The pioneering Lander Philae completed its primary mission of exploring the comet's surface and returned plenty of data before depleted batteries forced it to go silent, the European Space Agency said Saturday.
''All of our instruments could be operated, and now it's time to see what we got,'' ESA's blog quoted Lander manager Stephan Ulamec as saying.
Since landing Wednesday on comet 67P/Churyumov-Gerasimenko some 311 million miles away, the craft has performed a series of scientific tests and sent reams of data and photos back to Earth.
Philae's landing site allows the Lander to receive only 1.5 hours of direct sunlight during that 12 hour window when the comet rotates and faces the sun. Unfortunately, this short time span isn't enough to power Philae's batteries.
Comet 67P rotates every 12 hours. This is considered as a full day on the comet. This accident might be a major setback for the mission but ESA scientists said they received essential research data from the probe before it became inactive.
The Rosetta team said Philae is in an idle mode that will keep it silent for some time. This mode shuts down of most of Philae's systems and the entire suite of onboard instruments
ESA's mission control center in Darmstadt, Germany, received the last signals from Philae at 7:36 p.m. EST Friday. Before the signal died, the Lander returned all of its housekeeping data as well as scientific data of its experiments on the surface - which means it completed the measures as planned, the ESA blog said.
During a scheduled listening effort Saturday, ESA received no signals from Philae, mission chief Paolo Ferri said.
''We don't know if the charge will ever be high enough to operate the Lander again,'' Ferri had said ahead of the listening time. ''It is highly unlikely that we will establish any kind of communication any time soon.''
The science teams are now studying their data to see whether they have succeeded in sampling any of this material with Philae's drill.
Scientists are also still trying to find the exact spot where Philae landed Wednesday. ''The search for Philae's final landing site continues, with high-resolution images from the orbiter being closely scrutinized,'' the blog said.
Scientists hope the $1.6 billion project might help confirm that comets brought the building blocks of life to Earth. They already know that comets contain amino acids, a key component of cells.
There's a glimmer of hope that this situation might change for the better. Mark McCaughrean, ESA senior scientific adviser believes that as comet 67P moves closer to the sun, Philae will get more light on its solar panels despite its position under a cliff.
Comet 67P's approach towards the sun drastically changes the timing, intensity and angle of sunlight that will hit the Lander's solar panels. The closest approach could occur on August 13, 2015.
