BERLIN (AP) — The good news: The spacecraft that landed on a comet has begun drilling beneath the surface to see what secrets the celestial body can reveal. 
 
 This five-image montage of Rosetta's OSIRIS narrow-angle images , released by the European Space Agency ESA on Thursday Nov. 13, 2014 , is being used to try to identify the final touchdown point of... (Associated Press) 
 
 The combination photo of different images taken with the CIVA camera system released by the European Space Agency ESA on Thursday Nov. 13, 2014 shows Rosetta’s lander Philae as it is safely on the... (Associated Press) 
 
 This image released by the European Space Agency ESA Thursday Nov. 13, 2014 was taken by Philae's down-looking descent ROLIS imager when it was about 40 meters (131 feet) above the surface of Comet 67P/Churyumov-Gerasimenko... (Associated Press) 
 
 The bad news: Scientists at the European Space Agency still don't know exactly where the lander is on the comet and are anxiously hoping its batteries hold out long enough for them to get the mining data and adjust the spacecraft's position. 
 
 It was a race against time Friday for the Philae lander, which on Wednesday became the first spacecraft to touch down on a comet. Since then it has sent astonishing images from the icy, dusty comet, 67P/Churyumov-Gerasimenko, and generated some data from instruments such as one that measures temperatures. 
 
 All this is taking place 311 million miles (500 million kilometers) from Earth on a comet hurtling 41,000 mph (66,000 kph) through space. 
 
 Material beneath the surface of the comet has remained almost unchanged for 4.5 billion years, making those mining samples a cosmic time capsule that scientists are eager to study. 
 
 Mission controllers said Philae was able to bore 25 centimeters (10 inches) into the comet to start collecting the samples, but it's unclear whether it has enough power to deliver any information on them. 
 
 The lander has an estimated 64 hours of battery power but has to rely on solar panels to generate electricity after that. Scientists were relieved to learn the batteries still had some juice when the lander resumed contact. Communication was re-established, the ESA said in a tweet late Friday night. 
 
 "Lander now performing a 'lift & turn' of the main body on the landing gear - will last about 10 mins. Telecomm link is good," the agency said in a second tweet. 
 
 Philae bounced twice on the comet before coming to rest Wednesday after two harpoons that should have anchored it to the surface failed to deploy. Controllers still haven't been able to pinpoint its position, but photos indicate it's next to a cliff that is largely blocking sunlight from reaching two of its three solar panels. 
 
 "Maybe the battery will be empty before we contact again," said Stephan Ulamec, head of operations for Philae. 
 
 If the batteries are still running and scientists can extract the scientific data from the craft, they will rotate the lander slightly so that it might capture more sunlight. 
 
 "That would increase the chance that, at a later stage, the lander could wake up again and start talking to us again," Ulamec said. 
 
 After the batteries run out, Philae will remain on the comet in a hibernation mode for the coming months. The comet is on a 6 1/2-year elliptical orbit around the sun. Philae could wake up again if the comet passes the sun in such a way that its solar panels catch more light. 
 
 Meanwhile, the Rosetta — Philae's mother ship, which is streaking through space in tandem with the comet — will use its 11 instruments to analyze the comet over the coming months. 
 
 Scientists hope the $1.6 billion (1.3 billion-euro) project that was launched a decade ago will help them answer questions about the origins of the universe and life on Earth. 
 
 Communication with the lander is slow, with signals taking more than 28 minutes to travel between Earth and Rosetta. 
 
 No matter how long Philae keeps talking to them, scientists say they already have gathered huge amounts of data and are calling the expedition a roaring success. 
 
 "Let's stop looking at things that we could have done if everything had worked properly," said flight director Andrea Accomazzo. "Let us look at things that we have done, what we have achieved and what we have on the ground. This is unique and will be unique forever." 
 
 As for pinpointing Philae's position, Holger Sierks, the principal investigator for the Rosetta's camera systems, said the cameras should have captured the lander's rebound, yielding valuable information on where it came to rest. 
 
 That data has not yet come in, however. Specialists still need to comb one and two square kilometers (0.4 and 0.8 square miles) on the comet to find Philae. 
 
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 Online: www.esa.int/rosetta 
 
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 David Rising contributed to this story. ||||| Lander rotates into slightly sunnier position but apparently too late to charge batteries and keep systems running 
 
 Rosetta mission: Philae goes to sleep on comet as batteries run out 
 
 The Philae lander sitting on Comet 67P/Churyumov–Gerasimenko has run out of power after a successful last-ditch attempt to nudge it into better sunlight apparently came too late to charge its batteries and keep systems up and running. 
 
 
 
 Mission controllers for the Rosetta mission had said on Friday that they were preparing to “hop” the robotic probe in a hope it would settle in a sunnier spot on the comet’s surface. 
 
 Later came a promising announcement. “My rotation was successful (35 degrees). Looks like a whole new comet from this angle,” read a message posted on the lander’s official Twitter account. Earlier the scientists tweeted: “First comet drilling is a fact!” 
 
 But afterwards the Philae mission tweeted: 
 
 Philae Lander (@Philae2014) .@ESA_Rosetta I'm feeling a bit tired, did you get all my data? I might take a nap… #CometLanding 
 
 Philae had apparently been successful in shifting position to gives its shaded solar panels a better chance of catching sunlight. But the moment of success was followed by an announcement that it would have to use up its last battery power in sending a final burst of data back to Earth. 
 
 
 
 If the batteries are not charged the lander goes into hibernation. Without sufficient sunlight on the solar panels the mission shuts down. 
 
 The lander’s legs have a built-in spring action. Commands were uploaded on Friday night to fire them, scientists said, warning there was no guarantee of success. Another strategy under discussion was to spin up an internal flywheel that could make Philae cartwheel out of its predicament but also risked soaking up the last of its battery power. 
 
 Early on Saturday came an announcement that Philae was on the move: 
 
 
 
 Philae Lander (@Philae2014) I just started lifting myself up a little and will now rotate to try and optimize the solar power! 
 
 Since its triple touchdown on Wednesday the spacecraft had been resting on its side, lodged in the shadows of a cliff or large boulder. On Thursday the lander sent back historic first images taken from the surface of a comet. These showed that after its bumpy landing one of its legs was sticking up into space rather than in contact with the surface, raising doubts about whether there was enough spring in Philae’s step to achieve the hop. 
 
 The landing had left Philae surrounded by rocks with only a sliver of light reaching one of its smaller solar panels. Philae was receiving just 1.5 hours of sunlight instead of the expected 6-7 hours. “We are unlucky, in a corner, surrounded by rocks,” said Valentina Lommatsch from DLR’s lander team. 
 
 Despite the akward orientation, the lander’s science package deployed a 1.2 metre arm and a drill. 
 
 Philae Lander (@Philae2014) I confirm that my @RosettaSD2 went all the way DOWN and UP again!! First comet drilling is a fact! :) pic.twitter.com/eE3xL8CGk0 
 
 Philae’s primary mission was always designed to last around 60 hours on its initial battery charge. But engineers covered the spacecraft in solar panels in the hope that sunlight could charge a set of secondary batteries and extend the mission for months. 
 
 Despite the awkward landing, by Friday Stephan Ulamec, Philae lander manager, estimated that 80% of the science Esa was hoping for had been achieved. If the drilling operation succeeded in delivering samples to onboard instruments it would rise to 90%, he said. 
 
 The COSAC (Cometary Sampling and Composition experiment) instrument was chosen to study the first samples rather than the UK-built PTOLEMY instrument. COSAC detects and identifies complex organic molecules from their elemental and molecular composition. 
 
 Ulamec said the choice was made because COSAC uses less power than PTOLEMY, and provided data that could be more easily compared to that taken from the Rosetta orbiter. 
 
 PTOLEMY still generated data by working in “sniffing” mode. Essentially the instrument detected and analysed molecules of gas that naturally drift off the surface of the comet. 
 
 “We juggled everything so that every instrument got to do a measurement, so we are very happy with the mission so far,” says Lommatsch. 
 
 Despite the lander shutting down for now, all might not be lost forever. 
 
 The comet is currently out beyond the orbit of Mars, heading for its closest approach to the sun in August 2015. This will bring it as close to the sun as Earth’s orbit. There the sunlight will be brighter and may just allow Philae to reboot and power up. To that end, the Philae mission tweeted: 
 
 Philae Lander (@Philae2014) My #lifeonacomet has just begun @ESA_Rosetta. I'll tell you more about my new home, comet #67P soon… zzzzz #CometLanding 
 
 “Cross your fingers, or press your thumbs if you are a German, that we hear something from the lander again,” said Lommatsch. ||||| View Images As Philae closes in for a landing, the shadow-pocked surface of the comet 67P is revealed. 
 
 Photograph by ESA/Rosetta/Philae 
 
 A misfire of harpoons, an ancient technology, may have spelled the end of one of the most advanced: Philae, the first spacecraft to send images from the surface of a comet. Unanchored to its comet, the spacecraft drifted into darkness, sending back scientific data even as its solar-powered batteries faded. 
 
 The lander successfully delivered data on the composition of the comet, before losing contact early Friday with the European Space Agency at the Rosetta Mission Operations Centre in Darmstadt, Germany. 
 
 "With its batteries depleted and not enough sunlight available to recharge, Philae has fallen into 'idle mode' for a potentially long silence," an ESA statement announced. 
 
 "It was a very successful mission; it has returned a lot of great data already," said space scientist Alan Stern of the Southwest Research Institute in Boulder, Colorado, a member of the Rosetta science team. 
 
 When Rosetta was originally designed more than a decade ago, the comet lander Philae was conceived of as a 24-hour mission, he says. "People are focusing on the wrong thing to ignore the success of carrying a lander to a comet and getting it on the surface." 
 
 The lander detached from the Rosetta spacecraft orbiting 13.7 miles (22 kilometers) above comet 67P Churyumov–Gerasimenko on Wednesday, landing on the 3.1-mile-long (5-kilometer-long) comet that same day. 
 
 During the landing at its intended site, called Agilkia, the lander's stabilizing rocket and two anchoring harpoons failed to fire. 
 
 On Earth, Philae weighs 187 pounds (85 kilograms), but gravity is so weak on Comet 67P—hundreds of thousands of times weaker than Earth—that it weighs about an ounce there. The harpoons were intended to keep the probe from drifting off the surface of the comet. 
 
 Instead, the unsecured lander bounced off the comet's surface, touching down again nearly two hours later, and then bouncing once more before finally settling, apparently in a shadowed crater beside a cliff. (See "Space Probe Philae Bounces on a Comet.") 
 
 Japan's Hayabusa spacecraft, which landed on an asteroid in 2005, encountered similar travails. Its MINERVA mini-lander was designed to hop on the space rock but instead drifted into space. 
 
 In the shadows, the solar panels of Philae failed to recharge, leaving it helpless after its 2.5-day batteries died. "From now on, no contact would be possible unless sufficient sunlight falls on the solar panels to generate enough power to wake it up," said mission controllers. 
 
 There is some hope of rousing Philae from its sleep. Before the lander shut down, mission controllers rotated Philae's main body about 125 degrees (some 35 percent of the way around its axis), which should have shifted its main solar panel. "This may have exposed more panel area to sunlight," said the ESA, perhaps allowing the lander's batteries to recharge. 
 
 Even if Philae is never revived, the mission will continue to deliver more new science. Scientists are analyzing data from Philae's final communication, and will receive much more information from the Rosetta orbiter, expected to keep orbiting the comet until December 2015. 
 
 The orbiter, currently about 14 miles (22.5 kilometers) away from 67P, will slowly spiral in until it's only a mile or two from the comet's surface, at which point its cameras will be able to pick out details just a few inches across. 
 
 Light reflected from the surface and into spectrographs will tell scientists the contents of 67P's outer crust. 
 
 Rosetta will also add to Philae's data on the composition of gases released from the interior. Already, the orbiter has detected hydrogen sulfide, ammonia, formaldehyde, and hydrogen cyanide along with water and carbon dioxide. 
 
 As the comet makes its closest approach to the sun next summer, the orbiter will study the comet as it heats up. 
 
 Michael D. Lemonick contributed to this article.
– The spacecraft that landed on a comet yesterday is still talking to scientists, but its battery is expected to conk out soon. In what could be a last-ditch effort to save the mission, scientists with the European Space Agency say they'll try to make the Philae lander essentially hop to a different spot—one in which it might get more juice in the form of sunlight for its solar panels, reports the Guardian. Researchers still don't know exactly where the lander is, only that it's surrounded by rocks blocking most sunlight, perhaps next to a cliff, reports the BBC. In the meantime, the lander has begun drilling about 10 inches deep into the comet to collect samples that scientists would love to analyze, given that they are presumably billions of years old, reports the AP. The question is whether the battery will hold out long enough to transmit any data, while the very act of drilling is draining it further. "Maybe the battery will be empty before we contact again," says Stephan Ulamec, head of the lander mission. The battery isn't expected to last beyond tomorrow, but if ESA is able to shift the lander to a sunnier locale, the data collection could go on for months. (The landing hit a few glitches, including anchoring harpoons that didn't fire.)