The European Space Agency (ESA) still has a number of unanswered questions regarding the plight of the Philae lander since the probe made a historic landing on Comet 67P/Churyumov-Gerasimenko. ESA scientists, for instance, do not know where the lander has exactly touched down.
When the lander's battery drained not long after its landing, scientists expressed their optimism that the probe would still come alive and transmit valuable scientific data from the surface of Comet 67P. Now, ESA scientists estimate that the lander could possibly wake up again in May.
The ESA is hopeful that the lander could come back to life as Comet 67P gets closer to the sun. The Philae lander needed 6.5 hours of light for each 12.4-hour comet day in its initial landing spot. The current location, however, only provides it with 1.3 hours of light for each comet day, which is insufficient to power it.
Scientists are aware that the Philae has landed in the shade of a rock formation, and this is the reason why it cannot make use of its solar panels needed to recharge its batteries. The nearer the comet gets to the sun, the greater the probability is that the lander can accumulate enough solar power to wake up once again.
"Now we need the extra solar illumination provided by the comet's closer proximity to the Sun by that time in order to bring the lander back to life," said Lander Project Manager Stephan Ulamec from the German Aerospace Center (DLR).
By May, the sun will be inclined in a way that it will be directly overhead of the Philae's known landing zone albeit the probe's orientation won't allow it to make full use of the maximum illumination. Scientists likewise think that if the Philae has survived the low temperatures, the earliest it can get warm enough to boot up will be in late March.
It will be between May and June before there would be sufficient solar illumination for the probe to use its transmitter and once again be able to communicate with Rosetta, its mother spacecraft, which was launched to conduct a detailed study of Comet 67P. The Philae, in particular, requires about 17 watts of power to wake up.
If the Philae manages to come alive once agin, it may be able to take some interesting data as Comet 67P starts behaving in a new manner as it approaches the sun.
