Russia May Move Up Cargo Flight To Bring New Parts

The combined Expedition 15 and STS-117 crews spent a second day Friday attempting to reboot problematic computer systems onboard the International Space Station, as controllers on the ground mulled over possible options -- including moving up a planned resupply flight to bring up needed parts, or abandoning the station.

The latter remains a remote possibility, though engineers must solve a series of cascading computer failures before they can guarantee the station will remain manned. Those failed computers, which first experienced problems Wednesday, control the station's orientation in orbit... and the station's Elektron oxygen-generating system.

For the moment, the docked space shuttle Atlantis may use its thrusters to help maintain the station's position, reports The Associated Press. And the station has enough breathable air for 90 days, according to Russian space officials.

"We have enough time to calmly deal with the situation," said Russian Mission Control chief Vladimir Solovyov. "There is no need to rush."

NASA instructed astronauts Thursday to shut down non-critical electronics onboard Atlantis -- including cameras, laptop computers and lighting equipment -- to conserve energy, in case officials determine the shuttle should remain docked to the station for another day to help with the situation.

As ANN reported, NASA already extended Atlantis' mission by two days earlier this week, to provide time for an extra spacewalk to repair a thermal blanket that pulled free from one of the shuttle's orbiting maneuvering system pods during its June 8 launch.

If engineers and cosmonauts aren't able to repair the Russian-made computers, the station's orbit could drop to as low as 200 miles above Earth -- roughly 37 miles lower than its current orientation. Solovyov said this isn't an alarming amount -- but the higher the orbit, the less air there is to create atmospheric drag to pull the station even lower.

For the moment, crews onboard the ISS are split along national lines -- with Russian cosmonauts working to solve the computer problems, and NASA astronauts continuing to perform construction work and spacewalks.

"We've had computer failures before, and we have coped with the problem, but now the situation is much more complicated," cosmonaut Pavel Vinogradov told NTV television. "We have the shuttle docked to the station, and active work is going on at the station -- the Americans' space walk. We must maintain the station's orientation."

During a third spacewalk, scheduled to begin Friday afternoon, STS-117 Mission Specialists Jim Reilly and Danny Olivas will tackle separate tasks when they begin the mission's third spacewalk. Olivas will be tasked with repairing the thermal blanket on Atlantis -- by first tucking it back into position, then stapling it down on the left orbital maneuvering system pod.

Meanwhile, Reilly will install a hydrogen vent on the International Space Station's Destiny Laboratory. The vent is for a new oxygen generation system.

The duo will then go to the top of the station’s Port (P6) truss to assist in the retraction of a solar array. Over a two-day period the crew has folded most of the array bays. A future shuttle crew will relocate the P6 to the end of the Port 5 truss.

Scientists are looking at the possibility earlier work on the station may have led to the current computer problem. Nikolai Sevastyanov, head of Russia's RKK Energiya, said the problem began with a spike in static electricity while cables were being hooked up between the station and the new solar arrays installed earlier this week. That theory is supported by NASA engineers, as well.

"A power line has a certain magnetic field around it, and that can affect systems near it," said Mike Suffredini, NASA's space station program manager. "This is the leading theory."

FMI: www.nasa.gov