Russia on Wednesday lost the ability to send basic commands to most of its satellites and segment of the International Space Station following a vital cable failure near Moscow.
The Roscosmos space agency attributed the embarrassing malfunction to basic road repair work near the the sprawling Korolyov mission control centre that sits within sight of one of Russia's most heavily-used highways.
Industry sources said the problem may take at least 48 hours to fix and could therefore delay the November 19 return of three ISS members who are completing their four-month mission on board the floating international space lab.
"Our specialists lack the ability to control the civilian satellites or send commands to the Russian segment of the ISS," RIA Novosti quoted an unidentified Russian space official as saying.
"They can see the crew and can talk to them, but they cannot send any commands to the Russian segments."
Russia has suffered a string of failed satellite launches and rocket losses in the past two years that prompted reshuffles at the very top of the country's once-proud space industry.
But the agency has struggled to reform due to chronic underfunding and alleged corruption as well as a long-term inability to replace retiring Soviet-era specialists with fresh talent.
The main subsidiary of Roscosmos is currently the subject of a 6.5 billion ruble ($200 million) embezzlement probe that has fanned speculation over possible new sackings at the top of Russian space command.
Space officials were quick to put a brave face on the latest public relations disaster by stressing that both the satellites and the space station remained functional even while being out of control.
"The cable tear occurred during the road repair work... and has not impacted the operation of Russian satellites or the International Space Station," Roscosmos spokesman Alexei Kuznetsov told Interfax.
"We have rerouted our ground-based control facilities and the situation is under control," he said without providing further details.
Another source said that Russia's military satellites were unaffected by the breakdown and continued to function as before.
"Communications with the military satellites continue as always," the source told RIA Novosti.
The possibility that the cable may take days to fix could delay the return of three astronauts—including current ISS commander Sunita Williams of NASA and Akihiko Hoshide of Japan—who had been away from Earth since July.
"This communications cable break tear could abort our ability to relay the undocking command to the Soyuz capsule," the unnamed space industry source told RIA Novosti.
Roscosmos spokesman Kuznetsov said only that the November 19 return date remained the official one "at this time".
It appeared that most of the immediate problems with the ISS had been averted because the orbiter was being controlled by US officials at the time of the break.
Russian officials said the station was flying over a segment of Earth within reach of the telemetry stations of NASA on Wednesday afternoon Moscow time when the accident occurred.
But Roscosmos is due to take command of the ISS on Wednesday at 2230 GMT.
"We hope that the cable will be repaired by then," Gennady Raikunov of the scientific institute in charge of Russia's space communications told Interfax.
Interfax said that several vehicles from the Akado company that operates the communications cable had located the site of the tear about six hours after the incident.
The news agency added that the experts refused to speak to the press as they began assessing the extent of the damage on the ground.
NASA also issued no immediate comment on the incident or the possibility of Williams' delayed return.
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