Rosetta is trying to reconnect with Philae – BBC

In hibernation since November, the little robot that landed on the comet 67P could have opened his eyes.

The little Philae robot successfully dropped in November by the European Rosetta probe on the surface of the comet 67P / Churyumov-Gerasimenko, is still missing. But it may be in perfect condition. Its eventful landing had propelled after two rebounds in an acrobatic position on rough terrain. Solar panels, misdirected, not harvested enough light at the time to recharge your batteries. After two days of intensive work, and he swung into “hibernation” mode. Waiting for better days.

Four months later, the comet approached the sun. “There are two times more light energy available today than in November,” says Jean-Pierre Bibring, researcher at the Institute of Space Astrophysics and Philae scientific co-responsible. Not sure that this is enough to get out the little robot from its torpor, but the thing is not impossible.

The local spring comes

“It takes only 5 watts restart the onboard computer but nearly 20 W for communication with Rosetta, says the scientist. It is possible that we have already this power, it depends on the shadows on the panels. We switch gradually from winter to spring local, so the sun rises. It’s a good thing, but as we do not know exactly where Philae, we have no certainty. “Rosetta is indeed too far to distinguish the lander on the surface of the comet. The few close flybys were unsuccessful

The only way to know. Relight the Rosetta communication module off in November to see if Philae beeps. This is what had to be done that night at 2 am. “During the next eight days, there will be 11 windows of two to three hours during which Rosetta will be in a position to exchange data with the lander,” says Sylvain Lodiot in charge of steering the probe to the control center of the European Space Agency in Darmstadt. It takes both Rosetta has alleged landing area in sight and it is lit at this time.

A new attempt in mid-April on failure

If Philae woke up and operational, scientists will be quickly fixed. They can then develop an action plan based on the energy reserves of the robot. If Philae has enough energy to bring his batteries at the temperature of 0 ° C, while their dependents will start. Necessary to bring the power required for most scientific instruments. “One can also walk a few instruments directly to the solar panels,” says Philippe Gaudon, project manager Philae CNES (French Space Agency).

But Philae could also be awake, able to receive instructions but unable to send signals. “This is probably the situation in which we are currently says Philippe Gaudon. This corresponds to ten watts of light energy. In this case, we will try to send commands to the robot focuses on making contact rather than charging its battery. “

If this is not enough, the communication module Rosetta will be off. “We have a new slot during which Rosetta will fly Philae day in mid-April,” says the scientist. This will be the beginning of spring on the comet. The light energy will be three times higher than in November and more vertical sun again. The Adventures of Philae on the comet probably not complete.