's not an urgent situation, but clearly it needs to be resolved before our shuttle friends leave."

A Soyuz "lifeboat" is always docked to the space station, so if the space station crew must abandon ship, it has a way home.

Mission Management Team Chairman John Shannon says his team was looking at ways to keep the space shuttle docked to the station for an extra day or two, if necessary, by conserving power on the shuttle. Atlantis cannot stay docked to the space station indefinitely, though, and managers like to preserve two contingency days in case of bad weather at landing sites in Florida, California and New Mexico.