European Space Agency officials are pointing toward the moments as the Philae lander get closer to the sun as being the important, and defining moments for this particular craft in getting it revitalized. As the Comet 67P gets closer to the sun, scientists have confirmed that it is entirely possible that the lander will jump back into action, after it’s batteries are given time to recharge from the solar panels on the lander.
The lander rests right now in the shadow of a large cliff that is ultimately shading the lander from gaining any light, which the craft desperately needs to recharge its batteries. Fortunately, the craft was able to execute all of the investigatory and experimental missions that it planned on executing before those batteries ran out. However, the last thing scientists were able to do before the craft lost all power was move the lander slightly, by rotating it, to a position that would be more favorable to exposing the lander to a little more sunlight, and possibly could allow the craft to charge up quicker.
The process though is not as simple as powering the batteries and taking off. Rather the lander has to go through a multistep process to lift off again, and even have a chance of getting back to the Rosetta spacecraft. The process involves the batteries warming back up, being recharged, the lander sending a message to the mother ship, and then be able to move. Ironically though, the amount of energy that would be needed to make that connection is really small. Scientists have openly estimated that the amount of energy needed to reboot the lander and begin the process would only be about as much as the energy that is found inside a handful of AA-sized batteries that would be used in a household.
Ultimately though, the ESA points out that much is uncertain with Philae, and that ultimately this will come down to the position of the craft, come springtime. That will be when scientists will know for certain whether the craft will be able to make the move back to the Rosetta craft.
The idea right now is that future missions will involve taking a greater sampling from a comet. Now that scientists have landed on a comet, they would like to take the next step which would be getting a sample from more locations on the comet. However, that still remains a bit of time out – since it will likely involve a different lander. Due to cost though, and the pending comet-landing proposals that exist right now, we’re likely years out from this becoming a reality again.