The European Space Agency (ESA) on Monday said it now knows where its robotic lander Philae is on the comet 67P/Churyumov-Gerasimenko.
The agency said it had received images showing the lander stuck in a "dark crack." The images were sent back to Earth by a camera on the Rosetta probe after it flew within 2.7 kilometres of the surface of the comet. Until it received the pictures, ESA had been unsure of the precise location of the lander.
Laurence O'Rourke, who coordinated the search for Philae, said in an ESA blog post he was "very excited and thrilled" to have the photo of Philae.
Philae bounced after first touching down on the comet in November 2014, then ended up at a location named Abydos on the comet’s smaller lobe. Having missed its intended landing spot, Philae was left short of sunlight to charge its secondary batteries and after three days went into hibernation.
It woke up and communicated briefly with Rosetta in June and July 2015 as the comet came closer to the Sun and more solar power was available.
The ESA scientists were especially pleased to receive the photos, which were taken on Friday, because there is only a month left in the Rosetta mission.
"This remarkable discovery comes at the end of a long, painstaking search," said Patrick Martin, ESA's Rosetta Mission Manager. "We were beginning to think that Philae would remain lost forever. It is incredible we have captured this at the final hour."
The photos clearly show the main body of the lander along with two of its three legs. The images also provide proof of Philae’s orientation, making it clear why communicating with it was so difficult.
Rosetta is scheduled to descend to the comet's surface on September 30 to investigate the comet from close up, including the open pits, where scientists hope find secrets of the body’s interior structure.