The European Space Agency says it has abandoned efforts to contact Fobos-Grunt, increasing the likelihood that the errant probe will plunge toward Earth.
The unmanned probe was to head to the Martian moon Phobos on a 2 1/2-year mission to take soil samples and fly them back to Earth. But the probe became stuck in Earth orbit after its Nov. 9 launch and attempts to send commands that could propel it toward the Mars moon have been unsuccessful.
The ESA said in a statement Friday that although the agency has halted efforts to contact the probe, it will resume if any changes are reported by the Russian space agency.
A spokesman for the Paris-based ESA said Russia was going to continue to try to contract the probe over the weekend. Russian space officials could not be reached for comment late Friday.
Russian deputy space chief Vitaly Davydov said last month that if the spacecraft is not sent to Mars, it could fall to Earth sometime between late December and late February.
The failed spacecraft is 13.2 tons, about 11 tons of which is highly toxic fuel. Experts say that if the fuel has frozen, some could survive the plummet to Earth, but that if it is liquid it will likely combust from the heat of re-entering the atmosphere.
The mission was planned to reach Mars orbit next September and land on Phobos in February 2013.