On the face of it, it looks like an expensive mishap to rank alongside disappointing Mars landers and malfunctioning telescopes, but the Rosetta mission to the distant 67P comet was being celebrated last night as a giant leap forward in space exploration.
On Wednesday, the washing machine-sized Philae robotic probe made a historic landing on the speeding, icy space-rock 500 million kilometres from Earth. But by yesterday morning the last of its battery power had drained, after a difficult landing left it in a dark spot. Before the batteries failed, though, it had transmitted all the data it had gathered, first to its orbiting mothership and on to mission control in Darmstadt, Germany. In doing so, it may unlock the mysteries of comets, which are made from a material older than our solar system.
In pictures: European Space Agency's Rosetta mission
In pictures: European Space Agency's Rosetta mission
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Image of Comet 67P/CG taken by the Philae lander from a distance of approximately 3km from the surface
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Rosetta's lander Philae took this parting shot of its mothership shortly after separation
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Parting shot of the Philae lander after separation, captured by one of Rosetta's cameras
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A technician celebrates after the successful landing of the Philae lander, in the control room at the ESA headquarters in Darmstadt
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Scientists celebrate at a mission observation centre in Toulouse, southern France as they receive information that Philae has landed on the Churyumov-Gerasimenko comet
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Astronomer Klim Ivanovych Churyumov, who discovered the comet 67P/ Churyumov-Gerasimenko in 1969, reacts after the successful landing of the Philae lander on the comet
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A model demonstrates how the landing device Philae, of the space probe Rosetta, stands on the comet 67P/Churyumov-Gerasimenko at the press center of the satellite control center of the European Space Agency in Darmstadt, Germany
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An artist impression of Rosetta's lander Philae on the surface of comet
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Picture taken on October 28 by the navigation camera on Rosetta shows the boulder-strewn neck region of comet 67/P Churyumov-Gerasimenko. It was captured from a distance of 9.7 km from the center of the comet
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Picture taken on October 24 shows a raised plateau on the larger lobe of the comet
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The probe is supposed to fly to a comet and put down a small laboratory on the top of it
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A scientist from the European Space Agency with an airworthy copy of space probe 'Rosetta' in the control center in Darmstadt, Germany
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Maneuvers designed for the actual space probe are simulated with the replica. 'Rosetta' will be woken up from an energy saving hibernation after 957 days
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A European Space Agency employee sits in the control room for the Rosetta mission in Darmstadt, Germany
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Scientists at the European Space Agency are expecting their comet-chasing probe Rosetta to wake from almost three years of hibernation
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Europe's Rosetta probe on a NASA mission
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NASA is participating in the European Space Agency's Rosetta mission, whose goal is to observe one such space-bound icy dirt ball from up close for months on end
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An impression of the Philae lander
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ESA probe Rosetta with Mars in the background. The three-tonne probe blasted off aboard an an Ariane V rocket from Kourou, French Guiana in 2004
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Rosetta orbiter deploying the Philae lander to comet 67P/Churyumov–Gerasimenko, the spacecraft measures 32 m across including the solar arrays, while the comet nucleus is thought to be about 4 km wide
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The spacecraft, festooned with 25 instruments between its lander and orbiter (including three from NASA), is programmed to 'wake up' from hibernation
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An Ariane V carrying the three-tonne probe Rosetta blasting off from Kourou, beginning a decade-long quest to hunt a comet in the depths of the Solar System and shadow it around the Sun in a bid to tease out secrets of how life began on Earth
It was a "rollercoaster" week for mission manager Fred Jansen, but with his team at the European Space Agency (ESA) he can now start analysing a treasure trove of information.On landing last week, the probe's harpoons failed to fire and it bounced twice before coming to rest more than half a mile from its original landing site in a spot where ESA engineers feared it would not be able to recharge its solar batteries.
Despite this, it was yesterday confirmed that the lander successfully returned data from all 10 of its instruments. The machine "performed magnificently under tough conditions", said lander manager Dr Stephan Ulamec. "We can be fully proud of the incredible scientific success Philae has delivered."
What is not known is whether, having rotated its solar panels to receive maximum illumination, the lander will be able to reboot as the comet approaches the Sun. Engineers had been able to push the probe up by about four centimetres, before performing a 35-degree twist.
"The official position is that we don't expect to hear from Philae again," said Christopher Carr, a principal investigator for the Rosetta orbiter. "All the science instruments have done what they needed to do; so essentially it's been a complete success.
"In many respects now the lander mission is done – the orbiter mission is starting," said Mr Carr, a senior research lecturer at Imperial College London. "We may hear from Philae again, we may not, but even if we can't, there's a whole Rosetta mission as we follow the comet closer to the sun and observe it turning into hopefully a really beautiful comet."
Mr Carr said it could be anything from weeks to more than a year before illumination from the Sun is strong enough to potentially recharge the Philae lander. This, he said, would result in limited power and, by this point, the comet's surface will be increasing hostile. "It might get knocked over, theoretically it could even get blown off."
For the orbiter team, the "most exciting" stage of the mission, in the months before August 2015, is approaching. During this time the comet will start boiling off gas. "It's all about observing the evolution of the activity once it becomes like a classical comet," said Mr Carr.Reuse content