Philae Comet Lander Unresponsive After Latest Contact Attempt, But There's Still Hope

The European Space Agency's Philae lander has been living in the shadows of a comet for more than a year with many failed attempts to restore communication by the agency. The most recent attempt to turn Philae's stabilizing momentum wheel Sunday was met with no response, the German Aerospace Center (DLR) revealed on Twitter Monday.

There's still hope that Philae will respond before the window for further communication with the ship ends at the end of January.

"Time is running out, so we want to explore all possibilities," Stephan Ulamec, Philae lander manager at the DLR, said in a statement. The DLR attempted to move Philae's momentum wheel in an attempt to place the lander in a better location for future contact attempts.

The wheel's movement could also remove some of the dust that may be sticking on Philae's solar panels. The DLR and ESA will attempt to contact Philae twice a day until Jan. 21, the German agency said on Twitter. By the end of January, Comet 67p will be more than 300 million kilometers (over 186 million miles) from the sun. At that distance, it will be too cold for Philae to operate.

After a historic summer rendezvous with a comet in 2014, the Rosetta spacecraft spent the next few months in orbit around Comet 67p Churyumov-Gerasimenko preparing for its next feat. In November 2014, everything was set for Rosetta to place the Philae lander on Comet 67p, but Philae was unable to anchor itself to the rock.

While Philae tumbled away from its targeted landing site, the lander achieved 80 percent of its first science mission. The data collected by Philae in that short period revealed that the comet's surface is home to complex molecules along with a temperature that rises and falls throughout the day. Philae woke up briefly in June 2015, with the last signal received by the ESA and DLR on July 15. The Rosetta spacecraft has been healthy and sending data during that time, and its mission was extended to September 2016.

"We want to leave no stone unturned," Cinzia Fantinati, an operations manager on the DLR control room team, said in a statement.