Based on the latest report published by the German Aerospace Centre.
Despite Rosetta’s new trajectory scheme, the orbiter is still able to listen out for its lander Philae, in case it has woken up from hibernation. Thus a new listening window opens on Sunday, 12 April.
“The communication unit on the orbiter will be turned on around the clock,” says Dr Stephan Ulamec, lander manager at DLR. “Most likely, Philae will wake up in May or June, but we don’t want to miss the moment if it should have enough energy and a sufficiently high operating temperature to wake up earlier.”
To wake up and listen for signals from Rosetta, Philae must have at least 5.5 watts and an operating temperature above –45 degrees Celsius. With a bit more energy, around 19 watts, Philae would be able to return the ‘call’.
“As we did already last month, we will send blind commands to the lander that will help it make optimum use of its energy for heating and communication,” says Stephan.
Thus, if Philae is already awake, it may be able to receive and run the commands sent, even if it does not yet have enough power to acknowledge having done so.
The team remains excited about the prospect of Philae waking up and being able to send data back to Earth via Rosetta again.
“This first dataset will tell us more about the health of the lander, its temperature, and the amount of energy it is receiving on its solar panels,” says Stephan.
The team hopes there will eventually be enough solar power available to continue with science observations on the surface.
“The closer the comet gets to the Sun, the greater the chances that Philae wakes up,” adds Stephan.