The European Space Agency and German Aerospace Center (DLR) have officially closed the book on the Rosetta mission.

In Nov. 2014, the Rosetta probe dropped the Philae lander onto a comet dubbed 67P/Churyumov-Gerasimenko, the first time any spacecraft landed on a comet. Rosetta has been tracking Philae's activity as the comet made its way around the sun.

According to The Associated Press, mission managers called time-of-death on the Philae probe, determining conditions on the comet would be far too cold for it to function.

Philae bounced when it landed more than a year ago and wound up blocked from sunlight, thus stopping it from charging. Philae was able to communicate with ground control when the comet approached the sun, but things became strained again afterward.

"The chances for Philae to contact our team at our lander control centre are unfortunately getting close to zero," Stephan Ulamec, Philae project manager at DLR, said in a statement. "We are not sending commands any more and it would be very surprising if we were to receive a signal again."

The ESA and DLR last heard from Philae in July.

"The comet's level of activity is now decreasing, allowing Rosetta to safely and gradually reduce its distance to the comet again," Sylvain Lodiot, ESA's Rosetta spacecraft operations manager, said in the statement. "Eventually we will be able to fly in 'bound orbits' again, approaching to within 10-20 km - and even closer in the final stages of the mission - putting us in a position to fly above Abydos close enough to obtain dedicated high-resolution images to finally locate Philae and understand its attitude and orientation."