An unmanned Russian spacecraft on a mission to one of Mars' moons has failed to take its proper course after launch, the Interfax news agency has quoted the head of the Russian space agency Roskosmos as saying.
Vladimir Popovkin, the chief of the space agency, said on Wednesday that an engine failed to fire on the Phobos-Grunt probe after it had reached Earth orbit.
He said the ignition failures were probably due to a failure of the craft's orientation system.
The craft was on a mission to bring back soil samples from Phobos, one of Mars' moons.
In a forum on the mission's official website, Anton Ledkov, an official with the Russian Space Research Institute, said that there was no telemetry being received from the spacecraft.
However, Popovkin said that scientists were still in contact with it, and had three days to set it back on course before its batteries ran out, Interfax reported.
"The engine did not fire, neither the first nor the second burn occurred. This means that the craft was unable to find its bearings by the stars," the agency quoted him as saying.
The craft was launched at 2:16am local time on Wednesday (20:16 GMT on Tuesday) from the Russian-leased Baikonur cosmodrome in Kazakhstan.
Russia's federal space agency said the craft separated successfully from the booster about 11 minutes later.
It was to take the robotic probe a few hours to conduct a series of preliminary manoeuvres before it could head towards Mars.
The return vehicle was to carry up to 200 grams of soil from Phobos back to Earth in August 2014.
Speaking to Al Jazeera, Morris Jones, a Sydney-based space analyst, said that it was unclear what exactly the problem with the craft was.
"They think there may be a problem with the computers, and instead of just resetting it, they may need to upload some more coordinates or some more instructions. And if that's all it takes to get this probe back on its mission, that would be a good thing," he said.
First attempt since 1996
The $170 million mission was to be Russia's first interplanetary endeavour since the Soviet era. A previous robotic mission to Mars in 1996 ended in failure after the probe crashed into the Pacific following an engine failure.
This latest mission was originally scheduled to take place in October 2009, but was postponed after there were delays getting the probe ready.
The 13.2 tonne spacecraft is the heaviest interplanetary probe ever to be launched. Fuel accounts for most of the weight of the craft, which was manufactured at the Moscow-based NPO Lavochkin.
The same company had designed the craft that failed in 1996, and two of its probes launched to Phobos in 1988 also failed. One was lost a few months after launch due to an operator's mistake, and contact was lost with its twin while it was orbiting Mars.
Viktor Khartov, NPO Lavochkin's chief, described the current mission as essential to maintain the nation's technological expertise in robotic missions to other planets.
"This is practically the last chance for the people who participated in the previous project to share their experience with the next generation, to preserve the continuity," Khartov said before the launch, according to Interfax.
"This is going to be a massive blow to Russia if this fails, because they have not tried to reach Mars since 1996 ... and that last attempt was also a failure. So the Russians have not had a successful mission sent to Mars since the fall of the Soviet Union," Jones, the analyst, said.
"It's almost as if missions to Mars are somehow jinxed: they fail for all sorts of reasons. Rockets fail, spacecraft fail, controllers send the wrong instruction - you can pick almost any cause and its brought down a Mars mission at some point in history."