Philae, the first robot to land on a comet, has reached the end of its life and is bidding a final farewell to Earth through a series of sad tweets. “It’s time for me to say goodbye,” Philae tweeted on Tuesday. “Tomorrow, the unit on @ESA_Rosetta for communication with me will be switched off forever…” After launching from a Rosetta probe, Philae landed on 67P/Churyumov-Gerasimenko in November 2014, becoming the first spacecraft to touch down on a comet.