Scientists expressed confidence today that the Philae lander will wake up once the comet it is riding gets closer to the sun in early 2015.

The question, said Jean-Pierre Bibring of the Institut d'astrophysique spatiale in France, is whether its delicate insides will still be in working order after months in the deep freeze of space.

The probe bounced upon landing last month on the comet known as 67P/Churyumov-Gerasimenko, and came to rest in the shadow of a cliff, depriving it of much of the solar power it needs to operate. Philae went to sleep a few days later when its main battery went dead.

But nothing was broken during the "acrobatic" landing, said Bibring, one of four scientists connected to the European Space Agency project who provided an update during a news conference Wednesday in San Francisco.

"All the systems worked perfectly," Bibring said. "The deployment worked. Everything worked. So really the question is whether or not some electronics might suffer from the cold. But we think most … already went through very low temperatures."

The probe's camera can operate at –150 C, for instance, he said.

"I think we made a very robust system."

The probe is expected to wake up in February or March as the comet approaches perihelion — the portion of its elliptical orbit when it is closest to the sun.

In the meantime, there is a chance Philae could collect a few watts of power as the sun rises and sets over the horizon of the small comet. The probe needs about 15 watts to operate.

Scientists still don't know exactly where Philae landed. Its mother ship, Rosetta, continues to orbit the comet — collecting scientific data and searching for the errant lander.