The Rosetta spacecraft and Philae lander have likely sent their last communication signal to mission managers on Earth.
According to The Verge, the European Space Agency has heard nothing from Comet 67P/Churyumov-Gerasimenko since sending out a blind command Monday. By the end of January, the comet will probably be too far from the sun for Philae to recharge its battery.
When Rosetta dropped Philae for a soft landing on the comet in Nov. 2014, the lander bounced several times and wound up where the sun's rays could not recharge it. But as the comet drew closer to the sun, the ESA was able to get in touch with Philae, though it has emitted nothing since July.
"Time is running out, so we want to explore all possibilities," Stephan Ulamec, Philae's project manager at the ESA, said in a statement Monday. "Unfortunately, Philae's silence does not bode well."
@isapinza The commands for @Philae2014 were executed as planned, but no signal was received. (KR)
— DLR - English (@DLR_en) January 11, 2016
Mission managers tried to command Rosetta to reposition Philae by switching on its momentum wheel.
"We did not get a signal, so we do not know whether either the command has not been received, or if there is not enough power at the lander, or whether the communications unit is damaged," Ulamec told Gizmodo. "So we did [a few commands] yesterday and will continue to do a few more commands."
Mission managers, Ulamec in particular, were pessimistic about the possibility Rosetta would succeed. Regardless, the ESA accomplished something that had never been done by executing a soft landing on a comet.
