European scientists received data from the newly revived comet lander Philae on Thursday night, a boost to the team as they try to establish a secure line of communication for their historic scientific experiments on the surface of the comet. The European Space Agency landed Philae on comet 67P/Churyumov-Gerasimenko in November, but the lander bounced and landed in a position too shadowy to power its solar panels. As the comet approached the sun, the lander surprised scientists by waking up and sending signals to Earth on June 13. However, since then scientists have struggled to restore a secure data link between Philae and the orbiting Rosetta mothership. The secure link is needed for the scientists to relay commands to Philae's instruments and receive data back from the surface of the comet.
Philae radioed Rosetta for 12 minutes on Thursday evening, and was able to transmit data from one of its instruments, CONSERT, which is probing the internal structure of the comet, the DLR German Aerospace Centre said on Friday. The team, which had not received communication from Philae since June 24, had attempted to turn on the CONSERT instrument on July 5 but were not sure if the command had been picked up.
"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 the DLR in Cologne.
However, the team is still unsure as to why Philae managed to communicate on Thursday but not before, the statement said. "The new information will help us understand why we're having these difficulties communicating with Philae," Geurts said.