A US-Russian three-man crew Wednesday faced an unprecedented two-day delay in their docking with the International Space Station (ISS) after their Russian Soyuz spacecraft suffered a technical glitch on its approach in orbit.
The two Russian cosmonauts and American astronaut were to have docked with the ISS early Wednesday, just six hours after launch from Kazakhstan, but the problem means that the docking is now only planned on Friday.
The trio will now orbit the Earth 34 times before their rendezvous with the international space laboratory, instead of the fast track route of four orbits originally envisaged.
US-Russia space cooperation has continued undimmed despite the diplomatic standoff over Ukraine and the joint work is seen as one of the few true success stories in post Cold War ties.
Russians Alexander Skvortsov and Oleg Artemyev along with Steve Swanson of NASA had taken off from Russia’s Baikonur cosmodrome in Kazakhstan in a spectacular night-time launch that initially went off without a problem.
The issue arose once their Soyuz capsule was in orbit and a thruster failed to fire to assist its approach for docking with the ISS.
US space agency NASA said in a statement on its website that the Soyuz spacecraft “was unable to complete its third thruster burn to fine-tune its approach” to the orbiting space station.
The trio were using a fast-track approach to the ISS that Russia has been employing since 2013. After the problem, they are now using the traditional two-day longer approach that was employed up to 2012.
NASA said the three men were “in good spirits” despite the change of plan.
The Soyuz capsule later carried out two manoeuvres in orbit bringing it on the correct trajectory for the adapted two-day route to the ISS, a Roscosmos source told Interfax.
A third and final manoeuvre would be performed on Thursday to bring the craft to the right altitude for the eventual docking, the source added.
– ‘Mathematical problem?’ –
NASA said Russian flight controllers were reviewing data to work out why the third thruster burn did not occur as planned.
“Initial information indicates the problem may have been the spacecraft was not in the proper attitude, or orientation, for the burn,” NASA said.
The head of Russia’s space agency Roscosmos Oleg Ostapenko said the problem appeared to have been triggered by a hitch with the orientation system.
“The crew have taken off their space suits and are continuing their flight normally,” he said.
The head of the Russian rocket state firm Energia that supplies the Soyuz rocket that propels the craft into space however said that the origin of the problem was not yet clear.
“It could be mathematics, it could be a transmitter problem or that the engine choked. But most likely it was a mathematical problem,” said Vitaly Lopota, quoted by the Interfax news agency.
This would imply that ground scientists failed to work out the correct altitude in orbit for the thruster to fire to take the Soyuz to the ISS.
Roscosmos said the docking was now provisionally expected at 3:58 am Moscow time Friday (2358 GMT Thursday).
After the retirement of the US shuttle, NASA is for now wholly reliant on Russia for delivering astronauts to the space station on its tried-and-trusted Soyuz launch and capsule system.
– ‘Friends in the kitchen’ –
At the pre-flight news conference at Baikonur, senior astronauts Skvortsov and Swanson said they had decided to have dinners together on board the ISS “as an opportunity to come together as friends in the kitchen and look each other in the eye”.
Skvortsov is making his second space flight and Swanson, a veteran of two past shuttle missions, his third.
Artemyev meanwhile is making his first voyage to space. He took part in a 2009 experiment where volunteers were shut up in a capsule at a Moscow laboratory for 105 days to simulate the effects of a possible voyage to Mars.
After docking, the trio will bring the ISS crew up to six by joining incumbent crew Koichi Wakata of Japan, American Rick Mastracchio and Russian Mikhail Tyurin.