The scientists at the European Space Agency (ESA) faced a nervous wait this morning after it emerged that the history-making Philae probe landed not once but three times on a comet more than 300 million miles from Earth.
However, the ESA confirmed that Philae is now stable, even after magnetic field analysis from the craft reported three separate landings at 15:33, 17:26 and 17:33 - suggesting a high initial bounce and a second smaller one.
"We are sitting with the weight of the lander somehow on the comet," said project manager Stephan Ulamec. "We are pretty sure where we landed the first time, and then we made quite a leap. Some people say it is in the order of 1 km high."
The bouncing was caused by a combination of the comet's incredibly weak gravity and a failure of both the lander's thrusters (which were supposed to push it into the surface) and its harpoons (which were meant to secure it).
Although the probe is now stable, the lack of anchors means that scientists are unsure if they'll be able to drill into the surface to collect samples. Doing so could make the craft unstable and possibly move it across the comet's surface once more.
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
The fact that the 100kg (220 pound) probe descended some 4cm (1.5 inches) into the surface of the comet was also a concern, suggesting it had landed on a relatively soft top layer of dust.
However, Philae's other instruments and sensors are still operational, with ESA scientist Dr Matt Taylor confirming that they were receiving a "good" signal from the craft, including usable scientific data.
He said: “Now we are busy analysing what it all means and really trying to find out where the lander actually is on the surface.”
Hopefully the probe will remain in place however and Philae will be able to begin several months of experiments, retrieving data about the pseudo-atmosphere of the comet and analysing the surface composition of the craft.
Despite the uncertainty last night, the fact that Philae performed a successful soft landing at all was hailed as one of the greatest achievements in the history of humanity.
“This is the most difficult landing in space history, like landing a balloon in a city centre on a windy day with your eyes closed,” said Matthew Genge, lecturer in earth and planetary sciences at Imperial College London.
Now that it has been confirmed as stable, the Philae lander will travel with the comet as it continues its journey around the Sun. It should witness the plumes of vapourised gases emitted from the icy surface as the comet feels the rising heat of its orbital summer.
And Dr Genge said that this journey, along with Rosetta’s readings from its orbit around the comet, could help answer fundamental questions about the origins of our planet. “Did comets deliver the building blocks of living things and start life on Earth? We may soon know with the help of Rosetta,” he said.Reuse content