The Philae lander has gone quiet again, halting its study of Comet 67P / Churyumov–Gerasimenko once more.
Following its bumpy landing on the comet back in November 2014, the lander found itself plunged into darkness at an unlucky resting point, causing it to lose power and lose with Earth. The European Space Agency's craft came back online about a month ago, but now has seemingly lost the sun again.
The blessing and the curse of the probe is that it's solar-powered, meaning it has an unlimited supply of power—so long as it's in the sun. But the Rosetta craft dropped Philae into a dark crater on the surface of the comet, meaning that the probe comes back to life only to go quiet all over again when it is out of view of the sun. There's some indication that an outgassing from the comet may have moved the lander away from where the sun is currently striking the comet and back into indefinite slumber. But the problem may also be the result of a damaged transmission antenna.
"The profile of how strongly the sun is falling on which panels has changed from June to July, and this does not seem to be explained by the course of the seasons on the comet alone," project manager Stephan Ulamec told the .
Either this is it for the lander, or it will wake up one day when it finds itself in the sunlight and start transmitting data again (though ESA says one of its transmitters is currently non-functioning).