BERLIN — The European Space Agency received no signals from the Philae lander Saturday morning during a scheduled effort to establish communication, the mission chief said.

Paolo Ferri, ESA’s head of mission operations, told The Associated Press, that the Rosetta orbiter did not get any signals from the lander on comet 67P/Churyumov-Gerasimenko.

ESA on Friday ordered a rotating operation to pull the lander out of a shadow so that solar panels could recharge the depleted batteries.

Even if that operation was successful, it may take days or weeks until the batteries of Philae are strong enough to send signals again.

“We don’t know if the charge will ever be high enough to operate the lander again,” Ferri told the AP ahead of the 5 a.m. listening time.

“It is highly unlikely that we will establish any kind of communication any time soon, but nevertheless the orbiter will continue to listen for possible signals.”

On Wednesday, Philae landed next to a cliff that largely blocked sunlight from reaching its solar panels.