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Engineers at Rosetta mission control are anxiously counting down the hours before they attempt to make space history.

At 08.35 GMT tomorrow, the team in Darmstadt, Germany will send a command to release the Philae probe from Rosetta's grip.

The probe will then be in free fall for seven hours, before landing on the icy surface of comet 67P/Churyumov–Gerasimenko.

Scroll down for video and animation 

At 08.35 GMT tomorrow, mission control in Darmstadt, Germany will send a command to release the Philae probe from Rosetta's grip. This picture shows the boulder-strewn neck region of Comet 67P/ChuryumovñGerasimenko. It was captured around 4.8 miles (7.7km) from the surface of the comet

If all goes to plan, Philae should send a signal back to mission control engineers at around 4pm GMT.

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).

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.

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

On Wednesday, tensions at Rosetta mission control (pictured) in Darmstadt Germany will be running high as space engineers attempt to land Philae onto the craggy surface of comet 67P/Churyumov–Gerasimenko

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, presents the varied and dramatic terrain of the mysterious rock. 

The images shows a raised plateau on the larger lobe of Comet 67P/ChuryumovñGerasimenko. 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

Incredibly, many of the images were taken at at less than six miles (10km) from the comet's surface, and reveal what a challenging task Philae has ahead of it. 

The Philae probe aims to analyse the comet in more detail. 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. Philae will be released from a distance of 14 miles (22.5km) from the centre of 67P.

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) 

Five questions that you may have had about Rosetta landing

Jose Pellon-Bailon, one of eight flight engineers responsible for Rosetta, explained his team will have to make a series of Go or No-Go decisions before the landing.

There are a number of things that could go wrong. 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, moving Philae off course.

Another concern is the strange duck-shape of the comet, that means Philae could crash on landing, damaging its instruments.

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 hour after 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. 

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 could also become too hot to operate as the comet travels towards the sun. Scientist say it will be able to withstand temperatures of 150°C. 

 If the green light is given, communication between Rosetta and mission control will 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.

'This would be a huge disappointment,' he says. 'Of course, the landing mission would be off, but also we wouldn't have learned why.' 

Space in Videos: Ambition the film

Located in the heart of Darmstadt, around 20 minutes from Frankfurt, Esa's mission control centre will be a hive of activity on November 12th 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

Rosetta spacecraft: Story of the comet-chaser

'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.' 

Zoom in on the image below to find out where Rosetta is at the moment 

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