Robot on comet unexpectedly revives after 7 months of losing signal.

The Philae probe has unexpectedly re-established contact with the European Space Agency (ESA) after seven months of losing signal, bringing immense excitement to scientists.

These are the final images of the Philae robot from November 2014. Photo: ESA

Last November, Philae landed on Comet 67P/Churyumov-Gerasimenko and operated for 60 hours, communicating and transmitting information back to the ground. However, it then became stuck in a cliff, unable to gather enough energy, and went into hibernation.

Scientists had tried to locate it but failed. However, on the evening of June 13th, the ESA headquarters in Germany unexpectedly received a signal from Philae, with over 300 data packets transmitted to the center. Scientists called it "a greeting from space."

"Hello ESA Rosetta! I'm awake! How long have I been asleep?" Philae called out to Rosetta, the spacecraft that had dropped her onto the comet. "Oh, ESA Rosetta, that was quite a long time, it's time for me to get back to work." The Rosetta spacecraft entered orbit around Comet 67P Churyumov-Gerasimenko in August 2014 after a journey of more than 6 billion kilometers over 10 years from Earth.

Months after Philae lost contact, landing systems engineer Laurence O'Rourke said it needed about 6 watts of power to restart, 9 watts to receive information, and 19 watts for two-way communication with other probes. ESA scientists hoped that, if it received enough sunlight, Philae would revive.

"We are overjoyed that Philae survived the long winter," O'Rouker said. Scientists are eagerly awaiting Philae's data transmission. Its memory can hold up to 8,000 data packets, and analyzing that data will tell them what happened on Comet 67P.

Philae's failed landing last November left it stuck in a dark, cold cliff. However, this coincidentally saved it from being burned by the Sun when the comet approaches the Sun this August, O'Rouker said. "I think we'll get some amazing pictures then."

The Philae robot, weighing 100 kg, is virtually weightless on the comet's surface. It landed approximately 500 million kilometers from Earth, seven hours after separating from the Rosetta spacecraft last November. Scientists hope Philae will help study and understand the materials, including carbon and water compounds, that existed during the formation of the solar system 4.6 billion years ago.

According to VnExpress