After seven months of silence, a robot riding a comet hurtling through space has woken up and phoned home.
The European Space Agency announced Sunday that Rosetta's lander Philae, which landed on Comet 67P/Churyumov-Gerasimenko last November, is operating and sending data back to Earth.
"Philae is doing very well: It has an operating temperature of -35ºC and has 24 watts available," said Philae Project Manager Stephan Ulamec, in a statement. "The lander is ready for operations."
The space agency said the robot communicated with Earth for 85 seconds. Its scientists already have analyzed more than 300 data packets it sent back.
Philae shut down Nov. 15 after working on the comet for about 60 hours. As expected, the lander's battery had run out.
There was concern that Philae landed on the comet in a more shaded area than scientists had planned. That meant it might not have been positioned correctly to absorb enough solar power to turn itself back on.
The European Space Agency has been listening for signs that the lander was till functioning since March 12.
The agency said the lander may have powered itself back on before this recent communication. However, the agency scientists think Philae was unable to communicate in any previous power ups.
Now scientists are waiting for another communication from the lander, which has 8,000 more data packets stored and waiting to be transmitted.
Philae traveled to the comet along with its spacecraft counterpart, Rosetta, on a trip that lasted more than 10 years.
Once Rosetta launched the lander, Philae bounced around on the comet's surface before settling into a spot that was not exactly where scientists hoped it would be. Despite being in the shade, the lander worked continuously for 54 hours after its landing, using all of its 10 scientific instruments to study the comet and return images and data back to Earth.
After that, Philae's battery, as expected, ran out of juice and the robot went quiet.
Scientists from the European Space Agency, as well as from NASA in the U.S., hope that by studying comets, they will get clues as to the origins of the universe. Since ancient comets are thought to be building blocks of the solar system, they also might shed light on how planets and stars were formed, as well as why Earth has water.