Russia blames 'software failure' for misfired engines that shook ISS

Washington/Moscow, July 31 : Russian space agency Roscosmos has blamed a short-term software failure which led to erroneous engine firings by its Nauka Multipurpose Laboratory Module, docked with the International Space Station (ISS), shifting the ISS off its normal position.

On Thursday, the Russian module's thrusters unexpectedly fired hours after docking, causing the Nauka module to think it was supposed to back away from the ISS.

The space station was shoved 45 degrees off track once Nauka's thrusters started unexpected firings.

"Due to a short-term software failure, a direct command was mistakenly implemented to turn on the module's engines for withdrawal, which led to some modification of the orientation of the complex as a whole," Vladimir Solovyov, the flight director of the space station's Russian segment, said in a statement on Friday.

NASA had said it lost control of the station's positioning minutes later, but it was repositioned back to normal.

According to Solovyov, during the final rendezvous, slight fluctuations were noticed, which were eliminated by the docking system.

"At the moment, the station is in its normal orientation, all the ISS and the multipurpose laboratory module systems are operating normally. A reliable internal power and command interface was created, as well as a power supply interface that connected the module to the station," he added.

Nauka, which means 'science' in Russian, is a multipurpose module designed to carry cargo and humans to space.

The crew was now busy balancing the pressure in the Nauka module.

"This is a rather lengthy procedure, because the total volume of the module is about 70 cubic metres. The crew will open the hatches, enter the module, turn on the necessary means of purifying the atmosphere and begin normal regular work," said Solovyov.