- .Philae made incredible landing on comet 67P today at 3.30pm GMT
- .Philae separated from the Rosetta spacecraft seven hours earlier
- .First image by Philae showed Rosetta 50 seconds after separation
- .Rosetta's images show Philae falling against pitch black of space
- .But a thruster problem could prevent Philae from landing on 67P
- .The cold gas thruster on top of the lander is not working properly
- .Without it, Philae will have to rely on harpoons to attach to comet
- .Rosetta has chased comet 67P/Churyumov-Gerasimenko for 10 years
- .This will be the first time a spacecraft has ever landed on a comet
Rosetta's probe, Philae, has successfully landed on its comet 67P/Churyumov-Gerasimenko.
After a daring seven-hour descent, the probe made space history by becoming the first ever craft to land on a comet.
In a historic speech, Esa director general Jean-Jacques Dordain said: 'It's a big step for human civilisation.
Ahead of the landing, Rosetta took a number of images of Philae during its daring descent. This view shows the lander's consert antennae deployed. It also shows three lander feet and the Rolis descent camera boom
Data from the probe could help reveal how the solar system was first created 4.5 billion years ago.
The confirmation of the landing was relayed via the Rosetta orbiter to Earth and picked up simultaneously by a ground station in Malargüe, Argentina and Madrid, Spain.
The signal was immediately confirmed at Esa's Space Operations Centre, ESOC, in Darmstadt, and DLR's Lander Control Centre in Cologne, both in Germany.
'ESA and its Rosetta mission partners achieved something extraordinary today,' notes Dordain.
'Our ambitious Rosetta mission has secured another 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 probe to a comet's surface.'
Bye Rosetta! This image released shows the Philae lander's view of the Rosetta spacecraft 50 seconds after it was released at 08.35am GMT. It is blurry because the probe was rotating at the time
A view further away taken by Rosetta's Osiris camera. 'It's me… landing on a comet and feeling good!', Philae tweeted
'After more than 10 years travelling through space, we're now making the best ever scientific analysis of one of the oldest remnants of our solar system,' says Alvaro Giménez, Esa's director of Science and Robotic Exploration.
'Decades of preparation have paved the way for today's success, ensuring that Rosetta continues to be a game-changer in cometary science and space exploration.'
'We are extremely relieved to be safely on the surface of the comet, especially given the extra challenge of the comet's unusual shape and unexpectedly hazardous surface,' says Stephan Ulamec, Philae Lander Manager at the DLR German Aerospace Center.
'In the next hours we'll learn exactly where and how we've landed, and we'll start getting as much science as we can from the surface of this fascinating world.'
Engineers were involved in a tense seven-hour wait to find out whether the lander successfully grabbed onto the comet at 3.30pm GMT.
Ahead of the landing, Rosetta was able to capture several other images of Philae during its daring mission using its Osiris camera.
One stunning shot shows the lander's antennae deployed, along with all three lander feet and the Rolis descent camera boom.
Immediately after the image was released Philae tweeted 'It's me…landing on a comet and feeling good!'.
The separation of Philae from Rosetta was confirmed at 9.03am GMT today, and just after 11am GMT mission control in Darmstadt, Germany received a signal confirming the lander was working.
Throughout the day, the lander has been transmitting data and images back to Earth. 'Everything looks really, really good,' said Philae lander manager Stephan Ulamec.
However, the success of the mission hangs in the balance because Philae has a faulty thruster, which means it may have to rely solely on harpoons to attach itself to the surface.
There are a number of things that could go wrong with the mission. For instance, Rosetta might not release Philae at the right spot if the thrusters are activated at the wrong time. Jets of gas spewing from the comet could also cause problems during the descent. Pictured is an overview of potential problems facing Philae
The cold thruster is used to push Philae closer to the comet.
Without it, Philae will have to rely on its three landing screws and two harpoons to successfully attach itself to the surface.
However, if the thruster is reactivated and all goes to plan, at touchdown a landing gear will absorb the force of the landing.
Ice screws in the feet and a harpoon system will lock to the comet's surface and the thruster will push it down into the surface to counteract the impact of the harpoon.
Before Philae's release, Esa said there was 'no going back'.
'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, a senior lecturer in Earth and planetary science at Imperial College London.
At 08.35am GMT the mission control team in Darmstadt, Germany, sent a command to release the Philae probe from Rosetta's grip.
The probe was in free fall for during 'seven hours of terror', before attempting to land on the icy surface of comet 67P/Churyumov-Gerasimenko at a site called Agilkia.
Anxious: Scientists (mission controller Paolo Ferri pictured in foreground) face a gruelling seven-hour wait to discover if the Philae probe has managed to safely land on the comet it has chased for 10 years
Rosetta has chased comet 67P/Churyumov–Gerasimenko through space for more than ten years in what has been described as 'the sexiest, most fantastic mission ever'. After a four billion mile (6.5 billion km) journey, it is now positioned in an orbit 19 miles (30 km) away from 67P
At 08.35 GMT today, mission control in Darmstadt, Germany sent a command to release the Philae probe from Rosetta's grip. This picture shows the boulder-strewn neck region of Comet 67P/Churyumov-Gerasimenko. It was captured around 4.8 miles (7.7km) from the surface of the comet
'We'll need some luck not to land on a boulder or a steep slope,' said Stephan Ulamec, Philae Lander Manager at the DLR German Aerospace Center.
Speaking to Astronomy Now, Head of Mission Operations Paolo Ferri said they had received both positive and negative readings from the thruster.
This means they are unsure if it still might work ahead of the landing attempt. Without it, the landing will be a lot more difficult - but, crucially, it is still possible.
'We knew we need a lot of luck on the surface for this lander to survive,' he said.
'Now with this inconsistent results of the priming of the system we have additional anxiety.
'We don't know whether the motor is working or not. We have inconsistent readings.
'I always like to be optimistic and I hope the 50 per cent that tells us the positive news is the right one but we can't say [for sure]. We will only know it when on the surface.
This picture from mission control shows the team preparing to receive confirmation from the Philae lander that it had separated from Rosetta earlier this morning
This graphic details how the Philae lander will touchdown on the surface of comet 67P. Without its cold thruster on top, however, the landing is due to be even more risky than thought
The Philae lander is now on its way to the comet (illustration shown). Throughout the day images from both Philae and Rosetta should be returned to Earth picturing the various stages of the landing
TO BOLDLY GO WHERE NO SPACECRAFT HAS GONE BEFORE
William Shatner, who played Captain James T. Kirk in the TV series Star Trek, has wished the Rosetta team good luck ahead of the landing attempt in a video recorded by himself.
'Good luck Rosetta, Philae's gonna land,' he says in the video.
'I am so excited and I wish you such good luck.
'Good wishes from all of us here in Los Angeles.'
Shatner posted the video to his Twitter page, to which Esa responded: 'Thank you captain!'
While the 83-year-old is known around the world as Captain Kirk from the fictional show Star Trek, he is also a big proponent of real space exploration.
In the past he has spoken with Nasa and Esa on Twitter, occasionally 'checking in' to see how the agencies are doing.
Back in August he tweeted: 'How is @NASA doing today?'
Nasa responded: '@WilliamShatner Good day, Captain. #ISS is in standard orbit and Commander Swanson has the conn. Hope you're having a great weekend!'
To which Shatner replied: '@NASA Very good news!'
Shatner played Kirk in Star Trek: The Original Series but also reprised his role elsewhere including in seven movies.
Shatner is pictured left in his video wishing the Rosetta team good luck and right in Star Trek: The Original Series back in 1967
The team in Darmstadt, Germany are pictured here celebrating as news of Philae's separation from Rosetta was received earlier this morning
Philae's cold thruster is nitrogen-powered and is designed to fire on landing in order to prevent the probe from flying off into space due to the comet's weak gravity.
In order to prepare cold-gas jets, scientists use one of two pins to puncture a wax seal on the thruster's gas tank.
Experts detect success by the change in pressure in the piping system.
However, this morning mission controllers did not see pressure increases after two attempts with each of the two pins.
But according to the industry provider, there may still be a chance that retrying the puncture of the wax seal would succeed, even after four failed attempts.
Philae must now rely on its two harpoons and ice screws to hold it to the surface. Whether that will be enough - or whether the lander will bounce off before they can secure it to the surface - remains to be seen.
If all goes to plan, Philae should send a signal back to mission control engineers at around 4pm GMT.
Space adventure: The probe will analyse various components of the comet's surface (diagram pictured)
Pictured is one of Rosetta's two massive solar wings, which have kept Esa's comet-chaser powered out in the cold depths of space
This morning it was revealed that the cold thruster - a nitrogen thruster - on top of the Philae lander was not working properly. This means the Philae lander will have to rely on its screws and harpoons (illustration shown) to ensure it does not bounce off the surface of the comet
This is the expected view of Philae taken by Rosetta as it makes its way to the surface of the comet today
Pictured is a separate Esa Rosetta control team in Toulouse, France awaiting news of the separation
Esa has now successfully made contact with the Philae lander after it separated from the Rosetta spacecraft this morning at 08.35am GMT. It is now heading towards the comet and is expected to attempt to land on the surface at 4pm GMT. Pictured right is Paolo Ferri, Head of Mission Operations, celebrating making contact
WHAT IS THE MIDAS INSTRUMENT?
The Midas instrument on Philae is designed to study the dust particles flung from the comet
Midas is the Micro-Imaging Dust Analysis System. It is designed to study the dust particles flung from the comet as it is heated by the sun and becomes active.
When comets pass through the inner solar system, the ices buried below their dark surface are gradually heated. As this gas streams away from the comet's surface, it drags along dust particles – themselves tiny pieces of rock, ice and organic material.
Sunlight reflected from billions of such particles result in the beautiful dust tails seen from Earth on particle population, size, volume and shape.
Midas is one of several instruments that will study cometary dust. To collect particles Midas has a funnel, which usually points towards the comet.
Behind this is a wheel with sticky targets mounted around its circumference. After dust has been collected, the wheel is rotated to move the dust to the microscope for analysis.
By scanning over the dust grain, line by line, scientists can build a 3D picture. Knowing the size, shape and structure of these particles tells us about how and where these particles formed.
These particles are remnants of when the solar system formed 4.5 billion years ago and could reveal how planets formed, and perhaps on life came to be on Earth.
Speaking live on TV, Matt Taylor, project scientist of Rosetta, talked about the complexities of the mission.
'I said she was sexy but I never said she was easy,' he said.
The comet is currently 300 million miles away (480 million km), and is travelling through space at about 34,000 mph (55,000 km/h).
Yesterday flight managers gave their 'OK' to the first of four checks that must be carried out before the probe Philae can descend from its orbiter craft onto a comet in deep space this afternoon.
The checklist was preceded by a brief moment of worry when Philae 'took a bit longer than expected' to be activated, said Paolo Ferri, mission leader at Darmstadt.
'We were a bit worried at first that the temperature would be wrong (for the descent) but it all worked out. We didn't lose any time,' Ferri said.
No one has ever attempted such a daring feat, and even Esa engineers admit they initially thought it sounded more like science fiction.
If they manage it, Rosetta and Philae could help unravel secrets of how the solar system formed 4.5 billion years ago.
Rosetta has also been aiming to work out the plasma characteristics of the comet (illustrated)
At 0835am GMT the team in Darmstadt, Germany (picture from mission control shown) sent a command to release the Philae probe from Rosetta's grip
Esa also revealed this new image showing how the comet would dwarf London
Engineers at Rosetta mission control are anxiously counting down the hours before they attempt to make space history by landing the Philae probe on comet 67P. Pictured is an artist's impression
Rosetta has chased comet 67P/Churyumov–Gerasimenko through space for more than ten years in what has been described as 'the sexiest, most fantastic mission ever'.
After a four billion mile (6.5 billion km) journey, it is now positioned in an orbit 19 miles (30 km) away from 67P.
Emotions at mission control are already running high. 'This, for me, is a wonderful dream come true,' Paolo Ferri, mission director told MailOnline. 'Just thinking about it…I have tears in my eyes.
'You spend a lot of your time in very odd situations with [Rosetta], working weekends, and getting calls in the middle of the night. It's not fair to compare it to a relationship with a human, but it's very close.'
When it was launched in 2004, Rosetta was so far from 67P that it had to pass Earth three times and Mars once, so that it could use the planets' gravity to slingshot its way deep into the solar system.
The spacecraft will spend more than a year studying the comet, which is made up of material left over from when our solar system was first created 4.5 billion years ago.
Ahead of the landing, Esa has published a series 'beauty shots', taken by Rosetta's navigation camera, revealing the varied and dramatic terrain of the mysterious rock.
TOUCHDOWN ON THE COMET: PHILAE'S DETAILED LANDING TIMELINE
Rosetta will release Philae at 08:35 GMT/09:35 CET on 12 November at a distance. Pictured is an artist's impression of the lander on Comet 67P
Rosetta will release Philae at 08:35 GMT/09:35 CET on 12 November at a distance of 14 miles (22.5km) from the centre of the comet.
The landing will be about seven hours later at around 15:30 GMT/16:30 CET.
During the descent, Philae will take images and conduct science experiments, sampling the dust, gas and plasma environment close to the comet.
It will take a 'farewell' image of the Rosetta orbiter shortly after separation, along with a number of images as it approaches the comet surface.
It is expected that the first images from this sequence will be received on Earth several hours after separation.
Once safely on the surface, Philae will take a panorama of its surroundings. Again, this is expected back on Earth several hours later.
The first sequence of surface science experiments will begin about an hourafter touchdown and will last for 64 hours, constrained by the lander's primary battery lifetime.
Longer-term study of the comet by Philae will depend on for how long and how well the batteries are able to recharge, which is related to the amount of dust that settles on its solar panels.
It is expected that by March 2015, as the comet moves closer in its orbit towards the sun, temperatures inside the lander will have reached levels too high to continue operations, and Philae's science mission will come to an end.
But the Rosetta orbiter's mission will continue for much longer. It will accompany the comet as it grows in activity until their closest approach to the sun in August 2015 and then as they head back towards the outer solar system.
Illustrated here are the various scientific instruments on the Philae lander that will be used to study the comet when it is attached to the surface
Rosetta has chased comet 67P/Churyumov–Gerasimenko through space for more than ten years in what has been described as 'the sexiest, most fantastic mission ever' (illustration of solar system shown)
The images shows a raised plateau on the larger lobe of Comet 67P/Churyumov-Gerasimenko. It was captured from a distance of 6 miles (9.8 km) from the center of the comet
Paolo Ferri, head of Esa Operations, is overjoyed after receiving Rosetta's acquisition of signal in January
The mission began as a concept about three decades ago and was the brainchild of Gerhard Schwehm, former Rosetta Project Scientist (pictured in the 1980s)
Incredibly, many of the images were taken at less than six miles (10km) from the comet's surface, and highlight what a challenging task Philae engineers have ahead of them.
The Philae probe aims to analyse the comet in more detail than Rosetta ever could. The results, Esa claims, could completely rewrite the history of how the Earth formed.
As Philae descends, it will be travelling at walking speed of 3ft (one metre) per second relative to 67P while the duck-shaped rock is rotating constantly.
Philae will need to be released with pinpoint accuracy as its landing site contains a mix of sheer cliffs and deep craters – any of which could scupper its chances.
Scientists are aiming to land on a spot named 'Agilkia' on the smaller 'head' lobe of 67P after Philae is released from a distance of 14 miles (22.5km) from the centre of 67P.
Rosetta has been taking scientific readings of the comet since it arrived, including measurements of the magnesium on the surface (shown)
The daring descent Philae (artist's impression shown) will take seven hours from separation. It will be exactly nine years that a similar landing attempt on an asteroid by Japan's Hayabusa failed in 2005
This image shows the Agilkia landing site on Comet 67P/ChuryumovGerasimenko, taken with Rosetta's navigation camera on 6 November. It was captured at a distance of 22 miles (35.5km)
Jose Pellon-Bailon, one of eight flight engineers responsible for Rosetta, told MailOnline there are a number of things that could go wrong during the descent.
For instance, Rosetta might not release Philae at the right spot if the thrusters are activated at the wrong time.
Jets of gas spewing from the comet could also cause problems during, moving Philae off course.
Another concern is the strange duck-shape of the comet, which means Philae could crash land, damaging its instruments.
Emotions in the control room can run high. During launches, a moodily-lit space (pictured) with curved consoles facing the main screens, is staffed by specialists responsible for different parts of Rosetta
And even if Philae lands safely, it will need to attach itself to the comet using harpoons.
Philae is able to withstand temperatures of 150°C (300°F), but it could become too hot to operate as the comet travels towards the sun.
But if it all goes to plan, it could trigger more mission to comets in the future.
'The other scientific instruments are collecting a huge amount of data and I'm sure they'll provide to the scientific community a humongous richness,' Pellon-Bailon said.
At the moment, communication between Rosetta and mission control take 28 minutes and 20 seconds each way – the time it takes for a signal to travel 315 million miles (510 million km) to Earth.
'It's difficult, in the sense that you are commanding something and you are seeing the effects almost one hour later,' says Pellon-Bailon. 'If we land on the comet, it will be very emotional.'
Ferri's biggest fear isn't that Philae will be damaged during the descent, but that it could fail to send a signal back at all.
'This would be a huge disappointment,' he says. 'Of course, the landing mission would be off, but also we wouldn't have learned why.'
Located in the heart of Darmstadt, around 20 minutes from Frankfurt, Esa's mission control centre will be a hive of activity on 12 November as Paolo Ferri and his team attempt to land Philae on comet 67P
The landing has been described by Esa as 'ridiculously difficult'.
'Imagine the comet as Mont Blanc,' says Ferri.
'You fly with an aircraft at 13.6 miles (22km) in altitude - so twice the altitude of a normal airline.
'At a certain point you have to drop a box and hope that it lands on the mountain within a square km.'
Pellon-Bailon says his team are fully prepared, even down to what they will eat on the day.
Peanuts are crucial. 'We found out that people at Nasa eat peanuts on the day of the special activity. In a mission that is problematic, they will always have peanuts on the table.'
Esa has inherited the superstition, and Ferri confirms that it's vital to the success of the mission. 'I'll also be wearing the same tie I wore when Rosetta launched ten years ago,' he says.
The bizarre rituals at mission control are hoped to steady nerves as engineers perform complex manoeuvres around the comet.
Pellon-Bailon says when he first got involved in the mission in the early 1990s, it sounded to him like science fiction. Even now, he can't quite believe they've reached the comet.
Rosetta's target comet, 67P/Churyumov–Gerasimenko, is about 2.48 miles (4km) wide. Here it is shown alongside some of Earth's landmark
'It sounds crazy when you say it out loud,' says Ferri. 'Sometimes I sit back and think, there's a two cubic metre box flying half a billion kilometres away, that is now sending a very faint signal.
'That signal is picked up in Australia, and now I'm looking at it. Then I think, how is it possible?'
But it has been possible, and even if Philae doesn't make it on tomorrow, the mission has already achieved its main objective.
'You have to remember, and we have to remember, this landing is spectacular, but it is only one part of the mission,' says Ferri.
'Whatever happens, data from Rosetta has already rewritten the history of our solar system.'
Mission control in Darmstadt gives the thumbs up after Rosetta's successful separation. Pictured in the right hand corner is Rosetta's official mascot
Rosetta took an incredible selfie of its 131ft (40 metre) solar wings gleaming against the darkness of space. In the background is the comet, Comet 67P/Churyumov-Gerasimenko, with its 'head' and 'body' clearly visible
The reconstructed-colour image, taken early October, indicates how dark the comet appears. On the average, the comet's surface reflects about four per cent of impinging visible light, making it as dark as coal
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