Battery Depleted, Rosetta’s Philae Lander Shuts Down, Possibly For Good

Chuck Bednar for – Your Universe Online
As had been feared, the Rosetta mission’s Philae probe has run out of power following a rough landing that caused it to come to rest in the shade, thus preventing its solar panels from receiving enough sunlight to keep its battery charged, ESA confirmed on Saturday.
As we reported Friday, Philae bounced twice during its Wednesday descent before finally settling down in an area of Comet 67P/Churyumov-Gerasimenko (67P/C-G) approximately one kilometer (0.6 miles) from its intended destination. The lack of sunlight in this area meant that Philae would be receiving just 1.5 hours of sunlight per day instead of the anticipated six to seven.
In a Saturday blog post, the ESA confirmed that the lander’s batteries had become depleted, and that without enough available sunlight to recharge them, it had fallen into “idle mode” for what could be “a potentially long silence.” In this mode, all of its instruments and most of its on board systems have been shut down, the agency explained.
“Prior to falling silent, the lander was able to transmit all science data gathered during the First Science Sequence,” DLR’s Stephan Ulamec, Lander Manager, said in a statement issued from the Main Control Room of the European Space Operations Centre (ESOC) on Saturday. “This machine performed magnificently under tough conditions, and we can be fully proud of the incredible scientific success Philae has delivered.”
Before it was forced to cease operations early Saturday morning, Philae “transmitted data and black-and-white photos back to Earth and ESA scientists. The pictures appear to indicate it landed in some sort of shadow, possibly the shadow of a cliff,” CNN’s Ben Brumfield and Chelsea Carter noted. “Philae turned on its instruments, drilling for samples, and while there was still time, transferred data.”
Future contact with the probe will not be possible unless Philae receives enough sunlight for its solar panels to reactivate the lander. To improve the chances of that happening, ESA sent commands to the probe that caused its main body – which contains the solar panels – to rotate, potentially exposing them to more sunlight. However, the agency noted it is unlikely that it will be able to re-establish contact with Philae in the days ahead.
Despite the lander’s uncertain future, ESA’s ambitious 10 year, 310 million mile Rosetta mission will continue. The orbiter itself is scheduled to spend the next several months analyzing Comet 67P/C-G, and will maintain its orbit through the end of 2015. During that time, Rosetta will use a suite of 16 instruments to perform ongoing analysis of the comet as it approaches the sun, and then move further out into deep space.
In a statement issued after Philae landed on the comet Wednesday, ESA Director General Jean-Jacques Dordain said the Rosetta mission had “secured a place in the history books: not only is it the first to rendezvous with and orbit a comet, but it is now also the first to deliver a lander to a comet’s surface.” Dordain added that the endeavor would help open “a door to the origin of planet Earth and fostering a better understanding of our future.”
FOR THE KINDLE – The History of Space Exploration: redOrbit Press
Follow redOrbit on Twitter, Facebook and Pinterest.