Grazing crater rim may have saved comet lander

Guest post by Andrew Grant

SAN FRANCISCO — Bumping off the rim of a crater probably saved the robotic comet lander Philae from a cold, dark death, according to data presented December 18 at the fall meeting of the American Geophysical Union. The lucky break has researchers hopeful that the hibernating lander will eventually receive enough solar power to reawaken.

On November 12, Philae descended from the Rosetta spacecraft to comet 67P/Churyumov-Gerasimenko and bounced multiple times off the surface before coming to rest. The landing site is not ideal, but it could have been worse. A new analysis suggests that after catapulting off the surface the first time, Philae grazed the rim of a crater. If not for that collision, Philae would have drifted into a region of total darkness, says lander manager Stephan Ulamec.

As it is, only three of Philae’s six sets of solar panels receive sunlight, and none get more than an hour and 20 minutes per 12.4-hour comet day, Ulamec says. Still, he is hopeful that Philae will be up and running by the summer, when 67P is closest to the sun. By then the intensity of sunlight, and perhaps the amount of daylight at Philae’s location, will be significantly higher than it is now.

Researchers are currently scouring Rosetta images taken December 12-14 in search of the lander’s location.