Three crewmembers aboard the International Space Station will remain in orbit for more than two weeks longer than planned while Russia investigates a launch accident that destroyed an unmanned cargo ship last week. Russia has also delayed its next manned mission to the ISS by more than a month, officials said yesterday.
Space station commander Andrey Borisenko, cosmonaut Alexander Samokutyayev and NASA astronaut Ronald Garan had been set to return to Earth on September 8, leaving three crewmates to staff the outpost until replacements arrived around two weeks later.
But the Russian Soyuz rockets used to fly crews to the station have a nearly identical upper-stage motor as the ones used on Russian cargo ships, the last of which failed to reach orbit following launch last Wednesday.
The Progress cargo ship burned up in the atmosphere and the debris crashed in Siberia. The crash marked the first time the Progress cargo carrier had been lost on a mission since it was first fitted on a Soyuz for its maiden flight in 1978.
Russian space agency Roscosmos is now conducting a check of all its rockets after the disaster, which followed three other failed launches of satellites since December in an unprecedented catalogue of accidents.
Crew flights to the space station have been suspended until the cause of the accident is determined. Yesterday Alexei Krasnov, Russia’s manned spaceflight programme director told RIA Novosita that the next manned mission to the ISS will only take place in late October or early November and not September 22 as planned.
Krasnov said the three crewmembers would only return on September 16, using one of two Soyuz spacecraft docked at the ISS.
“If for some reason we fail to send up the next crew by the end of November, we will have to study all the available options, including one of leaving the station unmanned,” Russian news agencies quoted Krasnov as saying.
“But we will do everything possible to make sure that it is not left unattended,” Krasnov added.
“For sure it has raised jitters,” said Rene Pischel, head of the Moscow branch of the European Space Agency, one of Russia’s 15-nation partners in the orbiting station. “The reason for that is the same launcher is being used for manned launches and in addition to that, you have this sequence of failures… That of course makes everybody very cautious.”
Keeping Borisenko, Garan and Samokutyayev in orbit will buy more time to resolve the problem. They have already spent nearly 160 days in space. Return dates are dictated by the six-month lifespan of the Soyuz capsules docked at the station, and so that landings occur during daylight in Kazakhstan.
That would leave incoming station commander Mike Fossum, cosmonaut Sergei Volkov and Japanese astronaut Satoshi Furukawa to staff the outpost, a US$100 billion project of 16 nations, until their scheduled return in mid-November.
If a replacement crew is not launched before then, the station will be left untended for the first time since November 2, 2000, when the first live-aboard crew arrived.
The station could survive unmanned, with many experiments including the Alpha Magnetic Spectrometer particle detector continuing to operate.
Human research experiments, however, would end, as would flexibility to handle station maintenance and operations.
“We can command the vehicle from the ground and operate it fine and remain on orbit indefinitely,” NASA space station programme manager Mike Suffredini told reporters during a conference call yesterday.
Following the final US space shuttle flight in July, the station has enough supplies to last until next summer, despite the loss of 3 tons of cargo in the botched launch.
The shuttles’ retirement is not a factor in the current situation with the station, Suffredini said.
Soyuz capsules are always needed at the outpost to serve as lifeboats, and none will be launched until the cause of the Progress launch failure is found and fixed.
With the retirement of the space shuttle, the United States turned over all crew transportation to Russia, at a cost of more than US$50 million per person.
Meanwhile, Boeing, Space Exploration Technologies and Sierra Nevada Corporation are being backed by NASA to develop commercial human orbital space transportation services.
US cargo supply ships operated by Space Exploration Technologies and Orbital Sciences Corporation are scheduled to begin deliveries next year.