The European Space Agency's latest attempts to send commands to the Phobos-Grunt have not been successful as the spacecraft did not raise its orbit and remained on track for its re-entry to Earth's atmostphere.
As of latest estimates, the Russian mission's re-entry is expected in mid-January.
Russian news agencies reported that from November 28 to November 29, ESA's ground station in Perth had five opportunities to contact Phobos-Grunt from 18:21 to 03:47 GMT (22:21 - 07:47 Moscow Time) but all attempts to command Phobos-Grunt to fire its engines for reaching higher orbit were unsuccessful.
Russian mission controllers have asked ESA to repeat sending the commands to the trapped spacecraft. However, tracking data revealed that the Phobos-Grunt course was not changed by an engine burn and remained at 209.8 by 310 km. It could be that the spacecraft did not receive the signal or even if it received the data it was not able to conduct the burn due to technical reasons, sources said.
ESA continues to improve its ground stations to be able to send signals to the Russian spacecraft. It has modified its Maspalomas Ground Station in Spain to have a second communication asset along the orbital path of Phobos Grunt.
The modifications that were implemented on the Perth Tracking Station, such as the upgrades to add a "feedhorn" antenna which enabled the facility in Perth to communicate with Phobos-Grunt have similarly been made on the 15-meter dish at this Station.
Russian controllers are expected to confirm a possible orbit raising maneuver tomorrow as more communication opportunities are coming up for the two ESA Ground Stations.
Launched on Nov. 9, the Russian probe was designed to bring back rock and soil samples from the Martian moon Phobos. A Zenit carrier rocket put the spacecraft into an initial elliptical based orbit, but the probe failed to fire its engines to put it on course for the Red Planet.
Meanwhile, Klaus-Juergen Schulz, ESOC's head of ground station systems earlier said that ESA is acting merely as a communications node to Phobos-Grunt and is not concerned with the nature of the commands sent to the spacecraft nor the telemetry received from it.
Zak, author of "Partners in Space" which chronicles the Russian-American cooperation in space, said that depending on the probe's remaining resources and technical condition, the options would be to send the spacecraft away from Earth for safety reasons and for testing; or send it to potential destinations in the Solar System, such as an asteroid, the Moon or even Mars, for a flyby or some other abbreviated mission.