New radio communications from Philae

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On July 9 Philae successfully transmitted data to Rosetta for the first time in more than two weeks.

Although the connection failed repeatedly after that, it remained completely stable for those 12 minutes. “This sign of life from Philae proves to us that at least one of the lander’s communication units remains operational and receives our commands,” said Koen Geurts, a member of the lander control team at DLR Cologne.

The mood had been mixed over the last few days; Philae had not communicated with the team in the DLR Lander Control Center (LCC) since 24 June 2015. After an initial test command to turn on the power to CONSERT on 5 July 2015, the lander did not respond. Philae’s team began to wonder if the lander had survived on Comet 67P/Churyumov-Gerasimenko.

The intermittent nature of Philae’s attempts at communication are puzzling. Normally, they either would have communications or they would not. For good communications to break off like this repeatedly is puzzling. It is almost as if there is a loose wire causing communications to go on and off, which seems an unlikely explanation for this problem.



  • mpthompson

    I wonder if there enough gas in the tank (so to speak) for Philae to attempt to hop out of the shadow that it found itself in after it’s landing? I assume it wouldn’t take much of a puff of the thrusters for a significant hop in such a low gravity environment. If they could, there is always the possibility Philae could end up in a worse situation, but it could also end up in a position much better suited for charging the batteries and get some real science done.

  • They don’t have a thruster option, but see these two BtB posts for other things they can do to shift the lander, assuming they can regain reliable communications:

    Engineers have until Saturday to reposition Philae before its batteries go dead

    Drill baby drill!

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