Space Station Computers Still Down
The computers that control thrusters that keep the International Space Station in proper orientation are still not repaired as of this morning. Russian cosmonauts worked through the night but were only able to get one of three power feeds operational.
The Russians worked on the system through the night but only succeeded in getting one of three power channels to the station's computers operating before flight controllers told them to get some sleep, NASA flight director Holly Ridings said.
Valery Lyndin, spokesman for Russia's Mission Control outside Moscow, said Friday that support staff on the ground had so far been unable to pinpoint the source of the computer failure.
"The lives of the crew are not in danger," Lyndin stressed.
He said there were no plans to evacuate the space station. A NASA official also said the chance of abandoning the space station was remote.
The station's oxygen-regeneration and all basic life-support systems are functioning properly, but the orientation system was affected by the computer problems, Lyndin said.
The troubled computers, in the Russian segment, control thrusters that are fired to orient the station and its solar panels toward the sun for maximum energy production. Gyroscopes on the station's American segments are functioning, and the station is in a more-or-less proper position, he said.
"We've had computer failures before, and we have coped with the problem, but now the situation is much more complicated," cosmonaut Pavel Vinogradov said on 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."
The focus now appears to be on possible bad connections in the station power supplies.
"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 today."
The new solar arrays were connected by the Atlantis crew Monday. If the power feed from those arrays turns out to be the problem, the Russian section can still get power from other solar arrays.
Yesterday I mentioned the weird occurrence of a baby monitor in a Chicago suburb that is picking up NASA videos. I said then that NASA was too quick to dismiss that as not coming from the station. Because RF and EMF fields can do very weird things to electronics. Back when I was working at the first nuclear station I was at, there was a series of failures in the security computers. After beating their collectives heads against the walls for quite a while, the engineers trying to fix the problems finally traced it down. An improperly grounded twisted pair of wires was acting as an antenna inside one of the MUX boxes. It was blasting RF into the MUX and causing a whole bunch of weird stuff to happen in there. Once they fixed the connection, all the problems went away. I was not one of the people working on it, so that is as much as I know about that incident. But I remembered that when I had to update the meteorology tower - and my wiring had to go through those same MUX boxes. My connections were triple checked.
