The Philae lander space probe thought lost has woken up some seven months after officials thought it marooned in the shadows on a comet, the European Space Agency said on Sunday.
ESA said it had received signals from the lander late on Thursday, which began "speaking" with its team on the ground for the first time since it went into hibernation following a botched landing on the comet in November.
"Philae is doing very well," said project manager Stephan Ulamec in a statement on ESA's website. "The lander is ready for operations."
Scientists believe that the probe is receiving increasing amounts of sunlight as the comet speeds closer to the sun, enabling its solar panels to produce the power needed for it to send data.
In the shadows, Philae's solar panels, which were meant to power the probe after its batteries ran out several days after landing, received far less than the expected six to seven hours sunshine per day.
Scientists hope that samples drilled from the comet by Philae will unlock details about how the planets – and possibly even life – evolved. The rock and ice that make up comets preserve ancient organic molecules like a time capsule.
The lander was released from its mothership Rosetta in November as it orbited the comet, in the climax of a 10-year mission for the ESA.
But harpoons to anchor it to the surface failed to deploy and it bounced twice before floating to rest two hours later.
Comets date back to the formation of the solar system some 4.6 billion years ago. Scientists suspect comets delivered water to Earth when they collided with the planet aeons ago.
(Reporting by Thomas Atkins; Editing by Alison Williams)