The first ever space probe to land on a comet has woken up and contacted Earth, the European Space Agency has announced.
Philae was dropped on to the surface of Comet 67P by its mothership, Rosetta, in November last year after a ten-year long journey through space.
The probe worked for 60 hours before its solar-powered battery ran flat.
The comet has since moved nearer to the sun and Philae has enough power to work again, according to the BBC's science correspondent Jonathan Amos.
A Twitter account, @Philae2014, which provides updates of the lander's activities posted on Sunday:
"Hello Earth! Can you hear me? #WakeUpPhilae"
"Philae is doing very well: It has an operating temperature of -35ºC and has 24 Watts available," explained project manager Dr. Stephan Ulamec. "The lander is ready for operations."
In a statement posted on its website, the European Space Agency said: "The signals were received at ESA's European Space Operations Centre in Darmstadt at 22:28 CEST on 13 June. More than 300 data packets have been analysed by the teams at the Lander Control Center at the German Aerospace Center (DLR)."
The statement added: "For 85 seconds Philae "spoke" with its team on ground, via Rosetta, in the first contact since going into hibernation in November.
"When analysing the status data it became clear that Philae also must have been awake earlier, we have also received historical data - so far, however, the lander had not been able to contact us earlier."
The ESA said their scientists were awaiting further transmissions from the probe which will tell what happened on the comet within the last few days.