Russia on Thursday announced its scientists had for the first time made contact with its stranded Mars probe Phobos-Grunt, a day after the European Space Agency said it had received a signal.
"A signal from the probe has been received and some telemetry data. At the moment our specialists are working on this information," the Interfax news agency quoted Russian space agency spokesman Alexei Kuznetsov as saying.
Interfax said the signal was received at a Russian station at the Baikonur cosmodrome in Kazakhstan on Thursday afternoon.
The European Space Agency said its ground station in Perth, Australia made contact with the probe at 2025 GMT on Tuesday, the first sign of life from Phobos-Grunt since it got stuck in Earth orbit after launch on November 9.
Russian officials had cautioned earlier this week that the chances were very small of saving the mission, which would require reprogramming the probe to send it off on its trajectory to Mars before the window for its journey closes.
The probe had the unprecedented mission to land on the Martian moon Phobos and bring a sample of its rock back to Earth, as well as launch a Chinese satellite into Martian orbit.
ESA said in a statement on its website that the Perth tracking station had also managed to receive a second signal from the probe.
"The signals received from Phobos-Grunt were much stronger than those initially received on 22 November, in part due to having better knowledge of the spacecraft's orbital position," said Wolfgang Hell, ESA's manager for Phobos-Grunt.
One of the main concerns after the failed launch is the risk of an uncontrolled descent back to Earth. Officials have said gravity will pull Phobos-Grunt down within months as its orbit slows and becomes lower.
The spokesman for Russia's military space forces, Alexei Zolotukhin, said Thursday that it was expected that fragments of the probe would fall to Earth in January or February although the exact date would depend on external factors.
One expert said that its surprise show of life had generated hope that the probe could be brought down back to Earth safely, rather than any real prospect that it could be moved out of orbit towards Mars.
"If we are not only able to hear Phobos-Grunt but it is also able to hear us then there is a real chance of ensuring it can make a managed descent from orbit and its fragments plunged into the ocean," said Yury Karash of the Russian Academy of Comonautics.
He told Interfax a managed descent would minimise the risk of the probe hitting a populated area on land.
But he said there was hardly any chance that the probe could fulfil its original mission of going to Mars as its window was essentially closed and it did not have sufficient fuel left.
Explore further: Russia delays Mars probe launch until 2012: report